Non-binder synthesis of g-C3N4 decorated on TiO2 nanotube arrays toward photo/electrochemical water splitting

Abstract

Photoelectrodes based TiO₂ materials are widely used for photoelectrochemical water splitting because of their low cost, abundance, stability, nontoxicity, and appropriate energy potential. Titanium nanotube arrays (TNAs) and graphitic carbon nitride (gCN) were combined to create a water splitting photoelectrode that enhances solar energy spectrum utilization and facilitates carrier transport. In this study, the PEC electrodes based on gCN/TNAs were fabricated by dip coating of gCN solution on the TNAs electrodes from the acidic exfoliation method of bulk g-C₃N₄. When an appropriate concentration of gCN (0.10 g L⁻¹) is applied, it demonstrates favorable performance for HER with an overpotential of 0.9 V at a current density of 10 mA cm⁻². The 0.10 gCN/TNAs-5 sample showed a photo-transient current density about 2.1 times higher than the TNAs-5 sample. These results demonstrate that the non-binder photoelectrode gCN/TNAs, produced through simple fabrication techniques, has promise for hydrogen production.