Preparation of Bifunctional CuWO 4 ‐Based Heterostructure Nanocomposites for Noble‐Metal‐Free Photocatalysts

Abstract This article describes the preparation of copper tungstate ( )‐based heterostructured nanocomposites by facile two‐step polyol assisted hydrothermal‐annealed process. A series of characterization techniques (FESEM, EDS, HRTEM, XPS, XRD and FTIR etc.) were confirmed the formation of type‐I ) and type‐II heterojunction as function of pH and annealing temperatures. Also , , , and CuO were found as secondary phases with . These nanocomposites exhibited the enhanced visible light absorption and the band gap ( ca . 1.7 eV) of is smaller than the early reported value (2.1‐2.3 eV). In photocatalytic degradation, the / and were showed 1.66 fold times higher and nearly equal apparent rate constant respectively than that of . In photoelectrochemical (PEC) studies, the , / , and nanocomposites showed more photocurrent density of 3.5, 2.2, 0.71 and 0.41 mA/cm 2 at 1.23 V RHE respectively than CuWO 4 . The existence of dual co‐catalysts (Cu 2 O and CuO) with CuWO 4 , strongly promote the electron‐hole pair separation and migration. Among the nanocomposite, the was showed the similar static photocurrent as that of under 1 Sun illumination. The advantage of present work is noble‐metal‐free photocatalysts prepared with binder free, less time, low energy consumption and cost, and environmental benign.