Strain induced optical properties of perovskite LaFeO3

Abstract

Tuning the properties of perovskite metal oxide by varying the crystal structure leads to many functional applications. Here strain induced by an external matrix like reduced graphene oxide (RGO) in the crystal structure of LaFeO3 (LFO) and its related optical properties are investigated. X-ray diffraction technique is used to find the strain in the crystal structure of graphene-LFO (GL) composite. The band gap and band tailing energy of the composites are determined by applying modified Kubelka-Munk function on UV-Vis DRS data. The steady-state fluorescence emission spectra of the samples show a monotonic decrease with increase in concentration of RGO. GL composites show enhanced photocatalytic degradation of RhodamineB (RhB) dye under solar spectrum irradiation. Variations in lifetime, fluorescence intensity and photocatalytic activity of GL composites are explained in terms of intermediate bands produced by RGO and associated radiation-less transitions of photoexcited electrons. RGO induced strain and tuning the optical properties of perovskites can provide a pathway to engineer new multifunctional materials in optoelectronic applications.