Preparation of Ni2P nanochains with controllable geometry for the hydrogen evolution reaction by application of a high magnetic field

Abstract

In this work, a new method for controlling the morphology of Ni2P materials by using a high magnetic field (HMF) was proposed. In HMF, the Ni2P nanoparticles become smaller and self-assemble into one-dimensional nanochain. The nucleation, growth, and assembly mechanism of Ni2P in HMF was revealed. Thermodynamic calculations show that the magnetic Gibbs free energy of the reaction process increases by 219 kJ mol−1 in 6T HMF and the saturation magnetization of Ni2P is 12 times higher than without HMF. In addition, the obtained Ni2P nanochains exhibit better electrocatalytic activity than Ni2P nanoparticle, the overpotential of Ni2P nanochain was 231 mV lower than that of Ni2P particles (200 mA cm−2). The theoretical and experimental results both indicate that magnetic field can control material structure and properties effectively.