Cu-based materials are commonly used in electrocatalytic nitrate reduction reactions(NO 3 RR).NO 3 RR is a“two birds,one stone”approach,simultaneously removing NO 3−pollutants and producing valuable ammonia(NH 3).Ho...Cu-based materials are commonly used in electrocatalytic nitrate reduction reactions(NO 3 RR).NO 3 RR is a“two birds,one stone”approach,simultaneously removing NO 3−pollutants and producing valuable ammonia(NH 3).However,the strong coordination between the NO 3−intermediate and the catalytic active sites seriously hinders the conversion effi ciency.Here,we determined that,through encapsulation strategies,the carbon layer could weaken the NO 3−intermediate binding to active sites,resulting in higher NH 3 yields.We experimentally fabricated electrocatalysts,i.e.,Cu nanoparticles encapsulating(or loaded on)N-doped carbon nanofi bers(NCNFs)called Cu@NCNFs(Cu-NCNFs),using electrostatic spinning.As a result,Cu@NCNFs can achieve NH 3 yields of 17.08 mg/(h·mg cat)at a voltage of−0.84 V and a Faraday effi ciency of 98.15%.Meanwhile,the electrochemical properties of the Cu nanoparticles on the surface of carbon fi bers(Cu-NCNFs)are lower than those of the Cu@NCNFs.The in situ Raman spectra of Cu@NCNFs and Cu-NCNFs under various reduction potentials during the NO 3 RR process show that catalyst encapsulation within carbon layers can eff ectively reduce the adsorption of N species by the catalyst,thus improving the catalytic performance in the nitrate-to-ammonia catalytic conversion process.展开更多
基金This work was financially supported by the National Natural Science Foundation of China(Nos.22208048,22202174,62001097 and 21576238)the Natural Science Foundation of Heilongjiang Province(No.YQ2022B001)We would like to acknowledge the technical support from Analysis and Testing Center of Northeast Forestry University.
文摘Cu-based materials are commonly used in electrocatalytic nitrate reduction reactions(NO 3 RR).NO 3 RR is a“two birds,one stone”approach,simultaneously removing NO 3−pollutants and producing valuable ammonia(NH 3).However,the strong coordination between the NO 3−intermediate and the catalytic active sites seriously hinders the conversion effi ciency.Here,we determined that,through encapsulation strategies,the carbon layer could weaken the NO 3−intermediate binding to active sites,resulting in higher NH 3 yields.We experimentally fabricated electrocatalysts,i.e.,Cu nanoparticles encapsulating(or loaded on)N-doped carbon nanofi bers(NCNFs)called Cu@NCNFs(Cu-NCNFs),using electrostatic spinning.As a result,Cu@NCNFs can achieve NH 3 yields of 17.08 mg/(h·mg cat)at a voltage of−0.84 V and a Faraday effi ciency of 98.15%.Meanwhile,the electrochemical properties of the Cu nanoparticles on the surface of carbon fi bers(Cu-NCNFs)are lower than those of the Cu@NCNFs.The in situ Raman spectra of Cu@NCNFs and Cu-NCNFs under various reduction potentials during the NO 3 RR process show that catalyst encapsulation within carbon layers can eff ectively reduce the adsorption of N species by the catalyst,thus improving the catalytic performance in the nitrate-to-ammonia catalytic conversion process.
