MXene derived Ti 3 C 2 /TiO 2 /Ag persistent photocatalyst with enhanced electron storage capacity for round-the-clock degradation of organic pollutant

• Published in: Journal of colloid and interface science 2024-02, Vol.656, p.233
• Main Authors: Fu, Xijun, Kong, Yajing, Wang, Minjie, Cai, Tao, Zeng, Qingyi
• Format: Article
• Language: English
• ISSN: 1095-7103

Persistent photocatalysis has garnered significant attention due to its ability to sustain catalytic activity in dark by storing electrons. However, the practical application of persistent photocatalysis is hindered by limited electron storage capacity. Herein, we synthesized and demonstrated that Ti C /TiO /Ag persistent photocatalyst has good electron storage capability. The electron storage capacity of Ti C /TiO /Ag is up to 0.125 μmol/mg, which is 2.5 times that of Ti C /TiO . The enhanced electron storage capacity resulted in improved dark-reaction activity because more electrons react with oxygen to form more radicals, as evidenced by degradation experiments of various organics. Especially, persistent photocatalytic degradation of tetracycline hydrochloride by Ti C /TiO /Ag was achieved under natural outdoor conditions (from 2:00p.m. to 8:00p.m.). Additionally, the aid of oxidants such as peroxymonosulfate (PMS) can further improve the dark-reaction activity. TiO /Ti C /Ag/PMS system exhibits excellent efficacy in removing tetracycline hydrochloride, oxytetracycline, rhodamine b, methyl orange, and methylene blue, with removal rates reaching 79.5 %, 81.4 %, 98.9 %, 99.1 %, and 99.2 %, respectively (15 min of light-reaction and 45 min of dark-reaction). This work provides a new strategy to enhance electron storage capacity and demonstrates that decoupling of light-reaction and dark-reaction may provide a new opportunity for photocatalytic removal of pollutants around the clock.