Controllable Epitaxial-like Growth of Bi<sub>2</sub>S<sub>3</sub>/MoS<sub>2</sub> Hybrid Aerogel Nanostructures for Sensitive NO<sub>2</sub> Detection at Room Temperature
Li Liu, Yang Gao, Qinghua Hu
Abstract
Constructing heterogeneous interfaces on a nanoscale that can prominently improve the gas-sensing properties has been comprehensively reported. However, the effect of parallel heterostructures formed by unique synthetic means on nitrogen dioxide room-temperature sensing properties still needs to be clarified, which hinders the development of heterostructured hybrid materials in the field of gas sensing. In this study, large-sized MoS 2 was parallel-wrapped on the surface of nanoscale Bi 2 S 3 rods, and then, the Bi 2 S 3 /MoS 2 nanocomposite aerogels were formed by freeze drying and calcination. The NO 2 sensing performance of the hybrids and possible surface processes at room temperature have been investigated and deduced. The as-prepared nanocomposite aerogels (Bi 2 S 3 /MoS 2 -2) exhibited a larger specific surface area, a mass of active defect sites, and a higher charge density, thus possessing 15- and 20-times higher response than that of pristine MoS 2 nanosheets and Bi 2 S 3 nanorods, respectively. This study provides an efficient way to synthesize large-area parallel heterostructures between two bis-sulfides (Bi 2 S 3 and MoS 2 ), leading to excellent NO 2 gas sensing performance.