Electro-catalytic hydrogen evolution and magnetic behavior of N-doped-rGO supported NixPy

Abstract

Search for cost effective, earth abundant electrocatalysts for hydrogen generation through water splitting is the challenge of the hour whereas multifunctional applicability of the materials is the extremely sought issue for multi-tasking smart materials. In this work, nitrogen doped reduced graphene oxide (N-rGO) supported nickel phosphide (NixPy) nanomaterial has been prepared and characterized. Details electrocatalytic measurements exhibit the commendable performance of the composite materials against hydrogen evolution reaction in acid medium. The reduction of the required overpotential for reaching 10 mA/cm2 from 265 mV (NixPy) to 248 mV (NixPy/N-rGO) is observed in 0.5 M H2SO4 solution which proves the benefit for attaching N-rGO with NixPy. The electrochemical active surface area measurement also ascertains the quality of the composite and the enhancement of an active surface area is attributed to the attachment of N-rGO matrix. Furthermore, the NixPy/N-rGO composite confirms it’s stability in the acidic medium for 1200 min at 248 mV without any significant loss of current. Ground state ferromagnetic behavior has been demonstrated by NixPy/N-rGO in sharp contrast to the paramagnetic behavior exhibited by the bare NixPy nanoclusters at low temperature. Thus, the N-rGO matrix supported NixPy manifests both electrocatalytic proficiency and magnetic ordering with potential application in the future green energy as well as in data storage technologies.