Zheng Yunhua, Hu Huiting, Zhu Yao, Rong Jian, Zhang Tao, Yang Dongya, Wen Qi, Qiu Fengxian
School of Chemistry and Chemical Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013, China.
School of Environmental and Safety Engineering, Changzhou University, Changzhou 213164, China.
Inorg Chem. 2022 Sep 12;61(36):14436-14446. doi: 10.1021/acs.inorgchem.2c02375. Epub 2022 Aug 29.
Electrocatalytic water splitting is considered a promising approach to obtain clean and sustainable hydrogen energy. The integration of optimal nanoarchitecture and multicomponent synergy has been a significant factor for designing a bifunctional electrocatalyst to promote the cathodic hydrogen evolution reaction (HER) and anodic oxygen evolution reaction (OER). In particular, the charge migration, mass transfer, and gas release rate in the catalyzing process are closely correlated with the architecture of the catalyst. Here, ZIF-67-derived N-doped carbon nanofiber-supported (NiCo)S nanosheet [(NiCo)S/NCNF] as a bifunctional electrocatalyst was synthesized using electrospinning, template etching, and subsequent gas sulfidation method. The hierarchical hybrid nanofiber with inner hollow cubes and outer nanosheets provides easy electron penetration, high charge/mass transportation efficiency, and robust structure stability. Furthermore, the MOF-derived carbon-encapsuled bimetal-sulfide and the synergistic effect of double active centers are conducive to an exceptional performance, showing low overpotentials of 177 and 203 mV to drive a current density of 10 mA cm and robust stability for the HER and OER, respectively. Meanwhile, the (NiCo)S/NCNF electrodes exhibit a small voltage of 1.61 V for overall water splitting activity with an electrolyzer cell at current densities of 10 mA cm over 12 h. This work presents novel insights into the bifunctional catalyst for promoting the overall water splitting via a MOF-derived nanoarchitecture and multicomponent synergy.
电催化水分解被认为是一种获取清洁且可持续氢能的有前景的方法。优化的纳米结构与多组分协同作用的结合一直是设计双功能电催化剂以促进阴极析氢反应（HER）和阳极析氧反应（OER）的一个重要因素。特别是，催化过程中的电荷迁移、传质和气体释放速率与催化剂的结构密切相关。在此，通过静电纺丝、模板蚀刻及后续的气体硫化法合成了ZIF-67衍生的氮掺杂碳纳米纤维负载的（NiCo）S纳米片[（NiCo）S/NCNF]作为双功能电催化剂。具有内部空心立方体和外部纳米片的分级杂化纳米纤维提供了便捷的电子渗透、高电荷/质量传输效率以及稳健的结构稳定性。此外，金属有机框架衍生的碳包覆双金属硫化物以及双活性中心的协同效应有助于实现优异的性能，在驱动10 mA cm的电流密度时，HER和OER的过电位分别低至177和203 mV，且具有稳健的稳定性。同时，在10 mA cm的电流密度下，（NiCo）S/NCNF电极在12小时内用于全水解活性的电解槽电压仅为1.61V。这项工作通过金属有机框架衍生的纳米结构和多组分协同作用，为促进全水解的双功能催化剂提供了新的见解。
