Ding Yu, Xue Qi, Hong Qing-Ling, Li Fu-Min, Jiang Yu-Cheng, Li Shu-Ni, Chen Yu
Key Laboratory of Macromolecular Science of Shaanxi Province, Key Laboratory of Applied Surface and Colloid Chemistry (Ministry of Education), Shaanxi Key Laboratory for Advanced Energy Devices, Shaanxi Engineering Lab for Advanced Energy Technology, School of Materials Science and Engineering, Shaanxi Normal University, Xi'an 710062, PR China.
School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an 710062, PR China.
ACS Appl Mater Interfaces. 2021 Jan 27;13(3):4026-4033. doi: 10.1021/acsami.0c20554. Epub 2021 Jan 17.
The sluggish reaction kinetics of the anodic oxygen evolution reaction increases the energy consumption of the overall water electrolysis for high-purity hydrogen generation. In this work, ultrathin cobalt sulfide nanosheets (CoS-NSs) on nickel foam (Ni-F) nanohybrids (termed as CoS-NSs/Ni-F) are synthesized using cyanogel hydrolysis and a sulfurization two-step approach. Physical characterizations reveal that CoS-NSs with a 1.7 nm thickness have abundant holes, implying the big surface area, abundant active edge atoms, and sufficient active sites. Electrochemical measurements show that as-synthesized CoS-NSs/Ni-F have excellent electrocatalytic activity and selectivity for ethanol oxidation reaction and hydrogen evolution reaction. Due to their bifunctional property of CoS-NSs/Ni-F nanohybrids, a symmetric CoS-NSs/Ni-F∥CoS-NSs/Ni-F ethanol electrolyzer can be effectively constructed, which only requires a 1.48 V electrolysis voltage to reach a current density of 10 mA cm for high-purity hydrogen generation at the cathode as well as value-added potassium acetate generation at the anode, much lower than the electrolysis voltage of traditional electrochemical water splitting (1.64 V).
阳极析氧反应迟缓的反应动力学增加了用于生成高纯度氢气的整体水电解的能量消耗。在这项工作中，采用氰凝胶水解和硫化两步法合成了泡沫镍（Ni-F）纳米杂化物上的超薄硫化钴纳米片（CoS-NSs）（称为CoS-NSs/Ni-F）。物理表征表明，厚度为1.7 nm的CoS-NSs有大量孔洞，这意味着其具有大表面积、丰富的活性边缘原子和足够的活性位点。电化学测量表明，所合成的CoS-NSs/Ni-F对乙醇氧化反应和析氢反应具有优异的电催化活性和选择性。由于CoS-NSs/Ni-F纳米杂化物具有双功能特性，因此可以有效地构建对称的CoS-NSs/Ni-F∥CoS-NSs/Ni-F乙醇电解槽，该电解槽仅需1.48 V的电解电压就能在阴极实现10 mA cm的电流密度以生成高纯度氢气，并在阳极生成增值产物醋酸钾，这远低于传统电化学水分解的电解电压（1.64 V）。
