The recent discovery that metal-free polyterthiophene (PTTh) prepared by iodine-vapor-assisted polymerization (IVP) can catalyze the hydrogen evolution reaction (HER) when illuminated, and this light-enhanced electrolysis expresses a non-Nernstian relation with pH, provides the foundation for further improvement of the photovoltage of the reaction by engineering the band structure of the light-absorbing polymer. Deviating from an all-thiophene backbone, using poly(1,4-di(2-thienyl))benzene (PDTB) lowers the highest occupied molecular orbital level by approximate to 0.3 eV compared with polythiophene, and PDTB simultaneously maintains the photoelectrocatalytic properties without an all-thiophene backbone, resulting in very high conversion rate of 600 mmol(H-2) h(-1) g(-1) at 0 V versus the reversible hydrogen electrode (RHE) at pH 11. PDTB shows the same non-Nernstian behavior as PTTh with increasing onset potential (versus RHE) at higher pH, and the open circuit potential on PDTB under visible light reaches 1.4 V versus RHE at pH 12. The PDTB photocathode thus produces a photovoltage above the theoretical potential for the complete water-splitting (1.229 V) and is indeed able to produce hydrogen in a one-photon-per-electron light-driven water splitting setup with MnOx as the anode at a rate of 6.4 mmol h(-1) g(PDTB)(-1).

We report the use of polyterthiophenes (PTTh) as a rare, combined light-harvester and catalyst for the hydrogen evolution reaction at high pH. Illuminated PTTh in combination with a MnOx anode in a two-electrode setup exhibited stable water-splitting at a bias-potential of only 0.3 V at pH 12. This confirms that PTTh used as photocathode can produce photovoltages of at least 900 mV for the hydrogen evolution reaction at high pH and is therefore a suitable match for traditional water-oxidation catalysts such as MnOx, CoOx, and RuOx. Films of PTTh were fabricated using a novel, metal-free method where iodine vapor is used as oxidant; thus, previously observed interference from metal residuals was omitted and thereby a gravimetric photo electrocatalytic conversion rate of 330 mmol(H-2) h(-1) g(-1) was achieved in phosphate buffer (pH 7) at 0 V vs. RHE. A striking property of this new strand of polythiophene was an "inverse" correlation (compared to that predicted using the Nernstian relationship) between the onset potential for the light-assisted water reduction reaction and pH: the potential (vs. RHE) required for a given current was more positive at higher pH, which is not observed for other (photo-) electrocatalytic materials, and indicates that the charge neutralization of PTTh (rather than the pH) guides the onset potential.

An ambient-light-promoted and,metal-free three-component reaction of active methylene compounds perfluoroalkyl iodides, and guanidines/amidines is reported: This constitutes a powerful method to prepare prfluoroalky-lated pyrinudines with mild reaction Conditions, broad substrate scope, excellent functional group tolerance, and simple operation. A radical/polar mechanism involving the formation of a halogen-bond adduct and radical cross-coupling is proposed.

To, design new and better organic active battery materials in a rational fashion, fundamental parameters of the charge transport must be studied. Herein we report on the electronic conductivity by electron diffusion in a TEMPO-containing redox polymer, and the reorganization energy of the TEMPO self exchange in an organic solvent is determined for the first time. The electronic conductivity was 8.5 mu S/cm at E-0 and corresponded to a redox hopping mechanism. The apparent electron diffusion coefficient was 1.9 x 10(-9) cm(2)/s at room temperature, and at short times the ion diffusion was limiting with a diffusion coefficient of 6.5 x 10(-10) cm(2)/s. The reorganization energy was determined to be 1.01 eV, indicating a rather polar chemical environment for the TEMPO groups. The implications for the usage of this type of materials in organic energy storage are discussed. As conductivity through 10 gm was demonstrated, we show that, if sufficient swellability can be ensured) charge can be transported through several micrometer thick layers in a battery electrode without any conducting additive.

Understanding the reaction distributions inside a polymer electrolyte fuel cell (PEFC) is essential for the higher performance and durability. We have developed a new see-through cell and visualized the distributions of oxygen partial pressure and current density inside a running PEFC at the temperature of 40 and 80 degrees C and the relative humidity of 53%. The oxygen utilization was changed from 0% to 80% by changing the current density. At higher oxygen utilizations, the current density was higher and therefore the water generation. Generated water droplets in the flow channel were also visualized, allowing for the simultaneous visualization of the distribution of the oxygen partial pressure, current density, and water droplets. By combining the observations of all three parameters, the reactions inside a membrane electrode assembly were discussed. (C) 2017 Elsevier B.V. All rights reserved.

5本ストレート流路をもつ固体高分子形燃料電池（PEFC）の、低温起動時のアノードガス拡散層（GDL）表面における酸素分圧可視化を行った。GDL表面には酸素感応色素を塗布した。PEFCの低温起動中に透明のエンドプレートを通してGDL表面に緑色光を照射し、色素からの赤色発光をCCDカメラで撮影した。得られた発光像をピクセルごとにコンピュータ処理し2次元の酸素分圧可視化像に変換した。初めは両端の流路でもっぱら発電が進行したが、発生水による触媒層凍結により、発電領域は中央流路に移動していくことが明瞭に観察された。

Strong interchain interactions render unsubstituted polythiophene un-fusible, non-melting, and insoluble. Therefore, control of the packing structure, which has a profound effect on the optical and electronic properties of the polymer, has never been achieved. Unsubstituted polythiophene was prepared in the one-dimensional channels of [La(1,3,5-benzenetrisbenzoate)](n), where polymer chains form unprecedented assembly structures mediated by the host framework. It is noteworthy that the emission and carrier transport properties were drastically changed by varying the number of chains within a particular assembly. The response of the composite to additional guests is also examined as a method to use the composites as low-concentration sensors. Our findings show that the encapsulation of polymer chains in host materials is a facile method for understanding the intrinsic properties of conjugated polymers, along with controlling and enhancing their functions.

Reversible addition-fragmentation chain transfer polymerization yields reactive block copolymers bearing the pentafluorophenyl ester (PFPA) group, and subsequent Click amidation using 2,2,6,6-tetramethylpiperidine-N-oxyl- and imidazolium-functionalized primary amines produces the corresponding functional block copolymers, leading to installation of statistical radical-and ionic sites into the PFPA segment. The monolayered thin film devices fabricated using the obtained block copolymers exhibit repeatable switching of electric conductivity (on/off ratio > 10(3)) under a bias voltage, which reveals that the coexistence of radicals and ions in the same spherical domain of the copolymer layer is a prerequisite for repeatable switching memory.

