Hydrogen gas sensor based on SnO2 nanospheres modified with Sb2O3 prepared by one-step solvothermal route

Abstract

Abstract In this work, an ultra-low-cost and ecofriendly solvothermal strategy was employed to prepare gas-sensing materials for heterostructured p-Sb2O3/n-SnO2 nanospheres. The morphology, microstructure and other characteristics of the prepared products were comprehensively studied by several analyzers. The results show that the present SnO2 nanospheres modified with Sb2O3, exhibit exceptional mesoporous structures and high specific surface areas, as well as prominent thermal stability (only 0.02 % mass loss). For the first time, the cost-effective gas sensor based on Sb2O3/SnO2 nanospheres was fabricated, which maintained excellent gas-sensing behavior of 697 % towards 100 ppm H2 gas at operating temperature of 280 ℃, with a fast response/recovery time of 29.8/13.4 s, and the limit of detection was down to 100 ppb (S = 7.1 %). In addition, the gas sensor had quite consistency, reproducibility, long-term stability (over 40 days), and unique selectivity towards H2 gas. Investigations into a plausible gas-sensing mechanism imply that the p-n heterojunction, catalytic function of Sb2O3, mesoporous structures and high specific surface area synergistically induced the superior gas-sensing response. Undoubtedly, the present work may provide an outstanding strategy to improve H2 gas response in extremely environmental applications.