Synthesis of flower-like S-doped SnO2 hierarchical structure for gas sensing application at room temperature

Abstract

Ammonia is one of the most common gases in life, which is produced in industrial emissions and agricultural activities. Therefore, effective detection of ammonia at low concentrations is vital for human health. Tin disulfide (SnS2) by virtue of its physical affinity and high surface area has become a promising material for gas sensing applications. The flower-like S-doped SnO2 3D hierarchical structure was succeeded in preparation via a two-step method. A variety of methods such as XRD, SEM, and TEM were utilized to characterize the prepared materials for the investigation of their surface morphological characteristics and elemental content. The morphological characterization analysis indicated that the prepared material was a self-assembled hierarchical flower-like SnS2 modified by SnO2 nanoparticles. In addition, the results from the elemental composition analysis showed the existence of Sn, O, and S elements in the material. Through experiments, we further tested the sensitivity, selectivity, and long-term stability of the S-doped SnO2 gas-sensitive material against NH3 at room temperature, and analyzed its sensing mechanism. As a result, the S-doped SnO2 was tested with a response value of 3.6 for 50 ppm ammonia’s outstanding performance in terms of selectivity and long-term stability. This work highlights the advantages of flower-like S-doped SnO2 3D hierarchical structures for NH3 sensors.