Visualization of the oxygen partial pressure (p(O(2))) was performed at the surface of a gas diffusion layer (GDL) and the upper part of the gas-flow channel of the cathode of an operating polymer electrolyte fuel cell (PEFC) with straight flow channels by using an oxygen-sensitive luminescent dye film. The gradient of p(O(2)) inside a channel was clearly observed, even on the GDL surface across the channel. A numerical simulation was performed to understand the reaction distributions inside the PEFC. By visualization and numerical simulation, the distributions of p(O(2)), the current density, water concentration, and temperature in the operating PEFC were obtained, and the relationships between the parameters were studied. Supersaturated water inside the cell was found both experimentally and computationally. p(O(2)) and the water concentration were concluded to be the two most important factors in determining the distribution of power generation.

Visualization of the oxygen partial pressure (p(O(2))) was performed at the surface of a gas diffusion layer (GDL) and the upper part of the gas-flow channel of the cathode of an operating polymer electrolyte fuel cell (PEFC) with straight flow channels by using an oxygen-sensitive luminescent dye film. The gradient of p(O(2)) inside a channel was clearly observed, even on the GDL surface across the channel. A numerical simulation was performed to understand the reaction distributions inside the PEFC. By visualization and numerical simulation, the distributions of p(O(2)), the current density, water concentration, and temperature in the operating PEFC were obtained, and the relationships between the parameters were studied. Supersaturated water inside the cell was found both experimentally and computationally. p(O(2)) and the water concentration were concluded to be the two most important factors in determining the distribution of power generation.

The integration of functional components such as metal nanoparticles, metal salts, or ionic liquids with well-defined block copolymer (BCP) nanotemplates via non-covalent bond interactions has afforded hybrid functional materials. Here, we designed an ionic liquid (IL)-functionalized redox-active TEMPO (2,2,6,6-tetramethylpiperidine-N-oxy) radical (guest), investigated phase-selective incorporation/placement into host BCP nanostructured matrices, and established a rational approach to functionalize BCP templates. On-demand domain functionalization of poly(styrene-b-ethyl-ene oxide) (PS-b-PEO) was triggered by ion-ionophore interaction, as verified by the suppression of PEO melting transition in DSC, and the swelling behavior of the PEO spherical domain in AFM, TEM, and X-ray scattering characterizations. The obtained BCP layer containing the redox-active TEMPO and IL was utilized as an active layer in the diode-structured memory device, which exhibited on/off resistive switching (on/off ratio >10(3)). Systematic placement of TEMPO and IL in the BCP spherical domain allowed for tuning of the switching characteristics and revealed that the formation of a discontinuous redox-active domain was critical for rewritable resistive switching.

The integration of functional components such as metal nanoparticles, metal salts, or ionic liquids with well-defined block copolymer (BCP) nanotemplates via non-covalent bond interactions has afforded hybrid functional materials. Here, we designed an ionic liquid (IL)-functionalized redox-active TEMPO (2,2,6,6-tetramethylpiperidine-N-oxy) radical (guest), investigated phase-selective incorporation/placement into host BCP nanostructured matrices, and established a rational approach to functionalize BCP templates. On-demand domain functionalization of poly(styrene-b-ethyl-ene oxide) (PS-b-PEO) was triggered by ion-ionophore interaction, as verified by the suppression of PEO melting transition in DSC, and the swelling behavior of the PEO spherical domain in AFM, TEM, and X-ray scattering characterizations. The obtained BCP layer containing the redox-active TEMPO and IL was utilized as an active layer in the diode-structured memory device, which exhibited on/off resistive switching (on/off ratio >10(3)). Systematic placement of TEMPO and IL in the BCP spherical domain allowed for tuning of the switching characteristics and revealed that the formation of a discontinuous redox-active domain was critical for rewritable resistive switching.

© The Royal Society of Chemistry 2015. The topochemical conversion of a dense, insulating metal-organic framework (MOF) into a semiconducting amorphous MOF is described. Treatment of single crystals of copper(i) chloride trithiocyanurate, CuICl(ttcH3) (ttcH3 = trithiocyanuric acid), 1, in aqueous ammonia solution yields monoliths of amorphous CuI1.8(ttc)0.6(ttcH3)0.4, 3. The treatment changes the transparent orange crystals of 1 into shiny black monoliths of 3 with retention of morphology, and moreover increases the electrical conductivity from insulating to semiconducting (conductivity of 3 ranges from 4.2 × 10-11 S cm-1 at 20 °C to 7.6 × 10-9 S cm-1 at 140°C; activation energy = 0.59 eV; optical band gap = 0.6 eV). The structure and properties of the amorphous conductor are fully characterized by AC impedance spectroscopy, X-ray photoelectron spectroscopy, X-ray pair distribution function analysis, infrared spectroscopy, diffuse reflectance spectroscopy, electron spin resonance spectroscopy, elemental analysis, thermogravimetric analysis, and theoretical calculations.

Visualization inside polymer electrolyte fuel cells (PEFCs) for elucidating the reaction distributions is expected to improve the performance, durability, and stability. An oxygen-sensitive film of a luminescent porphyrin was used to visualize the oxygen partial pressures in five straight gas-flow channels of a running PEFC with liquid-water blockages formed at the end of the channels. The blockage greatly lowered and unstabilized the cell voltage. The oxygen partial pressure decreased nearly to 0 kPa in the blocked channel. With a water blockage in a channel, the oxygen partial pressures in the adjacent channels were lowered due to an extra demand of oxygen consumption. When the number of the blocked channels increased, the oxygen partial pressure in the unblocked channels became much lowered. When the water blockages disappeared, the oxygen partial pressures quickly returned to the values before plugging. The influence of the cross flows of air through the gas diffusion layers in straight channels was much smaller than that in serpentine flow channels. (C) 2014 Elsevier B.V. All rights reserved.

Redox-active, phenothiazine-functionalized polymers were synthesized and employed as a promising cathode-active material (similar to 3.7 V vs. Li, 77 Ah kg(-1)) in a rechargeable battery. The longer spacer between phenothiazine and the polymer backbone contributed to the stability of the formed radical cations, resulting in decelerated self-discharge and improved cycle performance.

Visualization of the oxygen partial pressures was carried out at the surface of a gas diffusion layer (GDL) for the first time together with the upper part of the gas-flow channel of the cathode of a running polymer electrolyte fuel cell (PEFC) using two different oxygen-sensitive luminescent dye films. The visualized distributions of the oxygen partial pressures at the GDL and the upper gas-flow channel during the PEFC operation were very different in a conventional test cell. The change in the distribution of the oxygen partial pressures was observed by changing the oxygen utilization, which should be connected with the reactive locations in the membrane-electrode assembly (MEA). A numerical calculation was carried out to understand the distributions of water and current density inside the MEA. The water distribution inside the MEA was confirmed to strongly affect the distributions of the current density and the oxygen /partial pressure. (C) 2014 Elsevier B.V. All rights reserved.

Ring-opening metathesis polymerization (ROMP) using Grubbs third-generation catalyst directly yielded a norbornene-based polymer bearing robust redox-active radicals without any protection. Successive addition of imidazolium-containing norbomene in a one-pot reaction during ROMP produced pendant radical- and ion-containing block copolymers. The diode-structured thin-film devices fabricated with the obtained block polymers that had morphologies of spheres, lamellae, and inverse spheres exhibited conductive switching (write-once read-many-times, WORM) under a bias voltage, which revealed the dominant effect of the location of radicals and ions in the microphase-segregated domains on memory characteristics.

