Transition metal induced interfacial d-p orbital hybridization boosting biochar for efficient fenton-like decontamination

Transition metals (TMs) are widely employed to improve poor intrinsic activity of biochar for peroxymonosulfate (PMS) activation towards water purification. However, the mechanistic effects of TMs on carbon substrates requires further understanding. Herein, we constructed TM-modified C-Ni and C-Ni-Co catalysts via simple pyrolysis of rice husk precursor, optimizing carbonaceous morphologic and electronic structures. The Co-Ni-Co (0.013 min −1 ) exhibited over 10 times higher performance than pristine biochar for iohexol (IOH) removal. Systemic spectroscopic and electrochemical measurements indicate that embedded Ni increases graphitization degree facilitating IOH adsorption by π-π conjugated attraction. And, the anchored Co enhances work function promoting electron extraction for selective generation of 1 O 2 . The interfacial d-p orbital hybridization increases the acidic degree on biochar for PMS adsorption, accelerating electron exchange for PMS activation. Our work attempts to study the complex interaction between carbon and metal sites by orbital hybridization to design efficient PMS activators for Fenton-like decontamination.