演讲嘉宾

Dr. Tao Zeng, Professor

College of Environment, Zhejiang University of Technology, Hangzhou, China

Biography: Dr. Tao Zeng is a Professor at Zhejiang University of Technology in China. He obtained his Ph.D. in Environmental Science from the Research Center for Eco-Environmental Sciences at the Chinese Academy of Sciences in 2015. Subsequently, he pursued a postdoctoral research position at Hong Kong Baptist University in 2018. Professor Zeng's research is primarily focused on environmental nanotechnology, advanced water purification technologies, and the treatment of emerging contaminants. He has published over 50 peer-reviewed papers in renowned journals such as Environmental Science & Technology, Applied Catalysis B: Environmental, and Chemical Communications, among others, garnered over 2300 citations. He was honored with the Distinguished Young Scholar award by the Natural Science Foundation of Zhejiang Province in 2021.

Topic: Oxyanion Activation for the Removal of Emerging Contaminants

Abstract: Precisely tailoring the electronic structure and surface chemistry of metal-free covalent triazine frameworks (CTFs) for efficient photoactivation of oxyanions is environmentally desirable but still challenging. Of interest to us in this work was to construct artificial defective accumulation sites into a CTF network (CTF-SDx) to synchronously modulate both thermodynamic (e.g., band structure) and kinetic (e.g., charge separation/transfer/utilization and surface adsorption) behaviors and probe how the transformation affected the subsequent activation mechanism of peroxymonosulfate (PMS). With incorporation of terminal cyano (-CN) groups and boron (B) dopants, the delocalized CTF-SD underwent a narrowed electronic energy gap for increased optical absorption as well as a downshifted valence band position for enhanced oxidation capacity. Moreover, the localized charge accumulation regions induced by the electron-withdrawing -CN groups facilitated the exciton dissociation process, while the adjacent electron-deficient areas enabled strong affinity toward PMS molecules. All these merits impelled the photoactivation reaction with PMS, and a 15-fold enhancement of bisphenol-A (BPA) removal was found in the CTF-SD2/PMS/vis/system compared with the corresponding pristine CTF system. Mechanistic investigations demonstrated that this system decomposed organics primarily through a singlet oxygen-mediated nonradical process, which originated from PMS oxidative activation over photoinduced holes initiated by an electron transfer process, thereby opening a new avenue for designing an efficient PMS activation strategy for the selective oxidation of organic pollutants.