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 TiO 2 nanorod arrays (TiO 2 ), which were decorated with AgVO 3 quantum dots (QDs) on and a layer of V 2 O 5 film, forming a heterojunction material for removal pollutants and photoelectrochemical (PEC) water splitting. The AgVO 3 /V 2 O 5 -TiO 2 nanorod arrays (AgVO 3 /V 2 O 5 -TiO 2 ) 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 TiO 2 modified with AgVO 3 and V 2 O 5 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 TiO 2 . The resulting photocurrent density (116 uA/cm 2 ) and photodegradation efficiency (rate constant, k = 0.025 min −1 ) of AgVO 3 /V 2 O 5 -TiO 2 are approximately 20 (6 uA/cm 2 ) and 5 times (0.005 min −1 ) higher than those of bare TiO 2 , respectively. The AgVO 3 /V 2 O 5 -TiO 2 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 TiO 2 interface by AgVO 3 and V 2 O 5 could promote the separation and transport of charge carriers.