Atomic layer deposited Pt nanoparticles on functionalized MoS2 as highly sensitive H2 sensor

A novel route to fabricate functional interface between highly-dense platinum (Pt) catalysts and 2D MoS2 using atomic layer deposition (ALD) and plasma treatment is proposed. Densely-decorated ALD Pt nanoparticles on plasma-functionalized MoS2 is evaluated as H2 sensor, resulting in highly sensitive detection of nonpolar H2 with the lower detection limit down to 2.5 ppm. [Display omitted] •Atomic layer deposited(ALD) Pt on plasma-treated MoS2 as a sensitive H2 sensor.•Effects of plasma treatment and Pt ALD cycles on sensor performance are elucidated.•ALD Pt-MoS2 H2 sensor shows high sensitivity(greater than400) and low detection limit(2.5 ppm).•ALD Pt-MoS2 sensor shows excellent selectivity and long-term stability for 4 weeks. Hydrogen gas (H2) has garnered significant attention as an alternative clean energy source, and its sensitive detection is essential to prevent explosions due to leakage in storage systems. Molybdenum disulfide (MoS2), which exhibits a large surface area-to-volume ratio from atomically thin two-dimensional (2D) structure, has attracted attention as a suitable H2 sensing material. However, pristine MoS2 exhibits low sensitivity to nonpolar H2. This paper demonstrates a decoration method for platinum (Pt) catalysts on 2D MoS2 using atomic layer deposition (ALD) and its application to fabricate highly sensitive H2 sensors. Additionally, to induce homogeneous distribution of Pt nanoparticles on chemically inert MoS2 surfaces, oxygen plasma pretreatment is employed as the MoS2 surface functionalization method. Consequently, highly sensitive detection of H2 with the sensitivity over 400 and the lower detection limit set to 2.5 ppm, is achieved using ALD Pt-decorated MoS2, and a sensing mechanism is proposed.