Fabricating In2O3 NPs /MWCNTs heterostructure photodetectors by laser ablation method

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.