Graphene oxide:Fe2O3 nanocomposites for photodetector applications: experimental and ab initio density functional theory study

Abstract

In this report, a GO:Fe₂O₃ nanocomposite was synthesized using a one-step covalent attachment approach using a sol–gel technique. The optical absorbance, photoconductive, photo-capacitive, and electrical properties were obtained using spectroscopy, and current–voltage (I–V) measurements. An enhanced optical absorbance with corresponding band gap reduction is observed when Fe₂O₃ nanoparticles are incorporated in GO. A corresponding enhanced photoconductance in the order of ×10¹ was observed due to the impact of band gap narrowing. The enhanced photoconductivity and photo-capacitance can be attributed to energy and charge transfer between GO and Fe atoms, leading to the generation of photo-induced excitons. Density function theory calculations indicate increased charge transfer when GO is doped with Fe–O atoms, which is consistent with experimental data. The observed results could potentially enable the use of GO:Fe₂O₃ nanocomposites for photodetectors and other optoelectronic applications.