Facile methodology to generate Cu2O/TiO2 heterojunction on FTO electrode for photoelectroreduction of nitrate

Abstract

Easy and low-cost synthesis of a Cu2O/TiO2/FTO electrode is proposed. The Cu2O/TiO2 heterojunction was synthesized by sintering TiO2 nanoparticles on an FTO electrode surface, followed by a Cu2O electrochemical deposition step. Characterization of the electrode was performed by FE-SEM-EDX microscopy, Raman and UV–Vis DR spectroscopy, and electrochemical methods. The photoelectrochemical behavior was characterized, and the p-type character material was confirmed. The reduction of nitrate to nitrite was performed using the Cu2O/TiO2/FTO electrode under Xe lamp illumination with lower overpotentials than those commonly used in this electrochemical process. Nitrate/nitrite conversion was achieved with a promising result of about 22% conversion at ?0.05 V RHE.