Xiaoqing Shu, Cheng Zhao, Xu Zhang, Xudong Liu, Zhiqiang Xing, Dawei Fang, Jun Wang

College of Chemistry, Liaoning University

Youtao Song,

College of Environment

Abstract

Here, an effective infrared-ultraviolet up-conversion luminescence agent (β-Tm³⁺, Yb³⁺: NaYF₄) is synthesized by hydrothermal method and the corresponding photocatalyst (β- Tm³⁺, Yb³⁺: NaYF⁴/MoS₂-Ta₂O₅) is successfully prepared. The compositions and morphologies of the prepared β-Tm³⁺, Yb³⁺: NaYF₄, MoS₂-Ta₂O₅ and β-Tm³⁺, Yb³⁺: NaYF₄/ MoS₂-Ta₂O₅ are all characterized by XRD, SEM, EDX and FT-IR techniques. The photocatalytic activity of β-Tm³⁺, Yb³⁺: NaYF₄/ MoS₂-Ta₂O₅ is examined through photocatalytic hydrogen evolution from methanol aqueous solution under near-infrared light irradiation. In addition, some influence factors such as β-Tm³⁺, Yb³⁺: NaYF₄ and MoS₂-Ta₂O₅ mass ratio, heat-treated temperature and initial

solution pH value on the photocatalytic hydrogen evolution activity of β-Tm³⁺, Yb³⁺: NaYF₄/ MoS₂-Ta₂O₅ are also studied. The results show that the photocatalytic hydrogen evolution activity of Ta₂O₅ can be greatly enhanced by adding up-conversion luminescence agent (β-Tm³⁺, Yb³⁺: NaYF₄) and co-catalyst (MoS₂). And, the β-Tm³⁺, Yb³⁺: NaYF₄ MoS₂-Ta₂O₅catalyst with 40:100 mass ratio heat-treated at 450 °C for 60 min in aqueous methanol solution at initial pH = 6.0 displays the highest photocatalytic activity under near-infrared light irradiation.

Read the full article here:   69-Highly efficient near-infrared light photocatalytic hydrogen evolution over MoS2 supported Ta2O5 combined with an up-conversion luminescence agent (beta-Tm3+,Yb3+NaYF4MoS2-Ta2O5 nanocomposite).pdf