Amorphous FeNi alloy nanoparticles encapsulated in N doped carbon shell induced by laser irradiation with enhanced electrocatalytic activity for water oxidation

Abstract

Tuning crystal structure of metal nanomaterials is an effective approach to optimize electrocatalytic performance. Here, we employ amorphous FeNi alloy nanoparticles encapsulated in N doped carbon shell (A-FeNi@NC) as an efficient electrocatalyst for oxygen evolution reaction (OER) via laser irradiation in H2O. The formation mechanism of amorphous FeNi alloy is due to the rapid heating and cooling rate result from the pulse laser. The following electrochemical measurements indicate that A-FeNi@NC displays much better OER activity compared with the conventional crystalline FeNi alloy nanoparticles encapsulated in N doped carbon shell (C-FeNi@NC). We proposed that amorphous FeNi alloy possess favorable electronic property to optimize electronic state of the external carbon shell and give rise to a higher electrocatalytic activity towards OER. The optimized electronic state of the external carbon shell commonly exists in other amorphous transition metal include FeCo, CoNi and Ni, give birth to a series of efficient electrocatalysts for OER.