Liu Bin, Wang Feng-Ge, Li Wen-Jing, Qiao Wei-Zhen, Liu Xin, Luan Ren-Ni, Liu Chun-Ying, Dong Bin, Chai Yong-Ming
State Key Laboratory of Heavy Oil Processing, College of Chemistry & Chemical Engineering, China University of Petroleum (East China), Qingdao 266580, PR China.
State Key Laboratory of Heavy Oil Processing, College of Chemistry & Chemical Engineering, China University of Petroleum (East China), Qingdao 266580, PR China.
J Colloid Interface Sci. 2024 May;661:700-708. doi: 10.1016/j.jcis.2024.01.111. Epub 2024 Jan 24.
The incorporation of high-valence transition metal atoms into FeNi (oxy)hydroxides may be a promising strategy to regulate the intrinsic electronic states, thereby reducing the thermodynamic barrier and accelerating oxygen evolution reaction (OER). Here, a high-valence Mo atoms doping route is proposed by an efficient self-reconstruction strategy to prepare MoFeNi (oxy)hydroxides for efficient alkaline OER. By using borides (MoNiB) as sacrificial template and Mo source, FeNi (oxy)hydroxides nanoflakes embedded with high-valence Mo atoms (MoFeNi) is successfully synthesized, which can modulate the electron coordination to improve the intrinsic catalytic activity. Remarkably, the obtained MoFeNi exhibits extremely low overpotential (η = 252 mV and η = 288 mV) and small Tafel slope (18.35 mV dec). The robust catalyst can run stably for hours at 500 mA cm. Characterization results and theoretical calculations confirmed that the addition of high-valence Mo effectively modulated the intrinsic electronic structure of metal sites and optimized the adsorption/desorption energy of the intermediates, accelerating OER reactions kinetics. By coupling MoFeNi anode with Pt/C cathode, anion exchange membrane (AEM) electrolyser can operate stably at 500 mA cm with about less than 2.2 V. This research introduces a novel approach to develop ideal electrocatalysts through the incorporation of high-valence molybdenum species.
将高价过渡金属原子引入氢氧化铁镍中可能是一种很有前景的策略，用于调节其本征电子态，从而降低热力学势垒并加速析氧反应（OER）。在此，通过一种高效的自重构策略提出了一种高价钼原子掺杂途径，以制备用于高效碱性OER的钼铁镍氢氧化物。以硼化物（MoNiB）作为牺牲模板和钼源，成功合成了嵌入高价钼原子的氢氧化铁镍纳米片（MoFeNi），其可以调节电子配位以提高本征催化活性。值得注意的是，所制备的MoFeNi表现出极低的过电位（η = 252 mV和η = 288 mV）和较小的塔菲尔斜率（18.35 mV dec）。这种稳健的催化剂在500 mA cm下可稳定运行数小时。表征结果和理论计算证实，高价钼的加入有效地调节了金属位点的本征电子结构，优化了中间体的吸附/脱附能，加速了OER反应动力学。通过将MoFeNi阳极与Pt/C阴极耦合，阴离子交换膜（AEM）电解槽在500 mA cm下可稳定运行，电压约低于2.2 V。本研究通过引入高价钼物种，介绍了一种开发理想电催化剂的新方法。
