Rational synthesis of phosphorous rich iridium diphosphide (IrP2) nanostructures for electrochemical H2S detection

Abstract

Although iridium diphosphide (IrP2) has emerged as a promising electrocatalyst, the harsh synthetic conditions requiring high temperature (≥ 850 ℃) limits its wide application. This paper demonstrates a facile synthetic approach of single-phase IrP2 nanoparticles under a mild condition. Instead of commonly used iridium chloride precursors (e.g., IrClx), Ir(OH)3 formed via acid/base precipitation reaction was employed as the iridium source. The following phosphorization step at 650 °C under argon atmosphere successfully produced IrP2 nanoparticles. Moreover, the electroactivity of as-prepared IrP2 nanoparticles for electrochemical oxidation of hydrogen sulfide (H2S) was investigated for the first time. IrP2 nanoparticles showed an excellent amperometric response to H2S with ca. 2.5-fold greater sensitivity than iridium phosphide (Ir2P), presenting the feasibility of IrP2 as an efficient electrode material for electrochemical H2S sensing. © 2023 Elsevier B.V.