Synthesis and Characterization of N-doped Carbon Shell Coated Iron Phosphide Nanocatalyst for Hydrogen Evolution Reaction

Abstract

Abstract Synthesis and Characterization of N-doped Carbon Shell Coated Iron Phosphide Nanocatalyst for Hydrogen Evolution Reaction Taehyun Kim School of Chemical and Biological Engineering The Graduate School Seoul National University For the mass production of hydrogen, development of a highly durable, active, and affordable non-Pt electrocatalyst is essential to replace Ptbased electrocatalyst. Herein, we introduce a simple and effective synthesis of highly durable and active non-Pt electrocatalyst for hydrogen evolution reaction. Using iron oxide nanoparticles as a precursor, we synthesized carbon shell coated iron phosphide nanoparticles. By a single heat treatment of polydopamine coated ironoxide nanoparticles, carbonization of polydopamine coating and phosphidation of iron oxide nanoparticles to FeP nanoparticles are achieved simultaneously. In terms of their electrochemical performance, our nanoparticle catalysts show overpotential of 71 mV at 10 mA/cm2, which is compatible to that of commercial Pt catalyst, and remarkable durability under acidic conditions for 10,000 cycles without noticeable activity loss. The origin of long-term durability of carbon shell coated FeP nanoparticles was investigated experimentally. Extended X-ray adsorption fine structure analysis and electron energy loss spectroscopy line scan analysis reveal that the origin of long-term durability of our nanoparticles is resistance to surface oxidation, owing to the protective effect of carbon shell coating. Moreover, large-scale synthesis was conducted simply by scaling up the size of the reactor, which is an essential feature for mass production of hydrogen. Keywords: Nanoparticles, Hydrogen evolution reaction, Non-Pt electrocatalyst, Durability, Carbon shell coating, Oxidation resistance, Large scale synthesis Student Number: 2016-20993