Robust NiCoP/CoP Heterostructures for Highly Efficient Hydrogen Evolution Electrocatalysis in Alkaline Solution

Abstract

Electrocatalytic hydrogen evolution reaction, the cornerstone of the emerging hydrogen economy, can be essentially facilitated by robustly heterostructural electrocatalysts. Herein, we report a highly active and stably heterostructural electrocatalyst consisting of NiCoP nanowires decorated with CoP nanoparticles on a nickel foam (NiCoP–CoP/NF) for effective hydrogen evolution. The CoP nanoparticles are strongly interfaced with NiCoP nanowires producing abundant electrocatalytically active sites. Combined with the integrated catalyst design, NiCoP–CoP/NF affords a remarkable hydrogen evolution performance in terms of high activity, enhanced kinetics, and outstanding durability in an alkaline electrolyte, superior to most of the Co (or Ni)-phosphide-based catalysts reported previously. Density functional theory calculations demonstrate that there is an interfacial effect between NiCoP and CoP, which allows a preferable hydrogen adsorption and thus contributes to the significantly enhanced performance. Furthermore, an electrolyzer employing NiCoP–CoP/NF as the cathode and RuO2/NF as the anode (NiCoP–CoP/NF||RuO2/NF) exhibits excellent water-splitting activity and outstanding durability, which is comparable to that of the benchmark Pt–C/NF||RuO2/NF electrolyzer.

Multi‐Phase Heterostructure of CoNiP/CoxP for Enhanced Hydrogen Evolution Under Alkaline and Seawater Conditions by Promoting H2O Dissociation

“…This result reveals that the optimal Co/Ni ratio to construct unique multi‐phase heterostructure can dramatically boost the catalytic activity. In addition, the catalytic performance of CoNiP/Co x P is much better than those of cobalt‐ and/or nickel‐based multi‐phase heterostructures at 10 mA cm −2 , such as CoP/NiCoP/NC (75 mV), [ 3d ] CoP/NiCoP nano tadpoles (133 mV), [ 8b ] NiCoPCoP/NF (73 mV), [ 28 ] Ni/NiCoP (125 mV), [ 19a ] and Ni 2 PNiSe 2 (66 mV), [ 29 ] and is the best among the non‐noble catalysts reported recently (Table S4, Supporting Information). To further investigate the HER activities, Tafel plots (Figure 4c and Figure S10b, Supporting Information) were obtained by plotting the overpotential against log(j) according to the Tafel equation (η = b × log(j) + a ).…”

Direct Growth of Highly Strained Pt Islands on Branched Ni Nanoparticles for Improved Hydrogen Evolution Reaction Activity

“…Simultaneously, the number of adjacent Pt-Ni atoms that are important for HER electrocatalysis would substantially increase. 22 Recently, other highly lattice mismatched core-shell nanoparticles have been synthesized by slow reduction and deposition of the secondary metal onto a core. 23,24 This strategy offers an opportunity to directly grow Pt onto Ni.…”

Interface Engineering of Binder‐Free Earth‐Abundant Electrocatalysts for Efficient Advanced Energy Conversion

“…Besides the nanoparticle‐on‐nanosheet structure, the nanoparticle‐on‐nanowire structure has also been extensively investigated. For instance, a binder‐free electrocatalyst, in which CoP nanoparticles were directly grown on nickel foam supported NiCoP nanowires, was developed . The as‐prepared electrocatalyst exhibited excellent catalytic activity toward HER with a low overpotential of 73 mV at 10 mA cm −2 .…”