Enhancing hydrogen evolution reaction of confined monodispersed NiSe2−X nanoparticles by high-frequency alternating magnetic fields

Abstract

Introduction of alternating magnetic field (AMF) to electrocatalytic process has been proved an effective strategy for significantly enhancing catalytic performance of magnetic nanoparticles (NPs) electrocatalysts. Coupling AMF with currently highly promising monodispersed NPs electrocatalysts could be an interesting tactics. However, magnetic heating effect under AMF may cause agglomeration and even falloff of NPs, and how to efficiently and stably utilize AMF in monodispersed NPs electrocatalysts to enhance the catalytic performance is an urgent issue. In this work, room-temperature ferromagnetism is introduced into NiSe2−X nanoparticle by vacancy engineering, and proposes a feasible design to confine monodispersed ultra-small NiSe2−X NPs in an amorphous carbon matrix. Under AMF, the spin flips of the magnetic domains in confined NiSe2−X NPs generate magnetic heating related to Néel relaxation, which achieve rapid local heating of NiSe2−X NPs electrocatalyst and greatly improves hydrogen evolution reaction performance (a significantly increase of current density by ∼400 %). This work provides new ideas for the preparation of ultra-small monodispersed NPs electrocatalysts that can utilize AMF to enhance catalytic performance, and has an important significance in accelerating clean energy production.