Pt@WS2 Mott-Schottky Heterojunction Boosts Light-Driven Active Ion Transport for Enhanced Ionic Power Harvesting

Bioinspired light-driven ion transport in two-dimensional (2D) nanofluidics offers exciting prospects for solar energy harvesting. Current single-component nanofluidic membranes often suffer from low light-induced driving forces due to the easy recombination of photogenerated electron-hole pairs. Herein, we present a Pt@WS2 Mott-Schottky heterojunction-based 2D nanofluidic membrane for boosting light-driven active ion transport and solar enhanced ionic power harvesting. The photovoltaic effect in the Mott-Schottky heterojunctions and photoconductance effect in WS2 multilayers account for more efficient charge separation across the nanofluidic membrane. In an equilibrium electrolyte solution, we observe directional cationic transport from the WS2 to the Pt region under visible-light illumination. In 10-3 M KCl electrolyte, the photocurrent and photovoltage reach 11.84 μA cm-2 and 30.67 mV, respectively. Moreover, the output power can reach up to 5.02 W m-2 under light illumination, compared to a value of 2.56 W m-2 without irradiation. This work not only introduces a driving mechanism for boosting ion transport but also offers a pathway for integrating multiple energy sources. © 2024 American Chemical Society.