Visible-light-driven photoelectrochemical and photocatalytic performance of NaNbO₃/Ag₂S core-shell heterostructures

Abstract

Herein, we report the fabrication of visible-light-active NaNbO₃/Ag₂S staggered-gap core–shell semiconductor heterostructures with excellent photoelectrochemical activity toward water splitting, and the degradation of a model pollutant (methylene blue) was also monitored. The heterostructures show a pronounced photocurrent density of approximately 2.44 mA cm⁻² at 0.9 V versus Ag/AgCl in 0.5 m Na₂SO₄ and exhibit a positive shift in onset potential by approximately 1.1 V. The high photoactivity is attributed to the efficient photoinduced interfacial charge transfer (IFCT). The core–shell design alleviates the challenges associated with the electron–hole paths across semiconductor junctions and at the electrolyte–semiconductor interface. These properties demonstrate that NaNbO₃/Ag₂S core–shell heterostructures show promising visible-light photoactivity and are also efficient, stable, and recyclable photocatalysts.