The fabrication of modern microelectronic silicon devices mechanically challenges these thin silicon substrates during manufacturing operations. Melt and solution polyesterification enabled the synthesis of polyesters containing photoreactive o-nitro benzyl ester units for use as a potential photocleavable adhesive. Melt transesterification provided a solvent-free method for synthesis of 2-nitro-p-xylylene glycol (NXG)-containing polyesters of controlled molecular weights. 1H NMR spectroscopy confirmed the chemical composition of the photoactive polyesters. Size exclusion chromatography (SEC) determined the number-average molecular weights (Mn) of the polyesters synthesized in the range of 6000 to 12000g/mol. 1H NMR spectroscopy confirmed increasing levels of photocleavage of the o-nitro benzyl ester functionality with increasing exposure to broad wavelength UV irradiation, and exposure levels ranged from 0187J/cm2 UVA. Photocleaveage of approximately 90% of the o-nitro benzyl ester (ONB) units within the backbone of the polymer occurred at maximum dosage. Wedge fracture testing revealed approximately a two-fold decrease in fracture energy upon UV irradiation, suggesting that these structural adhesives offer potential for commercial flip bonding applications.

Redox-active but highly durable nitroxide radicals, that is, 2,2,6,6-tetramethylpiperidinyl-4-oxy (TEMPO), enabled direct electrospinning of radical-containing polymers without additional processing aids (such as polymer blends, post-doping, or protection/deprotection) and produced redox-active fibrous membranes with high surface area. The solution rheological behavior of the TEMPO-substituted polymethacrylate was similar to the neutral conventional polymers, and electrospinning of the radical polymers yielded submicrometer-scaled fibrous membranes without any defects on the radical moiety. The obtained membrane exhibited stable redox response, leading to redox catalysts or electrode-active materials toward organic-based flexible rechargeable battery. Polymer Journal (2012) 44, 264-268; doi:10.1038/pj.2011.120; published online 7 December 2011

"Radical polymers" bearing a high density of unpaired electrons in a pendant, non-conjugated fashion on each repeating unit were utilized as cathode- and anode-active materials in a totally organic-based rechargeable battery. Careful molecular design of radical polymers such as nitroxide and galvinoxyl derivatives produced remarkably stable p- and n-type redox couples, which provided three different battery configurations. The power-rate performance of these cells was excellent (360 C rate, 10 sec charge/discharge), as a result of the rapid redox process of the organic radical moieties in the amorphous polymer layer. Organic polymer-based electrodes also allowed their utilization to a flexible, paper-like, and transparent rechargeable energy-storage device. © 2012 American Chemical Society.

Start-up and shut-down cycling in PECFs causes severe degradation, because the carbon supports at the cathode catalyst layers are corroded due to the instantaneous reaction with H2O. We developed a new CO2 visualization system using a CO2-sensitive dye for detecting the generation of CO2 during the corrosion processes in real time and with spatial resolution. The corrosion occurring during the shut-down process continued longer near the inlet and produced a more serious effect than during the start-up process, near the outlet. This new CO2 visualization technique should help to minimize the corrosion of carbon supports in all types of PEFCs. (C) 2012 The Electrochemical Society. [DOI:10.1149/2.018204esl] All rights reserved.

A TEMPO-substituted ionic liquid was selectively incorporated into well-defined, self-assembled block copolymer templates, which served as an active layer for organic nonvolatile memory. Phase structures (sphere, cylinder, and lamellae) and their orientation modulated the resistive switching behavior, which demonstrated the unprecedented, morphology-driven charge transport in the organic electronic devices.

Radical polymers bearing a high density of unpaired electrons in a pendant, non-conjugated fashion on each repeating unit provided a rapid, reversible, and quantitative redox behavior in an electrode form. Careful selection of radicals (TEMPO, galvinoxyl, and nitronylnitroxide, etc.) produced remarkably stable p- and n-type redox couples, which lead to the totally organic-based rechargeable batteries. The power-rate performance of these cells was excellent (360 C rate, 10 sec charge/discharge), as a result of the simple, rapid redox process of the organic radical moieties with no associated structural change in the amorphous polymer layer. Organic polymer-based electrodes are amenable to roll-to-roll or inkjet processing, which allowed the fabrication of a flexible, paper-like, and transparent rechargeable energy-storage device, which could be embedded in radio-frequency identification tags, smart cards and electronic paper.

The p- and n-type bipolar redox-active radical polymer with a nitronylnitroxyl group, poly(nitronylnitroxylstyrene), expands its utilization as a cathode-or anode-active material in organic polymer-based rechargeable devices with two unprecedented configurations: a poleless battery and a "rocking-chair type" battery. These batteries exhibit a remarkably high power rate capability (chargeable within 20 s) and high cycle performance.[GRAPHICS].

To maximize the theoretical redox capacity of polymers containing cyclic nitroxides as redox active pendant groups for high density charge storage application, a compact five membered ring with the smallest equivalent weight among the robust cyclic nitroxides was directly bound to a poly(ethylene oxide) chain 2,2,5,5 Tetramethyl 3 oxiranyl-3-pyrrolin 1 oxyl was synthesized and polymerized via anionic coordinated ring-opening polymerization utilizing diethyl zinc/H2O as an initiator The unpaired electron in the monomer survived during the polymerization giving rise to a high density redox polymer with a weight-specific theoretical capacity of 147 mA h/g Cyclic voltammetry of the polymer layer confined at the surface of an electrode revealed a large redox capacity comparable to the theoretical capacity which was ascribed to the efficient swelling and yet insoluble properties of the polyether in electrolyte solutions by virtue of the high molecular weight of >10(5) and adhesive properties allowing immobilization of the layer on the electrode surface The redox capacity also indicated that the ionophoric polyether matrix accommodated electrolyte anions through the polymer/electrolyte interface to neutralize positive charges produced by the oxidation of the neutral radicals at the polymer/electrode interface The diffusion coefficient for the redox gradient driven charge hopping process corresponded to a large second order rate constant in the order of 10(7) M-1 s(-1), which suggested an efficient electron self-exchange reaction throughout the polymer layer due to the large redox site population and hence to the small intersite distance Test cells fabricated with a polymer/carbon fiber composite layer on an aluminum current collector as the cathode and a Li anode sandwiching an electrolyte layer were capable of charging and discharging as a secondary battery with an output voltage near 3 7 V and were durable for more than 10(3) charging discharging cycles without substantial degradation

Polyimides and poly(siloxane imide)s containing photo-active cyclobutane diimide units were developed as reversible adhesives for temporary bonding in micro-fabrication processes. Poly(amic acid) formation in dipolar aprotic solvents and subsequent chemical or thermal solution imidization yielded the corresponding organic soluble polyimides. Incorporation of nonplanar (alicyclic or bicyclic) structures and poly(dimethyl siloxane) blocks into the main chain improved the solubility. The synthesized poly(siloxane imide)s afforded tough and ductile films, which exhibited a rubbery plateau in the storage modulus, as observed using dynamic mechanical analysis. This plateau was attributed to the microphase-separation of the poly(dimethyl siloxane) segments and the polyimide segments. Spin-coated thin films on silicon substrates were photo-degraded with ultraviolet-C (UVC) light (254nm). Nuclear magnetic resonance (NMR) spectroscopy demonstrated a growth in the proton resonance corresponding to the formation of maleimide functionality upon photo-cleavage. This observed photo-cleavage suggests possible applications as temporary structural adhesives.

