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.