Laplace pressure assisted hydrovoltaic effect in-situ enhancing photocatalytic water splitting

Abstract

The generated output voltage resulting from the hydrovoltaic effect serves to directly suppress catalyst carrier recombination, thereby enhancing the process of photocatalytic water splitting. The principal challenge lies in establishing a seamless pathway for water that facilitates the synergistic interplay of the hydrovoltaic and photocatalytic effects. Laplace pressure, generating from a specific surface pattern, emerges as a compelling force capable of aiding the autonomous transport of water. Consequently, it enables the harmonious collaboration of hydrovoltaic and photocatalytic effects. In this article, a pioneering surface pattern comprised of TiO2 (P25), characterized by a Laplace pressure differences, engenders a self-sustaining conduit for water transport, thereby instigating an enhanced hydrovoltaic effect. This, in turn, enhances the photocatalytic water splitting capability of P25. The resulting system is denoted as hydrovoltaic-effect-enhanced photocatalytic P25 (HP–P25). Notably, the hydrovoltaic effect voltage of P25 attains a new high at 5.5 V. Furthermore, this voltage facilitates the in-situ suppression of catalyst carrier recombination, leading to a 6.6-fold enhancement in the efficiency of photocatalytic water splitting. The demonstrated system thus introduces a novel and uncomplicated paradigm for the collaborative manifestation of hydrovoltaic and photocatalytic effects.