Facile synthesis and enhanced gas sensing properties of grain size-adjustable In2O3 micro/nanotubes

Without accurately controlling the ratio of reactants, indium oxide (In2O3) micro/nanotubes are successfully fabricated by a facile coaxial electrospinning route and a subsequent annealing treatment. The micro/nanotubes consist of In2O3 nanocrystals with primary grain sizes of 10-23 nm and present rough surfaces. The grain sizes of In2O3 micro/nanotubes can be adjusted by the calcination temperature. The In2O3 micro/nanotubes present grain size-dependent gas sensing properties. The sensors based on In2O3 micro/nanotubes calcined at 400 °C (NT400) show better HCHO gas sensing performances in comparison with the sensors based on In2O3 micro/nanotubes calcined at 600 °C (NT600) and 800 °C (NT800). The facile fabrication method and excellent gas sensing performances make as-prepared In2O3 micro/nanotubes developed for HCHO gas detection in practice.