Structural Design of Amorphous CoMoPxwith Abundant Active Sites and Synergistic Catalysis Effect for Effective Water Splitting
Structural Design of Amorphous CoMoPxwith Abundant Active Sites and Synergistic Catalysis Effect for Effective Water Splitting
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DOI：
10.1002/adfm.202003889
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发表时间：
2020-09-03
影响因子：
19
通讯作者：
Lee, Jinwoo
中科院分区：
文献类型：
--
作者：
Huang, Huawei;Cho, Ara;Lee, Jinwoo
为此，提出了一种合成非晶态双金属磷化物(a-CoMoPx/CF)的结构设计原则，以有效地催化分解水。采用多孔Co-MOF/CF和缺陷CoMoO4/CF作为结构诱导模板，引入丰富的缺陷和大的空洞，促进非晶态a-CoMoPx/CF的形成。理论计算揭示了基于双金属组分的协同催化机理。层次化纳米片阵列与非晶态结构相结合，提供了卓越的传质能力和充分暴露的原子，增加了电化学活性表面积(ECSA)。A-CoMoPx/Cf具有良好的析氢催化活性，具有很低的过电位59 mV，在碱性条件下的电流密度为10 mA cm(-2)。以a-CoMoPx/Cf为阴极和阳极的全电解器的催化性能与贵金属催化剂(Pt/C-Cf//RuO_2-Cf)相当，在1.581 V的电压下可达到10 mA cm(-2)，在100 mA cm(-2)下稳定运行100h以上。这些发现为设计稳定的稀土元素结构催化剂提供了新的概念，用于大规模应用与能量转换相关的电催化过程。
Herein, a structural design principle is presented to synthesize amorphous bimetallic phosphides (a-CoMoPx/CF) to efficiently catalyze water splitting. Porous Co-MOF/CF and defective CoMoO4/CF are used as structure-inducing templates to introduce rich defects and large voids that facilitate the formation of amorphous a-CoMoPx/CF. Theoretical calculations reveal a synergistic catalytic mechanism that is based on the bimetallic components. Hierarchical nanosheet arrays combined with amorphous structures provide a superior mass transfer capacity and fully exposed atoms, increasing the electrochemical active surface area (ECSA). The structural advantages and the synergistic catalytic effect of the bimetallic components generate a-CoMoPx/CF with excellent catalytic activity for the hydrogen evolution reaction (HER), displaying a very low overpotential of 59 mV and delivering a current density of 10 mA cm(-2)under alkaline conditions. A full electrolysis apparatus with a-CoMoPx/CF as both cathode and anode shows a catalytic performance comparable to that of a noble metal-based catalyst set-up (Pt/C-CF // RuO2-CF), achieving 10 mA cm(-2)at a potential of 1.581 V and stable operation at 100 mA cm(-2)for more than 100 h. These findings provide a novel concept to design stable structured catalysts based on earth-abundant elements for the large-scale application of electrocatalysis processes related to energy conversion technologies.