Glycerin-assisted assembly of hierarchical In2O3 /ZnO micro-flowers with an in-plane folded shell structure for chemiresistive triethylamine detection

Extraordinary behavior of semiconductor metal oxide-based gas sensors is broadly applied in gas supervision, but they usually suffer from high operating temperature, gas cross-sensitivities and response fluctuations, limiting their use in expanding applications. Herein, hierarchical In2O3/ZnO micro-flower with in-plane folded shells heterostructure was successfully prepared through simple glycerol-assisted solvothermal method followed by a subsequent pyrolysis treatment. The optimized In2O3/ZnO-0.5 heterostructure with specific In/Zn molar ratio exhibits excellent triethylamine (TEA) sensing capability at 200 degrees C, including a high response of 34.87 towards 100 ppm TEA, superb gas selectivity, fast response and recovery time (62 s/33 s) and prolonged cyclic stability, ascribing to the well assembly of the unique In2O3/ZnO n-n heterojunction with plentiful reactive sites, which markedly promote the absorption of TEA and the surface gas sensitive reaction with oxygen species at the close contacted interface between In2O3 and ZnO. This work demonstrates a stable method for feasible manufacturing of In2O3/ZnO heterostructure with intriguing multi-level micro-nanostructure for highly sensitive TEA gas sensing application.