Redeeming the photocatalytic potential of CuWO4 incorporating Ag6Si2O7 via S-scheme PN heterostructure

Abstract

Water pollution and energy crisis are deemed the most prevalent issues of contemporary decades, and enhanced efforts to counteract these issues via semiconductor photocatalyst engineering are among the best-proposed solutions. Semiconductor photocatalysts could effectively transform clean sunlight into chemical energy, thereby facilitating the breakdown of organic dyes. Herein, we demonstrate the PN heterojunction S scheme photocatalyst Ag6Si2O7/CuWO4 via the facile hydrothermal method. The Ag6Si2O7/CuWO4 heterostructure discerns the broadening of the absorption spectrum and enhanced carrier separation owing to the interfacial process at the interface. Both these aspects work as a stimulus regarding the photocatalytic properties and add versatilities to the effective utilization of carriers. The performance of different ratios of Ag6Si2O7 and CuWO4 in Ag6Si2O7/CuWO4 composite was monitored via photocatalytic degradation of Rhodamine B and Methylene Blue under visible irradiation. About 97.50% degradation efficiency for RhB was reached in 50 minutes at a 1:5 molar ratio (AgCW-E). The degradation constant rate of AgCW-E for RhB and MB was 21.12 and 26.13 times higher than pristine, respectively. Based on trapping experiments and electron spin resonance spectra, it was determined that the photogenerated holes (h+) and •O2- played a crucial role as active species in the photocatalytic degradation of RhB. The synthetic substances additionally demonstrated great promise for recycling. The present study delivers an innovative perspective on developing a more potent Ag6Si2O7/ CuWO4 nano heterojunction photocatalyst that can capture visible light.