Mechanochemical synthesis of self-circulating Z-scheme AgCl/SiC photocatalyst from retired PV silicon: pH stability, reusability and broad applicability

• Published in: Applied surface science 2024-11, Vol.672, p.160733, Article 160733
• Main Authors: Chen, Yunyan, Teng, Chengyao, Li, Fei, Tang, Zhijie, Xu, Lijun, Zhang, Li, Huang, Qing, Zhu, Jianming, Yuan, Wenyi
• Format: Article
• Language: English
• Subjects: Broad applicability; Mechanochemical ball milling; Retired PV silicon; Self-circulating system; Z-Scheme heterojunction
• ISSN: 0169-4332
• DOI: 10.1016/j.apsusc.2024.160733

[Display omitted] •The retired PV silicon was used to synthesize the ACS photocatalyst.•The self-circulating system was consist of Ag+-Ag0 and Cl--Cl0 conversions.•ACS exhibit high photocatalytic activity over degrading various PPCPs and dyes.•Ball milled ACS exhibited excellent long-term circulation and pH stability.•Ball milling increased h+ and e- activity, enhancing photocatalytic activity of ACS. Recycling and reusing valuable components of retired photovoltaic (PV) panels, such as crystalline silicon, has become a topic of interest due to the large number of panels are being decommissioned. This study focused on creating a self-circulating Z-scheme AgCl/SiC (ACS) photocatalyst using retiredPV silicon as raw material through a mechanochemical process. The mechanochemical ball milling addressed the issue of unstable photocatalytic performance of AgCl caused by photocorrosion by facilitating rapid interconversion between Ag+ and Ag0, enhancing the pH stability, reusability and photocatalytic activity of ACS. ACS was demonstrated to have significant photocatalytic capabilities in breaking down pharmaceutical and personal care products (PPCPs) and dye pollutants, achieving complete degradation of PPCPs in 30 min under visible light and over 80% degradation of dyes within the same timeframe. Furthermore, ACS maintained a 99% degradation rate across a pH range of 2 to 10 and sustained a 90% degradation rate after 10 cycles. The results of toxicity analysis indicated that the toxicant of intermediates were decreased gradually and can be controlled in a safe range. The pH stability and broad applicability of ACS make it well-suited for diverse environmental conditions. This ACS photocatalyst represents a promising approach to addressing the issue of photocorrosion in AgCl, and recycling of crystalline silicon from retired PV panels.