Heteroatoms-doped carbon materials have recently emerged as effective catalysts for various chemical and electrochemical reactions. The free of metals especially noble metals reduces cost and eliminates issues like sintering or leaching of metals at elevated temperatures in solvents. In this work, selective hydrodeoxygenation (HDO) of 5-hydroxymethylfurfural (HMF) to 2,5-dimethylfuran (DMF) is for the first time achieved over simple nitrogen-doped carbon (N-C) catalysts. At optimal reaction conditions, a 91% yield of DMF is obtained with excellent catalyst stability. Extensive characterization, including extended X-ray absorption fine-structure (EXAFS) and soft X-ray absorption spectroscopy (sXAS), model reactions, basic data science analysis, and DFT calculations suggest that ppm of Fe in particular FeN 3 sites formed in pyrolysis, rather than non-metallic elements, drive key steps such as H 2 activation and deoxygenation of –OH during HMF HDO.
Wangchuan Zhu,Chuantao Wang,Xiang Li,Wenhui Shi,Qiyu Chen,Xinlei Bai,Feng Fu,Danjun Wang,Chunming Yang
Advanced oxidation processes based on piezo-promoted peroxymonosulfate (PMS) activation in environmental remediation have been widely applied, but the treatment efficiency of pollutants was restricted by sluggish charge separation and low affinity of PMS. Herein, trace iron-doped layered molybdenum disulfide (Fe/MoS 2 ) was used to degrade pollutants by piezo-promoted PMS activation. Real-time reaction site changes in carbamazepine (CBZ) degradation process were predicted by Fukui function calculation of the reaction intermediates, and the possible degradation pathways were given. Through piezoresponse force microscopy and calculation of the adsorption energy, electronic localized functions and Crystal Orbital Hamilton Population, it was verified that Fe doping improves the adsorption of oxygen-containing reactants on MoS 2 , enhancing the electron delocalization and piezo-polarization field, thus accelerating the piezo-promoted PMS activation kinetics. The degradation efficiency of CBZ on Fe/MoS 2 (0.44 min −1 ) was about 22 times than that of MoS 2 . Piezo-promoted PMS activation strategy based on Fe/MoS 2 still maintains a high removal rate in the treatment of dye and antibiotic pollutants such as ornidazole, rhodamine B, tetracycline, methyl orange, chlortetracycline. This study provides insights into the mechanism by which piezo-promoted PMS activation, and achieving high chemical efficiency for pollutants removal.