The role of single-atom La in the PDS system: Key hydrogen bonding and electron transport effects

[Display omitted] •The novel La single-atom catalysts were prepared for activation of PDS.•La + PDS systems had degraded more than 95 % TCs within 30 mins.•La played as the “electrons bridge” for accelerating the electrons transfer.•Hydrogen-bond enriched the adsorption of La-N-C and PDS.•Electrons of La‘s d orbital induced into more1O2. Current single-atom studies in the perdisulfate (PDS) system were focused on transition metals, but researching La-series metals might provide new insights for the efficient utilization of this system. The original structure’s Zn was evaporated at high temperatures, thereby we utilized Zeolitic Imidazolate Frameworks (ZIFs) as a substrate to synthesize a type of La-SACs catalysts. The La single atom in this work was identified to the La-N4 configuration through La-L3 X-ray edge absorption spectroscopy. Experimental observations in suspension demonstrated that the PDS activation capability of La is on par with, if not superior to, that of transition metals such as Co and Cu. Tetracyclines (10 mg L-1) were eliminated within 30 min via La-N-C + PDS systems and the pseudo-first-order was higher than 0.0929 min-1. The Hydrogen bond between PDS and La-N-C and active electron of d orbital in La atoms had the significant influence on the generation of ROS (1O2 and •OH). Furthermore, the excellent electron transfer of La-N-C also promoted the activation rate of PDS. The findings of this study indicated that La could play a crucial part in PDS catalyst for degradation of organic pollutes in aquatic environment, providing the new method for exploration of single atom materials in PDS systems.