The electrocatalysts containing cobalt-pyrrolic nitrogen-carbon(Co-N_(4)-C)moiety for CO_(2)reduction reaction(CO_(2)RR)have caught much attention.However;the effects of Co valence state and its synergy with gra-phene...The electrocatalysts containing cobalt-pyrrolic nitrogen-carbon(Co-N_(4)-C)moiety for CO_(2)reduction reaction(CO_(2)RR)have caught much attention.However;the effects of Co valence state and its synergy with gra-phene substrate are not clear yet.In this work;cobalt porphyrin(CoTPP)molecule with the intrinsic Co-N_(4)-C moiety is successfully combined with graphene oxide(GO)via three kinds of liquid-phase methods.The ratio of CoTPP to GO and the valence state of Co atom are studied to explore their catalysis for CO_(2)RR to CO.It is found that axial-ly-coordinated Co(III)TPPCl/GO nanocomposites synthesized via a chemical method exhibit better ability for CO_(2)RR;as compared with Co(II)TPP+GO and/or Co(III)TPPCl+GO nanocomposites obtained via a physically mixing way.After optimizing the ratio of CoTPP to GO;the Faradaic efficiency(FE)is more than 90%for CO_(2)RR to CO between−0.7 and−0.8 V vs.reversible hydrogen electrode(RHE)in Co(III)TPPCl/GO75.The synergy be-tween CoTPP and GO and the effect of Co valence state are systematically investigated;indicating that their strong interaction plays the key role in electrocatalytic CO_(2)RR.展开更多
基金supported by the National Natural Science Foundation of China (Nos. 21705150 and 21473204)Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China (No. 2021ZR124)
文摘The electrocatalysts containing cobalt-pyrrolic nitrogen-carbon(Co-N_(4)-C)moiety for CO_(2)reduction reaction(CO_(2)RR)have caught much attention.However;the effects of Co valence state and its synergy with gra-phene substrate are not clear yet.In this work;cobalt porphyrin(CoTPP)molecule with the intrinsic Co-N_(4)-C moiety is successfully combined with graphene oxide(GO)via three kinds of liquid-phase methods.The ratio of CoTPP to GO and the valence state of Co atom are studied to explore their catalysis for CO_(2)RR to CO.It is found that axial-ly-coordinated Co(III)TPPCl/GO nanocomposites synthesized via a chemical method exhibit better ability for CO_(2)RR;as compared with Co(II)TPP+GO and/or Co(III)TPPCl+GO nanocomposites obtained via a physically mixing way.After optimizing the ratio of CoTPP to GO;the Faradaic efficiency(FE)is more than 90%for CO_(2)RR to CO between−0.7 and−0.8 V vs.reversible hydrogen electrode(RHE)in Co(III)TPPCl/GO75.The synergy be-tween CoTPP and GO and the effect of Co valence state are systematically investigated;indicating that their strong interaction plays the key role in electrocatalytic CO_(2)RR.