Two redox-active poly(oxoammonium salt)s were synthesized via chemical oxidation of a TEMPO-substituted polymer, or conventional radical polymerization of the oxoammonium monomer, respectively. The diode-structured thin film device composed of poly(oxoammonium salt) with radical conc. of 6-43% exhibited a resistive switching behavior (ON-OFF ratio > 10(3)), in contrast to the radical-free poly(oxoammonium salt), which revealed that the coexistence of radical/oxoammonium salts contributed to a significant change in I-V characteristics.

A n-type and redox-active radical polymer bearing galvinoxyl radicals, poly (galvinoxylstyrene), is utilized as an anode-active material, which enabled, for the first time, the fabrication of a totally organic polymer-based rechargeable battery in conjunction with p-type redox-active radical polymer. This battery was characterized by its remarkably high power rate capability.

A series of poly(arylene ether sulfone) copolymers containing the diazocine unit (0, 20, 50, 80, 100 mol %) were synthesized via step-growth polymerization. Copolymer compositions exhibited number-average molecular weights exceeding 30 000 g/mol, and mechanically ductile films were obtained for all compositions. The random copolymers exhibited enhanced thermal stability (T-d10% = 500-550 degrees C) and mechanical properties (tensile stress = 45-65 MPa), and the thermomechanical performance was predictable based on copolymer composition. A secondary transition in the dynamic mechanical analysis appeared at 28 degrees C, which was attributed to segmental motion of the bulky diazocine and biphenyl units. X-ray single crystallography and H-1 NMR spectroscopy as a function of temperature revealed that the diazocine ring existed in the boat-shaped conformation. The effective dipolar couplings of site-specific H-1-C-13 dipolar couplings in the aromatic rings were measured using DIPSHIFT solid state NMR spectroscopy at various temperatures. The experimental data indicated that the bulkier diazocine group experienced slower ring-flip motion than the smaller phenylene group. Cyclic voltammograms of diazocine-containing poly(arylene ether sulfone)s exhibited two reversible reduction peaks at -0.68 and -1.21 V under inert and basic conditions. UV spectra of the diazocine group in the reduced state indicated an extended pi-electron structure, which supported the boat- to planar-conformational change (molecular actuation) via redox reactions.

Reversible adhesion has long been of significant practical interest for a range of applications including controllable adhesion, photolithography, temporary bonding required for wound dressings and certain manufacturing processes, and disassembly for repairing and recycling. UV degradable materials find applications in medical and microelectronic fields due to their dramatic property changes after UV irradiation, allow for easy removal of the adhesive. A series of UV cleavable adhesives has been synthesized to investigate their ability to debond more readily as a function of UV radiation dosage. In this paper a wedge test, from elevated temperature exposure or photo-degradation, is used to measure the reduction in resistance to debonding. By using fracture mechanics principles and recording the growing debond length as a function of exposure, the fracture energy can be determined. Tests are conducted to measure how fracture energy decreases after varying amounts of thermal exposure or UV irradiation. The debond surfaces and locus of failure are also investigated in this study.

Robust but redox-active radical polymers bearing 2,2,6,6-tetramethylpiperidin-N-oxy (TEMPO) were investigated as a metal-free, green mediator/catalyst for the oxidation of alcohol derivatives, and as a new electrode-active and charge-storage material. The TEMPO-mediated oxidation of the primary alcohol group of the natural cellulose improved the water-dispersivity of cellulose, and the polymer-supported catalysts or redox resins allow facile removal of catalysts from products by simple filtration. Other radical molecule (e.g. galvinoxyl) was also used as a mediator, which is coupled with the molecular oxygen. A reversible one-electron redox reaction of TEMPO allowed its application as an electrode-active material featuring high cyclability (> 500 cycles), relatively high battery electrode capacity (100-135 mAh/g), and fast electrode kinetics, leading to the high power rate capability of the battery. The radical polymer-based electrodes also provided good processability and shape flexibility, which promised the paper-like and wearable energy-storage devices.

In search of polymer backbones to bind organic radical pendant groups as redox centers for high-density charge storage application, polyether was employed as a flexible chain with a low glass transition temperature and affinity to electrolyte solutions. Cyclic ethers bearing nitroxide radicals were synthesized and polymerized via ring-opening polymerization utilizing various initiators. Polyethers bearing robust radical substituents such as 2,2,6,6-tetramethylpiperidin-l-oxyl-4-yl and 2,2,5,5-tetramethyl-2,5-dihydro-1H-pyrrol-l-oxyl-3-yl groups with high density, i.e., per repeating unit with small equivalent weights, were prepared by the anionic polymerization of the corresponding epoxides. Cyclic voltammetry of the radical polyethers, obtained for polymer/carbon composites confined at an aluminum current collector, revealed large redox capacities comparable to the formula weight-based theoretical values, which was ascribed to the efficient swelling and yet insoluble properties of the polyethers in electrolyte solutions by virtue of their high molecular weights and adhesive properties to be held on electrode surfaces. The redox capacity also indicated that the ionophoric polyether matrix accommodated electrolyte anions to compensate positive charges produced by the oxidation of the neutral radicals at the polymer/electrode interface, allowing charge propagation deep into the polymer layer by a site-hopping mechanism. Test cells fabricated with the polymer/carbon composite as the cathode and a Li anode, sandwiching an electrolyte layer, performed as a secondary battery at output voltages near 3.6 V without substantial degradation even after 100 charging-discharging cycles.

A nitroxide radical functional polymer was photocrosslinked for the first time without significant side reactions, producing a cathode-active thin film, leading to an organic-based paper battery.

A nitroxide radical is electrochemically oxidized to the oxoammonium cation(p-type doping) and reduced to the nitroxide reversively. Based on this redox property, we have reported application of the nitroxide radical polymer to an electrode-active material. Epoxide derivatives bearing 2,2,6,6- tetramethylpipelidine-A/-oxyl were synthesized and polymerized by ring-opening polymerization. In this report, the obtained polymers were characterized by IR, elemental analysis, ESR and SQUID measurement. Redox property of these radical polymers was examined by cyclic voltammetry. The cycle performance during charging and discharging of the fabricated cell displayed a plateau voltage at 3.7 V, and no significant deterioration in the capacity was observed more than 100 cycles.

