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 In 2 O 3 /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 In 2 O 3 /ZnO-0.5 heterostructure with specific In/Zn molar ratio exhibits excellent triethylamine (TEA) sensing capability at 200 ℃, 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 In 2 O 3 /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 In 2 O 3 and ZnO. This work demonstrates a stable method for feasible manufacturing of In 2 O 3 /ZnO heterostructure with intriguing multi-level micro-nanostructure for highly sensitive TEA gas sensing application.