Short-Time Hydrothermal Synthesis of CuBi(2)O(4) Nanocolumn Arrays for Efficient Visible-Light Photocatalysis

In this article, a short-time hydrothermal method is developed to prepare CuBi(2)O(4) nanocolumn arrays. By using Bi(NO(3))(3)·5H(2)O in acetic acid and Cu(NO(3))(2)·3H(2)O in ethanol as precursor solutions, tetragonal CuBi(2)O(4) with good visible light absorption can be fabricated within 0.5 h at 120 °C. Tetragonal structured CuBi(2)O(4) can be formed after 15 min hydrothermal treatment, however it possesses poor visible light absorption and low photocatalytic activity. Extending the hydrothermal treatment duration to 0.5 h results in a significant improvement invisible light absorption of the tetragonal CuBi(2)O(4). The CuBi(2)O(4) obtained through 0.5 h hydrothermal synthesis shows a band gap of 1.75 eV and exhibits the highest photocatalytic performance among the CuBi(2)O(4) prepared with various hydrothermal time. The removal rate of methylene blue by the 0.5 h CuBi(2)O(4) reaches 91% under visible light irradiation for 0.5 h. This study proposes a novel strategy to prepare photoactive CuBi(2)O(4) nanocolumn arrays within 0.5 h at a moderate temperature of 120 °C. The hydrothermal method provides a facile strategy for the fast synthesis of metal-oxide-based photocatalysts at mild reaction conditions.