Exfoliated MoSe₂ Nanosheets Doped on the Surface of ZnO Nanorods for Hydrogen Sensing Applications

Abstract

Molybdenum diselenide (MoSe2) is a promising gas sensing material due to its large surface-to-volume ratio, narrow band gap, and excellent absorptions. However, MoSe2-based gas sensors possess inferior gas response and recovery at room temperature. In this context, assembly of hybrid structures can be an effective technique to stimulate the intrinsic structural and electronic properties of MoSe2 nanosheets (NSs). Herein, we report interfacial science and engineering to design a unique p–n hetero nanostructure for the first time using MoSe2NSs doped with ZnO nanorods (ZNRs) through facile methods. The systematic material analyses revealed that MoSe2 is consistently coated on the surface of ZNRs in this present hybrid combination. The MoSe2-ZNRs hybrid structure exhibits an excellent sensitivity (∼60%), which is better than those of pristine MoSe2 NSs (20%) and ZNRs (10%) toward H2 gas. It was revealed that the finest doping of MoSe2 on the surface of ZNRs improves the H2 gas sensing properties when compared to that of pristine ZNRs. This can be ascribed to the structure–property correlation, synergistic interfacial effects, and p–n hybrid hetero junctions between exfoliated MoSe2 and ZNRs. The successful hybridization of the MoSe2-ZNRs hetero nanostructure paves the way to future opportunities on the hybridization and fabrication of MOS with TMDs gas sensors.