Robust photoelectrocatalytic degradation of antibiotics by organic-inorganic PDISA/Bi2WO6 S-scheme heterojunction membrane

Abstract

Ensuring the stability of the photoelectrode is paramount for optimal photoelectrocatalysis performance. In this investigation, a hybrid nanofiber film, incorporating the π-π conjugated self-assembly of perylene diimide monomers (PDISA) with Bi2WO6 (PDISA/Bi2WO6), was fabricated through the electrospinning process. Subsequently, this flexible electrospun film was pressed onto a Ni mesh to create a robust PDISA/Bi2WO6 electrode membrane. Results from photoelectrocatalytic studies reveal that the devised PDISA/Bi2WO6 photoanode significantly enhances the photoelectrocatalytic degradation efficiency of tetracycline (TC) and ciprofloxacin (CIP). Specifically, the apparent rate constants for the photoelectrocatalytic degradation of TC by 30%PDISA/Bi2WO6, compared to pristine PDISA and Bi2WO6, are elevated by 1.9 and 2.0 times, respectively. Moreover, the reaction rates of the photoelectrocatalytic (PEC) process surpass those of photocatalysis (PC) and electrocatalysis (EC) by 1.9 times and 8.0 times, respectively. Impressively, even after five cycles of PEC degradation of TC, the photoelectrode maintains 98.4% of its initial degradation rate, indicating its exceptional stability. These improvements in degradation efficiency and stability are attributed to the creation of the PDISA/Bi2WO6 S-scheme heterojunction membrane photoanode and the synergistic effects of photoelectrocatalysis.