Directly grown monolayer MoS2 on Au foils as efficient hydrogen evolution catalysts

TL;DR

This paper demonstrates a scalable method to grow high-quality monolayer MoS2 on Au foils, which acts as an efficient electrocatalyst for hydrogen evolution with superior activity due to abundant active sites and excellent electron coupling.

Contribution

It introduces a novel low pressure chemical vapor deposition process for growing large-area monolayer MoS2 on Au foils, enhancing HER catalytic performance.

Findings

Monolayer MoS2 on Au foils shows low Tafel slope (61 mV/decade).

Exchange current density achieved is 38.1 μA/cm².

The catalyst exhibits superior HER activity compared to nanoparticles or multilayer MoS2.

Abstract

Synthesis of monolayer MoS2 is essential for fulfilling the potential of MoS2 in catalysis, optoelectronics and valleytronics, etc. Herein, we report for the first time the scalable growth of high quality, domain size tunable (edge length from ~ 200 nm to 50 {\mu}m), strictly monolayer MoS2 on commercially available Au foils, via a low pressure chemical vapor deposition method. The nanosized triangular MoS2 flakes on Au foils was proved to be an excellent electrocatalyst for hydrogen evolution reaction (HER), featured by a rather low Tafel slope (61 mV/decade) and a supreme exchange current density (38.1 {\mu}A/cm2). The abundant active edge sites and the excellent electron coupling between MoS2 and Au foils account for the extraordinary HER activity. Our work presents a sound proof that strictly monolayer MoS2 assembled on a well selected electrode can manifest comparable or even superior HER property than that of nanoparticles or few-layer MoS2 electrocatalyst.