This study is focused on the photoreduction of CO2 into CH4 using CaxTiyO3 perovskite nanoparticles. CaxTiyO3 nanoparticles were successfully synthesized by a hydrothermal method. The structure and property of CaxTiyO3 were characterized using XRD, UV-vis, PL, and BET techniques. The photoreduction of CO2 was performed with UV-lamp (6 W cm(-2)) irradiation. The gas products were analyzed in a gas chromatograph equipped with FID and TCD detectors. The methane formation rate from CO2 and H2O was 17 mu mol/ g for 7 h using 0.2 g of Ca1.00Ti1.00O3. (C) 2015 Elsevier B.V. All rights reserved.