Fabricating In2O3 NPs /MWCNTs heterostructure photodetectors by laser ablation method

Abstract

In this study, we used a one-step laser ablation method to combine In₂O₃ colloidal nanoparticles with multi-walled carbon nanotubes (MWCNTs) to create an In₂O₃ NPs-MWCNTs heterostructure for photodetectors. X-Ray Diffraction (XRD) analysis of the prepared samples revealed that the In₂O₃ NPs/MWCNTs nanostructure contained graphite peak at the (002) plane and In₂O₃ NPs crystalline peaks which are indexed to body-centred cubic phase. Transmission electron microscope (TEM) investigation revealed that In₂O₃ nanoparticles have a spherical shape nanoparticle with an average size of 20 nm, and 33 nm for In₂O₃ NPs -MWCNTs nanostructure. UV–Vis test showed that the optical energy gap of the In₂O₃ NPs decreased from 3.2 to 2.7 eV after incorporating CNTs. The I–V characteristics for the In₂O₃ NPs/Si and In₂O₃ NPs-decorated MWCNTs/Si photodetector were investigated under both dark and illumination cases. The responsivity of the In₂O₃ NPs/Si photodetector showed an increase from 0.43 to 1.15 A/W after introducing CNTs at a wavelength of 450 nm. The fabricated photodetector showed a high sensitivity for Vis–NIR detection. The limit detection of In₂O₃ NPs -MWCNTs/Si photodetector was determined to be 3.39 × 10¹¹ Jones at 450 nm.