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Developing non-precious metal catalyst with high activity, good stability and low cost for electrocatalytic oxygen reduction reaction(ORR) is critical for the wide application of energy conversion system. Here, we developed a cost–effective synthetic strategy via silica assistance to obtain a novel Fe_3C/Fe–N_x–C(named as COPBP-PB-Fe-900-SiO_2) catalyst with effective active sites of Fe–N_xand Fe_3C from the rational design two-dimensional covalent organic polymer(COPBP-PB). The nitrogen-rich COP effectively promotes the formation of active Fe–N_x sites. Additionally, the silica not only can effectively suppress the formation of large Fe-based particles in the catalysts, but also increases the degree of carbonization of the catalyst.The as-prepared COPBP-PB-Fe-900-SiO_2 catalyst exhibits high electrocatalytic activity for ORR with a halfwave potential of 0.85 V vs. reversible hydrogen electrode(RHE), showing comparable activity as compared with the commercial Pt/C catalysts in alkaline media. Moreover, this catalyst also shows a high stability with a nearly constant onset potential and half-wave potential after 10,000 cycles. The present work is highly meaningful for developing ORR electrocatalysts toward wide applications.
Developing non-precious metal catalyst with high activity, good stability and low cost for electrocatalytic oxygen reduction reaction (ORR) is critical for the wide application of energy conversion system. Here, we developed a cost-effective synthetic strategy via silica assistance to obtain a novel named Fe_3C / Fe-N_x-C (named as COPBP-PB-Fe-900-SiO_2) catalyst with effective active sites of Fe-N_xand Fe_3C from the rational design two-dimensional covalent organic polymer rich COP effectively promotes the formation of active Fe-N_x sites. Additionally, the silica not only can effectively suppress the formation of large Fe-based particles in the catalysts, but also increases the degree of carbonization of the catalyst.The as-prepared COPBP -PB-Fe-900-SiO 2 catalyst exhibits high electrocatalytic activity for ORR with a halfwave potential of 0.85 V vs. reversible hydrogen electrode (RHE), showing comparable activity as the commercial Pt / C catalysts i n alkaline media. Moreover, this catalyst also shows a high stability with a nearly constant onset potential and half-wave potential after 10,000 cycles. The present work is highly meaningful for developing ORR electrocatalysts toward wide applications.