A scalable strategy for the convenient and rapid preparation of nitrogen-doped carbon-coated iron-based alloy catalysts was developed.By controlling the type and amount of metal salts in the precursor,various types of...A scalable strategy for the convenient and rapid preparation of nitrogen-doped carbon-coated iron-based alloy catalysts was developed.By controlling the type and amount of metal salts in the precursor,various types of nitrogen-doped carbon-coated alloy catalysts can be prepared in a targeted manner.Fe_(2)Ni2@CN materials with small particle sizes and relatively homogeneous basic sites showed promising results in the N-alkylation reaction of benzyl alcohol with aniline(optimum yield:99%).It is worth noting that the catalyst can also be magnetically separated and recovered after the reaction,and its performance can be regenerated through simple calcination.Furthermore,it was confirmed by kinetic experiments that the activation of C–H at the benzyl alcohol benzylic position is the rate-determining step(RDS).According to density flooding theory calculations,Fe_(2)Ni2@CN catalysts require less energy than other materials(Fe@CN and Ni@CN)for the RDS(dehydrogenation reaction)process.Therefore N-alkylation reactions are more easily carried out on Fe_(2)Ni2@CN catalysts,which may be the reason for the best catalytic activity of Fe-Ni alloy materials.These carbon-coated alloy materials will show great potential in more types of heterogeneous catalysis.展开更多
Chlorinated organic pollutants(COPs)have caused serious contaminants in soil and groundwater,hence developing methods to remove these pollutants is necessary and urgent.By a simple hydrothermal method,we synthesized t...Chlorinated organic pollutants(COPs)have caused serious contaminants in soil and groundwater,hence developing methods to remove these pollutants is necessary and urgent.By a simple hydrothermal method,we synthesized the bimetallic iron-nickel sulfide(FeNiS)particles which exhibited excellent catalytic property of COPs removal.FeNiS was chosen as the peroxydisulfate(PDS)activator to removal COPs including 4-chlorophenol(4-CP),1,4-dichlorophenol(1,4-DCP)and 2,4,6-trichlorophenol(2,4,6-TCP).The results show that FeNiS can efficiently activate PDS to produce sulfate radical(SO4·-)which plays major role in the oxidative dechlorination and degradation due to its strong oxidizing property and the ability of producing hydroxyl radicals(·OH)in the alkaline condition.Meanwhile,the Cl-abscised from COPs during the dechlorination can turn into the chlorine radicals and enhance the degradation and cause further mineralization of intermediate products.This bimetallic FeNiS catalyst is a promising PDS activator for removal of chlorinated organics.展开更多
基金supported by the National Natural Science Foundation of China(Nos.22162021 and 21862013)the Natural Science Foundation of Ningxia Province(Nos.2021AAC03057 and 2023AAC03015).
文摘A scalable strategy for the convenient and rapid preparation of nitrogen-doped carbon-coated iron-based alloy catalysts was developed.By controlling the type and amount of metal salts in the precursor,various types of nitrogen-doped carbon-coated alloy catalysts can be prepared in a targeted manner.Fe_(2)Ni2@CN materials with small particle sizes and relatively homogeneous basic sites showed promising results in the N-alkylation reaction of benzyl alcohol with aniline(optimum yield:99%).It is worth noting that the catalyst can also be magnetically separated and recovered after the reaction,and its performance can be regenerated through simple calcination.Furthermore,it was confirmed by kinetic experiments that the activation of C–H at the benzyl alcohol benzylic position is the rate-determining step(RDS).According to density flooding theory calculations,Fe_(2)Ni2@CN catalysts require less energy than other materials(Fe@CN and Ni@CN)for the RDS(dehydrogenation reaction)process.Therefore N-alkylation reactions are more easily carried out on Fe_(2)Ni2@CN catalysts,which may be the reason for the best catalytic activity of Fe-Ni alloy materials.These carbon-coated alloy materials will show great potential in more types of heterogeneous catalysis.
基金supported by the National Natural Science Foundation of China(Nos.21806106,51861145101,21777096 and 21777097)Shanghai Shuguang Grant(No.17SG11)the China Postdoctoral Science Foundation(Nos.2017M621483 and 2018T110397)。
文摘Chlorinated organic pollutants(COPs)have caused serious contaminants in soil and groundwater,hence developing methods to remove these pollutants is necessary and urgent.By a simple hydrothermal method,we synthesized the bimetallic iron-nickel sulfide(FeNiS)particles which exhibited excellent catalytic property of COPs removal.FeNiS was chosen as the peroxydisulfate(PDS)activator to removal COPs including 4-chlorophenol(4-CP),1,4-dichlorophenol(1,4-DCP)and 2,4,6-trichlorophenol(2,4,6-TCP).The results show that FeNiS can efficiently activate PDS to produce sulfate radical(SO4·-)which plays major role in the oxidative dechlorination and degradation due to its strong oxidizing property and the ability of producing hydroxyl radicals(·OH)in the alkaline condition.Meanwhile,the Cl-abscised from COPs during the dechlorination can turn into the chlorine radicals and enhance the degradation and cause further mineralization of intermediate products.This bimetallic FeNiS catalyst is a promising PDS activator for removal of chlorinated organics.
