Photocatalytic water splitting properties of Cu2+ exchanged Beta zeolites

Abstract

Photocatalytic water splitting with solar energy is the most promising and environmentally friendly hydrogen production method. Having an efficient and cost-effective photocatalyst is key to hydrogen production. Cu dopant has been shown to greatly enhance photocatalytic activities. In this work, Cu2+ ions were doped into Beta zeolite powders (Cu–Beta) by the ion exchange method. The hydrogen evolution efficiency of Cu–Beta was much higher than the raw Beta zeolites without Cu loading. After solid phase reaction, the band gap of Cu–Beta reduced from 3.48 eV to less than 2 eV, and as a result enhanced the optical absorption intensity, particularly in the visible region. The best hydrogen evolution efficiency was 102.12 μmol · g−1 · h−1 when the treated temperature was 900 °C (Cu–Beta–900). The temperature of the solid phase reaction had an important influence on the photocatalytic performance of Cu–Beta; a suitable reaction temperature can greatly improve its photocatalytic performance.