Galvinoxyl radical, known as a stable organic radical, was selected as a new candidate for a cathodeand/or anode-active material for a secondary battery. Styrene derivative bearing the galvinoxyl radical was synthesized via four steps, and polymerized to give the precursor polymer (Mn=10 4). Chemical oxidation yielded the corresponding radical polymer. The obtained polymer was characterized by spectroscopic measurements. Electrochemical measurements revealed its stable redox behavior. The cell performance will also be reported.

Based on the redox couples of a nitroxide radical, organic radical polymers have been utilized as the electrode-active or charge-storage component for a secondary battery, so-called "organic radical battery". Organic radical battery has several advantages: high capacity, high power-rate performance, long cycle ability, and environmentally-benign features. We report here the synthesis of a series of radical polymers and their redox properties. TEMPO-substituted polyether displayed its improved compatibility with the electrolyte solution. Photo-crosslinking of TEMPO-substituted polynorbornene was investigated as a facile and useful method leading to a slim and flexible battery. Poly (galvinoxystyrene) displayed a stable n-type redox behavior at 3.2 V vs. Li/Li+, which also holds considerable potential as an anode-active material, leading to purely organic-derived batteries. The cell performance will be also reported.

Diphenylnitroxide derivatives are known to their high radical stability and stable redox properties suitable as an electrode-active material of the next generation secondary battery. A series of p, p'-disubstituted diphenylnitroxide derivatives were synthesized, and p-substituent effect on their redox properties were investigated by electrochemical measurements. Styrene derivative bearing the diphenylnitroxide radical was synthesized via 4 steps, and polymerized to give the precursor polymer (Mn =3.2 × 103). Chemical oxidation of this polymer yielded the corresponding radical polymer. Its redox behavior will be also reported.

Poly(TEMPO-substituted norbornene) was synthesized by ring-opening metathesis polymerization by using Grubbs catalyst. The polymer was photo-crosslinked by bisazide or oxetane derivatives, and applied to an electrode-active material. The obtained radical thin film displayed a stable redox behavior at 3.6V vs. Li/Li+.The test cell was fabricated with the polymer cathode and lithium anode.No deterioration of the capacity was observed after 500 cycles.

Nitroxide-substituted polyether was synthesized as a cathode-active material for a secondary battery. Anionic ring-opening polymerization of a TEMPO-bearing glycidyl ether was carried out under bulk conditions to yield the corresponding polymer with the molecular weight of >104. The obtained polymer was insoluble, but slightly swollen in the electrolyte solution (ethylene carbonate/propylene carbonate). The test cell fabricated with a carbon composite cathode of this radical polymer displayed a plateau voltage at 3.5 V vs. Li/Li+. The cell performance was maintained even with a higher amount of the radical polymer loaded in the composite electrode, which could be ascribed to the flexible and rubbery polyether backbone and its higher compatibility with the electrolyte solution. Copyright © 2006 WILEY-VCH Verlag GmbH & Co. KGaA.

The charging and discharging mechanism of a prototype organic radical-based lithium-ion battery, where the p-type nitroxide radical polymer forms a cathode operated in conjunction with a carbon anode, are discussed. During the charging process, the p-type radical polymer in the cathode is oxidized to the oxoammonium form. During the discharging process, the nitroxide radical is regenerated by reduction of the oxoammonium. The organic radical polymer has solvent solubility and processability, which facilitates battery manufacture through a wet, printable, and rollable process.

A nitroxide radical is able to be electrochemically oxidized to the corresponding oxoammonium cation (p-type doping) and reduced to the aminoxyl anion (n-type doping). These redox properties are suitable as an electrode-active material of a next generation secondary battery. We have reported an application of TEMPO-substituted polymethacrylate to an cathode material. We report here synthesis of two nitroxide-substituted polystyrene derivatives and their electrochemical properties. Cyclic voltammogramsoftheradicalpolymersshowedthep- or n-type reversible waves which are tunable by molecular designing. TEMPO-substituted polynorbomene was synthesized by ring-opening metathesis polymerization. The solubility and processability of the radical polymer was tuned by cross-linking. The electron transfer process in the polymer composite electrode was examined by CV, normal pulse voltammmetry, and impedance measurement. The cell performance was also investigated.

Nitroxide radical electrochemically can be oxidized to oxoammonium cation(p-type doping) and reduced reversively. Based on these redox properties, we have reported the application of nitroxide radical to an electrode-active material. In this report, we synthesized polyethyleneoxide derivatives bearing 2,2,5,5-tetramethylpirrolidine-N-oxyl(proxyl radical) and studied their redox properties. 2,2,5-trimethyl-5-oxiranylmethylpyrrolidin-1-yloxy was synthesized from 2-nitropropane via four step reactions. The obtained proxyl-substituted epoxide was polymerized by ring-opening polymerization. Poly(proxyl radical)s were identified by IR, ESR, SQUID measurement, and elemental analysis. Redox properties of these polyradicals were examined by cyclic voltammetry. The formal potential was 0.75V.

A nitroxide radical is stable at ambient conditions and has two redox couples; nitroxide radical is oxidized to oxoammonium cation (p-type doping) and reduced to aminoxyl anion (n-type doping). Based on these electrochemical properties, the nitroxide radical is expected as an electrode active material of secondary battery. In this report, we synthesized new polyacetylene derivatives bearing 2,2,5,5-tetramethylpyrrolidine-N-oxyl(proxyl radical) and studied their electrochemical properties. Two monomers were synthesized by Grignard reaction (from nitrone). The obtained acetylene monomer was polymerized by coordination polymerization and oxidized to its radical derivative. Poly(proxyl radical)s were identified by IR, ESR, SQUID measurement, and elemental analysis. Redox property of these poly(proxyl radical)s was examined by cyclic voltammetry.

The nitroxide radical is expected as an electrode active material of secondary battery. We synthesized polystyrene derivatives bearing nitroxide radical and investigated their electrochemical properties. Styrene monomer was synthesized from 5-bromo-2-aminobenzotrifluoride via four step reactions. The obtained styrene monomer was polymerized by radical polymerization and oxidized to its radical derivative. Electrochemical property of the radical polymer was examined by cyclic voltammetry. The formal potential was -0.76 V.

Purely organic-derived nitroxide radicals, including their polymer derivative, poly(2,2,6,6-tetramethylpiperidinyloxy methacrylate) (PTMA), were characterized as a new class of cathode-active materials for lithium batteries. PTMA was stable at ambient conditions, had a tunable solubility and processability, and could undergo thermal runaway without any odor and ash. The nitroxide radicals displayed a reversible and very rapid redox to form their oxoammonium salts, which enabled a high power-rate performance during the charge and discharge process of the battery. © 2004 Elsevier Ltd. All rights reserved.

