Ghosh Sirshendu, Kadam Sunil R, Kolatkar ShayLee, Neyman Alevtina, Singh Chanderpratap, Enyashin Andrey N, Bar-Ziv Ronen, Bar-Sadan Maya
Department of Chemistry, Ben-Gurion University, Beer-Sheva 8410501, Israel.
Institute of Solid-State Chemistry UB RAS, 620990 Ekaterinburg, Russian Federation.
ACS Appl Mater Interfaces. 2022 Jan 12;14(1):581-589. doi: 10.1021/acsami.1c16755. Epub 2021 Dec 28.
Bifunctional electrocatalysts for efficient hydrogen generation from water splitting must overcome both the sluggish water dissociation step of the alkaline hydrogen evolution half-reaction (HER) and the kinetic barrier of the anodic oxygen evolution half-reaction (OER). Nickel phosphides are a promising catalysts family and are known to develop a thin active layer of oxidized Ni in an alkaline medium. Here, NiP was recognized as a suitable platform for the electrochemical production of γ-NiOOH─a particularly active phase─because of its matching crystallographic structure. The incorporation of tungsten by doping produces additional surface roughness, increases the electrochemical surface area (ESCA), and reduces the energy barrier for electron-coupled water dissociation (the Volmer step for the formation of H). When serving as both the anode and cathode, the 15% W-NiP catalyst provides an overall water splitting current density of 10 mA cm at a cell voltage of only 1.73 V with good durability, making it a promising bifunctional catalyst for practical water electrolysis.
用于高效水分解制氢的双功能电催化剂必须克服碱性析氢半反应（HER）中缓慢的水离解步骤以及阳极析氧半反应（OER）的动力学障碍。磷化镍是一类很有前景的催化剂，已知在碱性介质中会形成一层薄的氧化镍活性层。在此，NiP因其匹配的晶体结构而被认为是电化学制备γ-NiOOH（一种特别活跃的相）的合适平台。通过掺杂引入钨会产生额外的表面粗糙度，增加电化学表面积（ESCA），并降低电子耦合水离解的能垒（形成H的Volmer步骤）。当用作阳极和阴极时，15% W-NiP催化剂在仅1.73 V的电池电压下提供10 mA cm的全水分解电流密度，且具有良好的耐久性，使其成为一种有前景的用于实际水电解的双功能催化剂。
