Fabrication of a stable light-activated and p/n type AgVO3/V2O5-TiO2 heterojunction for pollutants removal and photoelectrochemical water splitting

In this study, we fabricated TiO2 nanorod arrays (TiO2), which were decorated with AgVO3 quantum dots (QDs) on and a layer of V2O5 film, forming a heterojunction material for removal pollutants and photoelectrochemical (PEC) water splitting. The AgVO3/V2O5-TiO2 nanorod arrays (AgVO3/V2O5-TiO2) synthesized by the secondary hydrothermal method were grown on conductive glass to form one-dimensional (1D) nanorod and p-n junction structures. Through experimental characterisation and testing, optical, morphological photocatalysis and PEC characteristics of the materials were measured and studied. The TiO2 modified with AgVO3 and V2O5 can significantly improve the visible light optical absorption, the reduce the electron-hole pair binding rate and shorten the band gap (3.07–1.41 eV) of TiO2. The resulting photocurrent density (116 uA/cm2) and photodegradation efficiency (rate constant, k = 0.025 min−1) of AgVO3/V2O5-TiO2 are approximately 20 (6 uA/cm2) and 5 times (0.005 min−1) higher than those of bare TiO2, respectively. The AgVO3/V2O5-TiO2 achieved a current density of 10 mA at an overpotential of 246.2 mV and exhibited excellent oxygen evolution reaction (OER) performance. The systematic PEC experiments concluded that the optimized of the TiO2 interface by AgVO3 and V2O5 could promote the separation and transport of charge carriers.