The electron-transfer rate constants of nitroxide derivatives, 4-(N-t-butyl-N-oxylamino)-t-butylbenzene, 4-(N-t-butyl-N-oxylamino) methoxybenzene, and 2,2,6,6-tetramethylpiperidinyl-N-oxyl, were investigated by electrochemical methods, which demonstrated that these radicals can potentially be used as a high power-rate electrode-active material due to their fast electron-transfer process.

簡便かつ迅速なUV硬化反応に敢えて「光駆動型」の精密ラジカル重合機構を組み込むことで、時間軸を制御し、硬化膜の表面ナノ凹凸形状の付与、および内部にブロック共重合体のミクロ相分離に代表されるナノ構造を同時(その場)形成することで新たな機能性コーティングとしての展開を目的とした。有機触媒存在下で光照射により可逆的に解離し、重合を開始・制御できるC-I末端を持つ高分子ドーマントを合成・単離、UV硬化に適用することで、透明な硬化膜を与えるとともに内部にユニークな共連続傾斜ミクロ相分離構造を同時形成できることを明らかにした。各種光学フィルム、コーティング、多孔分離膜など幅広い展開が期待できる。

安定有機ラジカルのSOMO(Singly Occupied Molecular Orbital)上の電子交換反応に基づく局在型電荷授受と、π共役(HOMO-LUMO)のドープに基づく非局在型電荷伝播を組み込んだ有機蓄電材料の創出を目的とした。気相(酸化)重合法に着眼し、予めラジカル(反応活性種)を酸化剤で不活化することで重合阻害なく導電性高分子(例えばPEDOT)をその場(in-situ)形成、得られたラジカルポリマー／π共役系機能材料を電極としたウェラブルな全有機二次電池へと展開した。また気相重合を拡張し有機半導体のその場形成法としても提示した。

本課題では、予め化学酸化剤(例えばFe(OTs)3)を塗布し、共役モノマー(例えばEDOTなど)の蒸気を供給することで、導電性高いπ共役高分子を簡便に形成できる「気相酸化重合法」を起点に、従来とは逆の着想で「共役モノマーを予め塗布、揮発性の酸化剤を気相供給する」ことで、従来揮発性や熱安定性に制限されていた多様な共役モノマーの高分子化法として提示することを目的としている。特に各種元素(Se, Bなど)含有共役モノマーへと対象を拡張し、気相重合を「無置換・元素ブロック共役高分子」のその場形成法として展開した。
(1) 元素ブロック共役高分子の電子・光物性
昨年度までに気相重合で得たビセレノフェンやBODIPYなどの元素ブロック含有共役高分子を対象に、高分子ドナーとしての電子・光物性を検討した。ベンゾチアジアゾールなど電子求引性のコア部位導入やSe, Teなど重原子効果で長波長域の吸収を向上し、バンドギャップの調節を明らかにした。また、単層素子およびくし形電極を用いてホール移動度の異方性についても2桁程度あることを明らかにした。PCBMをアクセプターとして組み合わせた有機薄膜太陽電池では光電変換効率1%に留まり、界面制御が今後の課題として挙げられる。
(2) 電解重合との比較
気相重合及び電解重合で得られたポリチオフェンを例に、UV, AFMにより比較したところ、気相重合では100-200nmの粒状のポリチオフェンが緻密に形成され、より高い移動度を示すことを明らかにした。現在MOFを鋳型とする気相重合ポリチオフェンの異方導電性についても班内連携(A02班 京大植村グループ)と進めている。

有機ラジカルの迅速かつ安定な「電荷授受」能と、イオン液体の「電荷補償」能に着眼し、(a)精密重合によるブロック共重合体の合成、および(b)イオン液体をキャリアとした機能分子の自己集積化、の2つの手法でミクロ相分離した高分子薄膜に機能部位を精密に配置、組み込むことに成功した。特にミクロ相分離構造(モルフォロジー、配向性)、ラジカル／イオン部位の配置とメモリ特性(一回or繰り返し書込み可)との相関を明らかにするとともに、On/Offスイッチングの発現機構を探るべく、走査プローブ顕微鏡を用いた局所的な印加電圧による表面電位およびI-V特性変化からドメイン内の電荷注入・輸送過程について描像した

配向性高い共役高分子をその場(in-situ)形成できる「気相酸化重合」に着目し、各種元素(Si, Seなど)を含む低バンドギャップ・移動度高い高分子半導体の新しい形成法としての確立を目的とする。本年度は、従来とは逆の着想で「共役モノマーを予め塗布、揮発性の酸化剤を気相供給する」ことで揮発性や熱安定性に制限されていた多様な共役モノマー、特に各種元素(Se, Siなど)含有共役モノマーへ対象を拡げ、気相重合を適用するとともに、ドナー／アクセプター混合型光電変換層に向けた配向性高い高分子半導体の新しい形成法として提示した。
(1) 気相酸化剤を用いたオリゴチオフェンの気相酸化重合
ターチオフェン溶液を基板上に予め成膜後、化学酸化剤としてNOPF6またはI2蒸気雰囲気下で気相重合した。エタノールによる洗浄、ヒドラジンによる脱ドープを経て、無置換ポリチオフェンを各種有機溶媒に不溶な赤色薄膜として得た。I2を酸化剤とした場合、UV-vis-NIRスペクトルでは長波長側に光吸収の肩ピークが現れ、共役長の伸長および高い秩序性が示唆された。XPSスペクトルでは、I由来のピークがエタノール洗浄により消失し、NOPF6より酸化剤の除去が容易であった。
(2) 元素ブロック共役モノマーの拡張と気相重合
元素ブロック含有モノマーとして、セレノフェンおよびBODIPY誘導体を選択した。セレノフェンは酸化電位が高いため、ビセレノフェンへと誘導し、BODIPY誘導体では末端にチオフェンを導入して気相酸化重合に供した。気相重合により得られた共役高分子のMALDI-TOF MSより、分子量3000, 重合度10-20のピークを検出し、各モノマーの繰り返しと一致したことから、副反応なく重合体を与えることを明らかにした。また、気相重合により得られた薄膜は溶液重合よりも1桁高いホール移動度を示した。

有機ラジカルの迅速かつ安定な「電荷授受」能と、イオン液体の「電荷補償」能に着眼し、(a)精密重合によるブロック共重合体の合成、および(b)イオン液体をキャリアとした機能分子の自己集積化、の2つの手法でミクロ相分離した高分子薄膜に機能部位を精密に配置、組み込むことに成功した。特にミクロ相分離構造(モルフォロジー、配向性)、ラジカル／イオン部位の配置とメモリ特性(一回or繰り返し書込み可)との相関を明らかにするとともに、On/Offスイッチングの発現機構を探るべく、走査プローブ顕微鏡を用いた局所的な印加電圧による表面電位およびI-V特性変化からドメイン内の電荷注入・輸送過程について描像した。

