Electron transportation path build for superior photoelectrochemical performance of Ag3PO4/TiO2

Abstract

TiO2 is an attractive photoanode material with its large band gap, whilst its performance largely suffers from low efficiency on both charge separation and solar conversion. Herein, a self-organized TiO2 nanotube arrays (TNT) is prepared by anodized Ti foil in ethylene glycol electrolyte to ameliorate charge transmission ability. Ag3PO4 is further synthesized on TNT substrate by dipping method. HRTEM images results indicate Ag3PO4 nanoparticles are successfully deposited on the surfaces of TNT. Photoelectrochemical tests show the Ag3PO4/TiO2 heterojunction has a higher photocurrent density of 2.34 mA cm-2 at 0 V than that of pure TNT (0.38 mA cm-2). This is attributed to an Ag "pump" reduced on the interface of Ag3PO4/TiO2, therefore electron transportation path is built between Ag3PO4 and TiO2 leading to photogenerated electrons and holes effective separation. This high photocurrent density array films facilitates it a desirable photoelectrochemical material for water splitting.