Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6605261 | Electrochimica Acta | 2017 | 10 Pages |
Abstract
Nickel phosphide has been shown to be active toward hydrogen evolution reaction (HER). In this paper, we demonstrate the phase and composition controllable synthesis of nickel phosphide-based nanoparticles (NiP-based NPs) via a low-temperature phosphidation reaction (250 °C) using NaH2PO2 as the phosphorus source and the as-prepared Ni(OH)2 precursor as the nickel source. Interestingly, by changing the NaOH concentration and nickel source used to fabricate Ni(OH)2 precursors, we could adjust the phases and compositions of as-synthesized NiP-based nanocatalysts from Ni5P4, Ni2P to Ni12P5. The different steric hindrance and the electrostatic repulsion of synthesized β-Ni(OH)2 precursors result in the formation of three NiP phases with various Ni:P ratios. Electrochemical characterizations reveal that the NiP-based NPs with P-rich phase (Ni5P4+Ni2P) exhibit remarkable electrocatalytic HER property, with low overpotential (η) of 111 mV to reach a current density of 10 mA cmâ2 in a 0.5 M H2SO4 media, which is superior than those of pure Ni2P (η = 118 mV) and the Ni-rich NiP-based counterpart (Ni12P5+Ni2P) (η = 131 mV). This is attributed to the stronger ensemble effect of P and more active sites provided by P-rich NiP-based NPs. Our results demonstrate that by tailoring the surface properties of Ni(OH)2 precursors, the phases and compositions of NiP-based nanoparticles could be easily tuned, which provides a simple, economic, and green strategy to optimize the HER performance of transition metal phosphide-based electrocatalysts.
Related Topics
Physical Sciences and Engineering
Chemical Engineering
Chemical Engineering (General)
Authors
Ruiqi Zhou, Jinfeng Zhang, Zelin Chen, Xiaopeng Han, Cheng Zhong, Wenbin Hu, Yida Deng,