有機ラジカルポリマーを電極活物質とした「有機ラジカル電池」のプロトタイプについて、軽量かつ成型性に優れる有機材料の特徴に基づく高いエネルギー密度と、ラジカル種の高速電子移動に由来するパワー密度をあわせもつ類例のない電池特性の予備的実証を起点に、有機ラジカル種の電子移動とそれにともなう電荷輸送特性の解明に基づく革新的有機電極材料の創出と、SOMO(半占有分子軌道)経由の有機電子移動に関する基礎化学開拓を目的とした。有機ラジカル種の基礎化学に立脚した合理的分子設計により、エネルギー密度と出力パワーを向上させ、安全・環境適合の次世代二次電池も提示した。

有機ラジカルポリマーを電極活物質とした「有機ラジカル電池」のプロトタイプについて、軽量かつ成型性に優れる有機材料の特徴に基づく高いエネルギー密度と、ラジカル種の高速電子移動に由来するパワー密度をあわせもつ類例のない電池特性の予備的実証を起点に、有機ラジカル種の電子移動とそれにともなう電荷輸送特性の解明に基づく革新的有機電極材料の創出と、SOMO(半占有分子軌道)経由の有機電子移動に関する基礎化学開拓を目的とした。有機ラジカル種の基礎化学に立脚した合理的分子設計により、エネルギー密度と出力パワーを向上させ、安全・環境適合の次世代二次電池も提示した。

安定かつ迅速な電荷授受能を有するラジカルと電荷補償能を果たすイオン対を、(1)TEMPO/イオン置換ブロック共重合体、(2)汎用ブロック共重合体へのTEMPO-イオン液体の選択的集積化、の2つの手法でミクロ相分離ドメインに精密に組み込み、相分離構造(スフィア、シリンダーなど)、およびその配向性により有機薄膜素子でのメモリ特性の発現、調節の創り分けが可能であることを明らかにした。

安定かつ迅速な電荷授受能を有するラジカルと電荷補償能を果たすイオン対を、(1)TEMPO/イオン置換ブロック共重合体、(2)汎用ブロック共重合体へのTEMPO-イオン液体の選択的集積化、の2つの手法でミクロ相分離ドメインに精密に組み込み、相分離構造(スフィア、シリンダーなど)、およびその配向性により有機薄膜素子でのメモリ特性の発現、調節の創り分けが可能であることを明らかにした

安定かつ迅速な電荷授受能を有するラジカルと電荷補償能を果たすイオン対を、(1)TEMPO/イオン置換ブロック共重合体、(2)汎用ブロック共重合体へのTEMPO-イオン液体の選択的集積化、の2つの手法でミクロ相分離ドメインに精密に組み込み、相分離構造(スフィア、シリンダーなど)、およびその配向性により有機薄膜素子でのメモリ特性の発現、調節の創り分けが可能であることを明らかにした。

(1)主鎖分子設計と酸化還元能ニトロキシド(TEMPO)を側鎖ラジカル種、ポリエーテル骨格を主鎖とする高分子は、電解液に不溶ながら適度に膨潤し、ガラス転移温度7gは室温以下と低く、TEMPO置換ポリメタクリレートに比べ柔軟であった。炭素繊維集電体への密着性、相容性の向上により、ラジカル含有量の高い複合電極でも容量高い充放電挙動(80Ah/kg)を示した。また主鎖にポリノルボルネンを選択したラジカルポリマーでは、光架橋の導入によりレドックス薄膜が容易に作成でき、成形性を付与した新しい電極活物質として、薄型かつ柔軟な有機ペーパー電池につながることを示した。
(2)ラジカル高分子膜での電子・物質移動過程の解析と電極作製の最適化TEMPO置換ポリノルボルネンを光架橋し得られる高分子薄膜のサイクリックボルタモグラムは、膜厚約250nmまでピーク電位幅の狭い表面吸着に由来する挙動を示し、迅速かつ定量的な電子移動過程を支持した。また、炭素との複合電極の走査電顕像より炭素繊維の周り約100nm厚みで高分子が覆う形態が観察され、高分子層内をホッピングして電子伝達されることが示唆された。
(3)n型ラジカルポリマーの合成と全有機電池への展開ポリ(ニトロキシルスチレン)では、置換基の電子効果によりレドックス対(p, n型)の選択および酸化還元電位の調節が可能であることをはじめて明らかにした。一方、酸化還元電位の異なる、例えばn型酸化還元能を有するポリ(ガルビノキシルスチレン)を負極、TEMPO置換ポリマーを正極として試作したセルでは、酸化還元電位差に対応する0.7Vに繰り返し安定な電位平坦部を示し、全有機から成る電池の動作をはじめて実証した。
以上とりまとめ、酸化還元ラジカル高分子の分子設計・合成と特性、特に次世代のエネルギー貯蔵材料の新たな道筋を示した。

(1)主鎖分子設計と酸化還元能ニトロキシド(TEMPO)を側鎖ラジカル種、ポリエーテル骨格を主鎖とする高分子は、電解液に不溶ながら適度に膨潤し、ガラス転移温度7gは室温以下と低く、TEMPO置換ポリメタクリレートに比べ柔軟であった。炭素繊維集電体への密着性、相容性の向上により、ラジカル含有量の高い複合電極でも容量高い充放電挙動(80Ah/kg)を示した。また主鎖にポリノルボルネンを選択したラジカルポリマーでは、光架橋の導入によりレドックス薄膜が容易に作成でき、成形性を付与した新しい電極活物質として、薄型かつ柔軟な有機ペーパー電池につながることを示した。
(2)ラジカル高分子膜での電子・物質移動過程の解析と電極作製の最適化TEMPO置換ポリノルボルネンを光架橋し得られる高分子薄膜のサイクリックボルタモグラムは、膜厚約250nmまでピーク電位幅の狭い表面吸着に由来する挙動を示し、迅速かつ定量的な電子移動過程を支持した。また、炭素との複合電極の走査電顕像より炭素繊維の周り約100nm厚みで高分子が覆う形態が観察され、高分子層内をホッピングして電子伝達されることが示唆された。
(3)n型ラジカルポリマーの合成と全有機電池への展開ポリ(ニトロキシルスチレン)では、置換基の電子効果によりレドックス対(p, n型)の選択および酸化還元電位の調節が可能であることをはじめて明らかにした。一方、酸化還元電位の異なる、例えばn型酸化還元能を有するポリ(ガルビノキシルスチレン)を負極、TEMPO置換ポリマーを正極として試作したセルでは、酸化還元電位差に対応する0.7Vに繰り返し安定な電位平坦部を示し、全有機から成る電池の動作をはじめて実証した。
以上とりまとめ、酸化還元ラジカル高分子の分子設計・合成と特性、特に次世代のエネルギー貯蔵材料の新たな道筋を示した。

