In this study, we fabricated silk protein-derived carbon fabrics (SCFs) as electrodes for vanadium redox flow batteries (VRFBs) using a commercial silk fabric through a facile pyrolysis process, without any post-treatment. After the pyrolysis, the intrinsic fabric morphologies of the SCFs were maintained, resulting in highly macroporous structures. In addition, even after pyrolysis at high temperature above 1,600 °C, the SCFs contain sufficient heteroatoms such as oxygen and nitrogen on their surface, originated from their protein nature. As a result, SCF electrodes prepared by heating at 1,600 °C exhibited peak potential separation (ΔE_p) values as low as ~ 164.5 and 164.6 mV at a scan rate of 5 mV s⁻¹ in both catholyte and anolyte, respectively, demonstrating excellent electro-catalytic activity. Furthermore, single cell-based VRFBs using symmetric SCF-1600//SCF-1600 pairs revealed a considerably high energy efficiency of 86.8%, which is 10.3% higher than that of VRFB using commercial carbon felt electrodes (76.5%). After 100th galvanostatic charge/discharge cycles, the capacity retention of 91% that was achieved, verified the long-term cycling stability. Our study suggest that the suitable heteroatom contents and carbon microstructures of electrode material can enhance the electrochemical performances, resulting in high electro-catalytic activity for vanadium redox flow batteries.

在这项研究中，我们使用商用丝织物通过简单的热解过程制造了丝蛋白衍生的碳织物 (SCF) 作为钒氧化还原液流电池 (VRFB) 的电极，无需任何后处理。热解后，SCFs 的固有织物形态得以保持，从而形成高度大孔结构。此外，即使在 1600°C 以上的高温下热解后，SCF 在其表面也含有足够的杂原子，如氧和氮，这源于它们的蛋白质性质。结果，通过在 1,600 °C 下加热制备的 SCF 电极在5 mV s ^-1的扫描速率下表现出低至 ~ 164.5 和 164.6 mV 的峰值电位分离 (ΔE _p ) 值分别在阴极电解液和阳极电解液中显示出优异的电催化活性。此外，使用对称 SCF-1600//SCF-1600 对的基于单细胞的 VRFB 显示出相当高的 86.8% 的能量效率，比使用商业碳毡电极的 VRFB (76.5%) 高 10.3%。经过第 100 次恒电流充放电循环后，达到 91% 的容量保持率，验证了长期循环稳定性。我们的研究表明，电极材料合适的杂原子含量和碳微结构可以提高电化学性能，从而使钒氧化还原液流电池具有较高的电催化活性。