A novel Z-scheme Er3+:YAlO3/Ta2O5-CaIn2S4/MoSe2-reduced graphene oxide photocatalyst with superior photocatalytic hydrogen evolution activity

Abstract

Here, a high effective visible-ultraviolet up-conversion luminescence agent (Er3+:YAlO3) was synthesized and the Er3+:YAlO3/Ta2O5 composite was prepared by sol-gel method. The MoSe2-reduced graphene oxide (MoSe2-RGO) hybrid as co-catalyst was prepared by hydrothermal method. Afterwards, a new Z-scheme photocatalyst, Er3+:YAlO3/Ta2O5-CaIn2S4/MoSe2-RGO, was successfully assembled by hydrothermal methods for visible-light photocatalytic hydrogen evolution. The Er3+:YAlO3, MoSe2-RGO, Er3+:YAlO3/Ta2O5, CaIn2S4/MoSe2-RGO, Er3+:YAlO3/Ta2O5/MoSe2-RGO and Er3+:YAlO3/Ta2O5-CaIn2S4/MoSe2-RGO were all characterized by X-ray diffractometer (XRD), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), Energy dispersive spectrometer (EDS), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). The UV–vis absorption spectra and photoluminescence (PL) spectra of Er3+:YAlO3 were also measured. The photocatalytic hydrogen production activity of Er3+:YAlO3/Ta2O5-CaIn2S4/MoSe2-RGO was examined under visible-light irradiation. In addition, the reused times of Er3+:YAlO3/Ta2O5-CaIn2S4/MoSe2-RGO for photocatalytic hydrogen production were investigated. The results showed that the Er3+:YAlO3/Ta2O5-CaIn2S4/MoSe2-RGO photocatalyst in aqueous methanol solution displayed the highest photocatalytic hydrogen production activity under visible-light irradiation and after five-times photocatalytic hydrogen experiment the photocatalytic activity of Er3+:YAlO3/Ta2O5-CaIn2S4/MoSe2-RGO is basicly stable in the process of splitting methanol aqueous solutions.