Pt Atomic Layers Boosted Hydrogen Evolution Reaction in Nonacidic Media

Abstract

Pt-based electrocatalysts exhibit high performance toward hydrogen evolution reaction (HER) since they can boost sluggish kinetics of water dissociation. To develop efficient Pt catalysts in nonacidic media, Pt electrocatalysts with a Rh core and a shell of a few Pt atomic layers (Rh@PtnL, n = 1, 2, 2.6) are designed. Ultrathin Pt atomic layers on a Rh core modulate electronic structures of Rh@PtnL electrocatalysts, generating a combined effect of ligand, compressive strain, and electron transfer. The Rh@PtnL electrocatalysts thus offer significantly higher HER activity in alkaline and neutral media than the RhPt alloy, Rh/C, and commercial Pt/C catalysts. The overpotential of a Rh@Pt2L electrocatalyst is only 5 mV at 10 mA cm−2 in 1.0 M KOH. The density functional theory calculations confirm that the excellent HER activity of this Rh@Pt2L electrocatalyst in nonacidic media is attributed to an enhanced hydrogen desorption and a decreased energetic barrier during the hydrogen generating process. These Rh@PtnL electrocatalysts shed the light on the design of advanced catalysts to efficiently produce green hydrogen in nonacidic media.