Facile synthesis of interlocking g-C3N4/CdS photoanode for stable photoelectrochemical hydrogen production

Abstract

A simple and facile two-step method, including electrophoretic deposition and chemical bath deposition strategies, has been used to fabricate a novel interlocking g-C3N4/CdS photoanode on conductive substrate. Integrating a large area of intercontact g-C3N4/CdS heterojunction with an intimate connection between the photocatalysts and the substrate, the separation and migration of the photogenerated carriers by g-C3N4 and CdS are significantly improved, and the internal resistance of the photoanode is effectively reduced. The optimal g-C3N4/CdS photoanode exhibits an excellent visible light photocurrent density of 5.4 mA cm-2 at 0.0 V bias (vs. Ag/AgCl) and the photoelectrochemical H2 production rate reaches 81.1 μmol h-1 cm-2. Moreover, the stability of this interlocking g-C3N4/CdS photoanode not only reflects in a 9-hour long time recycling photoelectrochemical H2 production test, but also in an outstanding steady structure which even be stabilized in an ultrasonic treatment. The present study provides a practical and convenient technique to develop such an earth abound and low-cost CdS/C3N4 photoanode which can be used for high efficiency and stable photoelectrochemical solar energy conversion.