Direct synthesis of two-dimensional MoS2 on p-type Si and application to solar hydrogen production

Abstract

Transition metal dichalcogenides (TMDs) are promising two-dimensional (2D) materials, and MoS2 has been specifically utilized in electronic devices and integrated circuits. However, the direct synthesis of MoS2 on traditional semiconductors, such as silicon, remains challenging due to the hydrophobic surface of nonoxide wafers (e.g., Si, GaAs, and InP). Herein, a novel, facile, reliable, and one-step method for the direct synthesis of single-crystal MoS2 on a p-Si wafer via hybrid thermolysis is proposed. To demonstrate the applicability of the proposed method, a MoS2/p-Si heterojunction was fabricated and used for solar-driven hydrogen production. The as-fabricated n-MoS2/p-Si heterojunction exhibited a benchmark current density of −13.5 ± 1 mA/cm2 at 0 V and an onset potential of +0.02 V. This method reliably and efficiently produced high-quality MoS2 crystals on a wafer scale and is sufficiently simple to overcome the challenges associated with previous approaches. The method developed herein represents a tremendous advancement in the fabrication of 2D electronic devices. © 2019, The Author(s).