Preparation of a silicon heterojunction photodetector from colloidal indium oxide nanoparticles

•High performance In2O3 NPs/Si photodetector was prepared by laser ablation.•The photodetector has high sensitivity to visible and near IR.•XRD spectrum showed that In2O3 NPs is polycrystalline.•The optical band gap of In2O3 NPs is about 3.95 eV.

A colloidal indium oxide (In2O3) nanoparticles (NPs) were synthesized by using a Q-switched Nd:YAG laser ablation of indium target in water at room temperature. Optical absorption and x-ray diffraction (XRD) investigation of the prepared samples confirm the formation of In2O3 NPs. A solution-processed silicon heterojunction photodetector, fabricated by drop cast film of colloidal In2O3 NPs onto n-type single crystal silicon wafer, is demonstrated. I–V characteristics of In2O3 NPs/Si heterojunction under dark and illumination conditions confirmed the rectifying behavior and the good photoresponse. The built-in-voltage was determined from the C–V measurements which revealed an abrupt junction.