Department of Applied Chemistry, Waseda University , Tokyo 169-8555, Japan.
ACS Appl Mater Interfaces. 2017 Mar 29;9(12):10692-10698. doi: 10.1021/acsami.7b00403. Epub 2017 Mar 20.
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 μS/cm at E and corresponded to a redox hopping mechanism. The apparent electron diffusion coefficient was 1.9 × 10 cm/s at room temperature, and at short times the ion diffusion was limiting with a diffusion coefficient of 6.5 × 10 cm/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 μm 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.
为了合理地设计新型、高效的有机活性电池材料，必须研究电荷输运的基本参数。在此，我们报告了 TEMPO 含氧化还原聚合物中的电子扩散的电子电导率，并且首次确定了 TEMPO 自交换在有机溶剂中的重组能。在 E 时，电子电导率为 8.5 μS/cm，对应于氧化还原跳跃机制。在室温下，表观电子扩散系数为 1.9×10 cm/s，在短时间内，离子扩散受到限制，扩散系数为 6.5×10 cm/s。重组能确定为 1.01 eV，表明 TEMPO 基团所处的化学环境相当具有极性。讨论了此类材料在有机储能中的应用。由于证明了通过 10 μm 的电导率，我们表明，如果能够确保足够的溶胀性，电荷可以在电池电极中通过几微米厚的层传输，而无需任何导电添加剂。