　電荷蓄積能を持つp, n型レドックスポリマー存在下で、その場(in-situ)重合により導電性高分子(PEDOT, PEDOP)を形成することで、高容量かつフレキシブルな有機複合電極の創出を目的とする。本研究ではin-situ重合法として気相酸化重合および電解酸化重合を比較しながら、得られた複合層の電荷蓄積・輸送能について考察した。また、その場重合を有機半導体(ドナー材料)の調製法として提案し、アクセプターとの複合化による光電変換層の構築も試みた。1) p, n型ラジカルポリマーとの複合化とフレキシブル全有機二次電池の作製　気相酸化重合はラジカル機構で進行するため、TEMPO存在下では重合阻害される。過剰量の酸化剤p-トルエンスルホン酸鉄(III) (Fe(OTs)3)で予めTEMPOをオキソアンモニウムカチオンへと誘導後、基材(ガラス基板、PET不織布など)に成膜、EDOT雰囲気下で気相重合した(70°C, 60 min.)。電解酸化重合では、TEMPOが酸化される1.5 V vs. Ag/AgClを定電位印加し、その上でEDOTを供給、重合させることで複合膜を得た。得られたPEDOT/PTAm(1/3 w/w)複合膜の放電曲線では、120 C rate(30秒での高速充電に対応)においても理論容量を維持した。PEDOT組成の増加にともない出力特性が向上し、交流インピーダンス測定からも電荷移動抵抗の減少が見られたことから、PEDOTを介した電荷輸送の促進が支持された。　PET不織布上に形成したPEDOT/PTAm, PEDOT/PGSt複合膜をそれぞれ正・負極として、電解液としてイオン液体1-ブチル-3-メチルイミダゾリウムテトラフルオロボラート(BmimBF4)を含むセパレーターを挟み、ラミネートしてフレキシブルな全有機電池を作製した。両レドックスポリマーの酸化還元電位差に相当する0.67 Vにプラトー電位を示し、繰り返し安定な充放電挙動を示す二次電池として作動することを明らかにした。2) 気相重合を用いたドナー層の構築と光電変換素子の作製　ITO基板上にホール輸送層としてPEDOT/PSS水分散液を成膜後、酸化剤溶液(Fe(OTs)3/BuOH(1, 7, 10 wt%))を塗布しターチオフェンを気相重合した。エタノール洗浄、ヒドラジンによる脱ドープを経て、ドナー層として無置換ポリチオフェンを得た。アクセプター層としてPCBM/モノクロロベンゼン溶液を積層後、ホールブロッキング層としてTiOxを形成、Alを真空蒸着して積層型素子を作製した。また、PCBMと酸化剤を塗布し、気相重合させることによってドナー・アクセプター混合(BHJ)型素子も合わせて作製した。各層の膜厚最適化およびアクセプターとして吸光度、溶解性の高いPC71BMを用いることで、積層型素子の1 Sun照射下におけるJ-V測定より変換効率η = 0.63 %を示した。また、無置換ポリチオフェンから低バンドギャップ性のポリベンゾチアジアゾールへの拡張を試み、新たなドナー層構築法としての気相重合の可能性を見出した。　以上の成果を元に、新学術領域研究(元素ブロック)に申請し、無事採択された(2013.4.)。

(1) 光架橋ラジカルポリマーの合成と薄型二次電池への応用　電極としての成形性を付与させるため、TEMPO置換ポリノルボルネンを合成、光架橋を適用した。ノルボルネンジカルボン酸無水物を出発物として4-ヒドロキシ-TEMPOを反応させジエステルへ誘導、Grubbs触媒を用いて開環メタセシス重合し、高分子量体(分子量約2万)を得た。得られた高分子はTHF、クロロホルムなど有機溶媒に可溶で、高い成膜性を有した。ポリノルボルネンの主鎖オレフィン部位へ選択的にビスアジド誘導体を光付加させ、ラジカル部位の損傷なく架橋ラジカル薄膜を得た。ラジカル薄膜はアノード側約0.8 V対Ag/AgClにTEMPOのp型酸化還元対に由来する安定な酸化還元波を示し、膜厚250 nmまで導電補助剤なしでも迅速かつ定量的な電子授受が可能であることを明らかにした。光パターニングにより膜厚、形状を制御したラジカル薄膜が得られ、薄型かつ柔軟なペーパー電池につながることを実証した。(2) n型ラジカルポリマーの合成と全有機二次電池への展開　　n型の酸化還元能を有するガルビノキシルラジカルに着目し、負極活物質として全有機二次電池へ適用した。シリル保護したブロモフェノール誘導体をリチオ化、4-ブロモ-1-メチルベンゾエートと反応させガルビノキシ骨格を構築した。Stilleカップリングによりスチレンモノマーへと誘導し、二官能性アクリレートとラジカル共重合させることにより架橋、化学酸化を経てポリ(ガルビノキシルスチレン)を得た。塩基性下、0.1 V (対Ag/AgCl)にn型の酸化還元波を示し、TEMPO置換ポリノルボルネン正極と組み合わせ試作した電池では、それぞれの酸化還元電位の差に対応する0.7 Vに電位平坦部が現れ、両極とも有機ラジカルから成る二次電池の動作をはじめて実証できた。

1. n型ラジカルポリマーの合成と酸化還元挙動　ニトロキシドのo-位に電子吸引基としてトリフルオロメチル基を置換したスチレン誘導体を合成し、ラジカル重合、脱保護・化学酸化を経てラジカルポリマーへ誘導した。CVよりカソード側-0.76 Vにn型の酸化還元波が現れ、繰り返し掃引しても安定であった。無置換誘導体ではp型レドックスを示すことより、置換基の電子効果によりレドックス対の選択が可能であることを実証した。n型高分子で作製した炭素複合電極は、溶液と異なり不可逆な酸化還元挙動を示した。定電位電解、電解ESR、電解UV測定より安定性を検証中である。2. ラジカル高分子層における電子・物質(対イオン)移動過程の解析　　TEMPO置換ポリメタクリレートから成る高分子被覆電極(膜厚2x10-6m)のCVは、ピーク電位幅狭く、電気化学パルス法から高分子膜中における電荷の見かけの拡散係数Dappは10-8 (cm2/s)桁と見積もられ、高分子膜内においても速い電子移動を明らかにした。複合電極の走査電顕像より炭素繊維の周り約100 nm厚みで高分子が覆う形態が観察され、高分子層内をホッピングして電子伝達されていることが示唆された。3. TEMPO置換ポリグリシジルエーテルの合成と電気化学特性　高容量かつ電解質との相容性が期待できるポリエーテルを主鎖に選択、TEMPOを側鎖に置換したラジカルポリマーを分子設計、アニオン開環重合により分子量約3万の高分子量体を得た。ラジカルポリマー/炭素複合電極を正極、リチウム負極とした試作セルは、3.7 Vにプラトー電位、100サイクル後も安定した充放電挙動を示し、電極活物質としてきわめて安定であることを明らかにした。　今後は、選ばれたラジカルポリマーの電極・セル評価を進めるとともに、n型レドックス能を有するラジカルポリマーを分子設計・精密合成し、全有機から成る薄型フレキシブルな電池実現を目指し展開予定である。