The Preparation of Iridium-Based Catalyst with Different Melting Point-Metal Nitrate and Its OER Performance in Acid Media

Abstract

AbstractOxygen evolution reaction (OER) is the main factor limiting the large-scale development of proton-exchange membrane (PEM) hydrogen production. It is urgent to develop catalysts with excellent OER catalytic performance and stability. Herein, several Iridium-based catalysts were prepared by simple mixing and calcination, the OER properties of catalysts with different melting points of nitrates as calcinating additives were investigated. The RbNO3 treated catalyst displayed a low overpotential(η) of 297.6 mV versus RHE, which is lower than the catalyst calcinated without nitrate (323.8 mV vs. RHE). Moreover, the RbNO3 treated catalyst displayed good acid stability over 20 h Chronopotentiometric test. The high OER catalytic activity and stability of RbNO3 treated catalyst may be attribute to the smaller nanoparticle morphology, pure IrO2 structure and high electrochemical surface area (ECSA), which increase the number of active sites and the intrinsic catalytic activity. This work indicated that the catalyst with excellent OER performance can be obtained by selecting nitrate with moderate melting point as the calcinating additive. Nitrates (like RbNO3) treated catalyst with excellent catalytic activity and stability has good application prospect in hydrogen production of PEM water splitting.