A novel photocatalyst, Y2SiO5:Pr3+,Li/Pt-NaNbxTa1-xO3, for highly efficient photocatalytic hydrogen evolution under visible-light irradiation

摘要

In this work, Y2SiO5:Pr3+,Li, as an excellent up-conversion luminescence agent from visible-light to ultraviolet-light, is synthesized by using sol-gel method. And then, a series of Y2SiO5:Pr3+,Li/NaNbxTa1-xO3 (x = 0.00, 0.25 and 0.50) with different amounts of Y2SiO5:Pr3+,Li are prepared by using hydrothermal method. The prepared samples are characterized by X-ray diffractometer (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), UV-vis absorption spectroscopy and photoluminescence spectroscopy (PL). The activities of Y2SiO5:Pr3+,Li/Pt-NaNbxTa1-xO3 are investigated through photocatalytic hydrogen evolution in 10 vol% methanol solution under visible-light irradiation. The influences of Nb content in NaNbxTa1-xO3, mass ratio of Y2SiO5:Pr3+,Li and NaNb0.5Ta0.5O3, visible-light irradiation time and reuse-times are examined on the visible-light photocatalytic hydrogen evolution, The experimental results showed that the prepared Y2SiO5:Pr3+,Li/Pt-NaNb0.5Ta0.5O3 with 0.4:1.0 mass ratio of Y2SiO5:Pr3+,Li and NaNb0.5Ta0.5O3 and 0.25 wt% Pt loading displayed a highest evolved hydrogen activity under visible-light irradiation. This study may provide some significant references for large scale photocatalytic hydrogen evolution utilizing solar energy. (C) 2018 Elsevier B.V. All rights reserved.