Visible light driven LaFeO3 nano sphere/RGO composite-photocatalysts for efficient water decomposition reaction

Abstract

RGO loaded on LaFeO3 nano sphere (GLFO) has been designed with greater stability in order to promote the photocatalytic activity towards water splitting by tuning the optical band gap of LFO and reducing the e(-) and h(+) recombination process. To alleviate the charge recombination, an effective strategy is to employ reduced graphene oxide (RGO) as a charge sink, separator and transporter. Gel combustion method has been adopted to prepare LFO nano sphere and through ultrasonication LFO spheres was fabricated on RGO surface. The synthesized nano structured materials are characterized by powder X-ray diffraction( PXD), UV-vis diffuse reflectance spectra (UV-vis DRS), transmission electron microscopy (TEM/HRTEM), X-ray photoelectron spectroscopy (XPS) and photoluminescence (PL) spectroscopy. UV-vis DRS data revealed that the nanocomposites are visible light absorbing semiconductors with band gap ranging from similar to 2.1-1.96 eV. When tested the photocatalyst towards hydrogen production under visible light, the rate of GLFO increases more than two fold than neat LFO. So as a case study, the GLFO photocatalyst can contribute a remarkable outcome in the photocatalytic field. Formation mechanism, structural, optical and electronic properties of LaFeO3 nanosphere/RGO composite is discussed and correlated with photocatalyic activity. (C) 2017 Elsevier B.V. All rights reserved.