Flower-like CdS/CdV2O6 composite for visible-light photoconversion of CO2 into CH4

Flower-like CdS/CdV2O6 composite has been used in the present work for the visible-light (lambda >= 420 nm) photoconversion of CO2 into CH4. CdV2O6 has been synthesized by simple hydrothermal method. Limited chemical conversion route (LCCR) has been used for the synthesis of novel efficient visible light driven CdS/CdV2O6 composite. Several characterization techniques such as X-ray diffraction (XRD), high resolution electron microscopy (HRTEM), scanning electron microscopy (SEM), UV/visible spectroscopy, X-ray photoelectron spectroscopy (XPS) and Brunauer-Emmett-Teller (BET) have been used to characterize the as synthesized photocatalysts. XRD confirms the formation of monoclinic structure of CdV2O6 and orthorhombic phase of CdS in the nanocomposite. HRTEM and SEM results reveal rod-like morphology of CdV2O6 while CdS/CdV2O6 is in the form of well-shaped bunches of flower-like structures. XPS is used to determine the alignment of energy levels against the standard hydrogen electrode (SHE). The as-synthesized flower-like composites have then been employed as efficient photocatalysts for visible-light photoconversion of CO2 into CH4. The CdS/CdV2O6 composite results in visibly higher yield of methane than that of single semiconductors that might be attributed to the suppressed recombination of the photogenerated charge carriers. Flower-like CdS/CdV2O6 composite also exhibits tremendous photostability than the individual counterparts. (C) 2016 Elsevier Ltd. All rights reserved.