Dual Vacancies Confined in Nickel Phosphosulfide Nanosheets Enabling Robust Overall Water Splitting

Abstract

Exploring highly efficient electrocatalysts for both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) is of great significance for addressing energy and environmental crises. Vacancy engineering has been regarded as a promising way to optimize the catalytic activity of electrocatalysts. Herein, we put forward a conceptually new dual Ni,S vacancy engineering on 2D NiPS3 nanosheet (denoted as V−NiPS3) by a simple ball‐milling treatment with ultrasonication. This material presents an ideal model for exploring the role of dual vacancies in improving the catalytic activity for overall water splitting. Structural analyses make clear that the formation of dual Ni,S vacancies regulates the electronic structure and catalytic active sites of NiPS3 nanosheet, leading to the superior HER/OER performance. Smaller overpotentials of 124 mV and 290 mV can be achieved at a current density of 10 mA cm−2 for HER and OER, respectively. The OER performance of V−NiPS3 is the best value among all state‐of‐the‐art NiPS3 catalysts. In addition, the assembled two‐electrode cell incorporating V−NiPS3 exhibits enhanced catalytic performance with a low cell voltage of 1.60 V at 10 mA cm−2. This work offers a promising avenue to improve the electrocatalytic performance of the catalysts by engineering dual vacancies for large‐scale water splitting.

Phosphorized CoNi2S4 Yolk‐Shell Spheres for Highly Efficient Hydrogen Production via Water and Urea Electrolysis

“…[24,32,34] TheP 2p spectrum of P-CoNi 2 S 4 (Figure 3f)o nly displays one doublet (133.52 eV,1 34.39 eV) assigned to the P-bonded with Co/Ni, no oxidized Ps pecies are observed. [31,37] This fully confirms the substitution characteristics of P, which will induce more electronic interactions for enriched Ni 3+ content, thereby promoting electrocatalytic performance.…”

Cobalt Telluride: A Highly Efficient Trifunctional Electrocatalyst for Water Splitting and Oxygen Reduction

“…Among these, transition metal compounds from the ferrous group elements (Fe, Co, Ni) have made a significant impact in this research area owing to their unprecedented high catalytic activity characterized by low overpotential. These transition metal compositions include oxides, hydroxides, carbides, nitrides, phosphides, and chalcogenides. − Among the transition metals, Co deserves special mention since it was predicted that modulating the d -electron density around the catalytic site, especially a half-filled e g orbital, will lead to more optimal charge transfer at the catalyst-water interface, making Co occupy top position of the Sabatier plot, exhibiting optimal rate for OER in alkaline medium . Accordingly, Co-oxides and hydroxides have been studied extensively for OER activity in alkaline medium. − In addition to oxides, other compositions of Co, specifically, N-C composites, − phosphides, , phosphates, , metal organic frameworks, − and chalcogenides, − have also been investigated as potential applicants for electrocatalytic water splitting.…”

Shining Light on Anion-Mixed Nanocatalysts for Efficient Water Electrolysis: Fundamentals, Progress, and Perspectives

“…While the P atoms enhance the electron-donating ability of X 2 2-, which encourages the redox https://doi.org/10.1007/s40820-021-00785-2 © The authors reactions of metal atoms [68]. Recently, numerous reports are available in the literature for TM-based phosphosulfides such as MoPS, PdPS, CoPS, FePS 3 , NiPS 3 , and so on [26,66,[139][140][141][142][143][144][145][146][147].…”