Heteroatom-doped carbon materials as alternative catalysts for oxygen reduction reaction(ORR)have drawn increasing attention due to their tunable chemical and electronic structures for achieving high activity and stab...Heteroatom-doped carbon materials as alternative catalysts for oxygen reduction reaction(ORR)have drawn increasing attention due to their tunable chemical and electronic structures for achieving high activity and stability. However, there still remains a great challenge to fabricate porous heteroatoms dual-doped carbons with uniformly doping in a facile and controllable way. Herein,imidazole/imidazolium-functionalized metal-organic frameworks(MOFs) are employed as precursors and templates to achieve porous nitrogen and halogen dual-doped nanocarbons. Among these carbon materials, the as-prepared nitrogen/bromine dual-doped catalyst BrNC-800 exhibits the best ORR performance with a positive half-wave potential at 0.80 V(vs. RHE) in 0.1 mol L-1 KOH, which is comparable to the benchmark commercial 20 wt% Pt/C catalyst. BrNC-800 shows excellent long term stability and methanol tolerance.This work provides a facile approach to fabricate highly efficient heteroatoms dual-doped carbon catalysts for energy conversion.展开更多
A metal-organic framework(MOF)-conductive polymer composite film was constructed from PCN-222(Fe)nanoparticles and PEDOT:PSS solution by simple drop-casting approach.The composite film was tested as an electrocatalyti...A metal-organic framework(MOF)-conductive polymer composite film was constructed from PCN-222(Fe)nanoparticles and PEDOT:PSS solution by simple drop-casting approach.The composite film was tested as an electrocatalytic device for oxygen reduction reaction(ORR).The combination of PCN-222(Fe)MOF particles and conductive PEDOT matrix facilitates electron transfer in the composite material and improves the ORR performance of PCN-222(Fe).Levich plot and H_(2)O_(2)quantification experiment show that PCN-222(Fe)/PEDOT:PSS film mainly catalyzes two-electron oxygen reduction and produces H_(2)O_(2).展开更多
Helical metal-organic frameworks(MOFs)were used as templates or precursors to fabricate helical carbon nanorods(HCNRs)for the first time.Helical carbon contains many topological defects such as pentagonal or heptagona...Helical metal-organic frameworks(MOFs)were used as templates or precursors to fabricate helical carbon nanorods(HCNRs)for the first time.Helical carbon contains many topological defects such as pentagonal or heptagonal carbons,which have the potential to facilitate oxygen reduction reactions(ORR).HCNRs show more positive onset/halfwave reduction potentials and higher limited current density than straight carbon nanorods(SCNRs).They also exhibit four-electron oxygen reduction in tests of ORR,while the alternative SCNRs prefer a two-electron reduction mechanism.Experimental and theoretical studies reveal that these enhanced ORR activities can be attributed to pentagon/heptagon defects in HCNRs.This work provides an effective strategy to synthesize helical,defect-rich carbon materials and opens up a new perspective for utilization of a spiral effect for the development of more effective electrocatalysts.展开更多
基金the financial support from the National Key Research and Development Program of China (2018YFA0208600)National Basic Research Program of China (973 Program, 2014CB845605)+3 种基金Key Research Program of Frontier Science, Chinese Academy of Sciences (QYZDJ-SSW-SLH045)Strategic Priority Research Program of the Chinese Academy of Sciences (XDB20000000)National Natural Science Foundation of China (21671188, 21871263, 21521061 and 21331006)Youth Innovation Promotion Association,Chinese Academy of Sciences (2014265)
文摘Heteroatom-doped carbon materials as alternative catalysts for oxygen reduction reaction(ORR)have drawn increasing attention due to their tunable chemical and electronic structures for achieving high activity and stability. However, there still remains a great challenge to fabricate porous heteroatoms dual-doped carbons with uniformly doping in a facile and controllable way. Herein,imidazole/imidazolium-functionalized metal-organic frameworks(MOFs) are employed as precursors and templates to achieve porous nitrogen and halogen dual-doped nanocarbons. Among these carbon materials, the as-prepared nitrogen/bromine dual-doped catalyst BrNC-800 exhibits the best ORR performance with a positive half-wave potential at 0.80 V(vs. RHE) in 0.1 mol L-1 KOH, which is comparable to the benchmark commercial 20 wt% Pt/C catalyst. BrNC-800 shows excellent long term stability and methanol tolerance.This work provides a facile approach to fabricate highly efficient heteroatoms dual-doped carbon catalysts for energy conversion.
基金funded by the Talent Recruitment Program of Fujian Province,China
文摘A metal-organic framework(MOF)-conductive polymer composite film was constructed from PCN-222(Fe)nanoparticles and PEDOT:PSS solution by simple drop-casting approach.The composite film was tested as an electrocatalytic device for oxygen reduction reaction(ORR).The combination of PCN-222(Fe)MOF particles and conductive PEDOT matrix facilitates electron transfer in the composite material and improves the ORR performance of PCN-222(Fe).Levich plot and H_(2)O_(2)quantification experiment show that PCN-222(Fe)/PEDOT:PSS film mainly catalyzes two-electron oxygen reduction and produces H_(2)O_(2).
基金financial support from the National Key Research and Development Program of China(2018YFA0208600 and 2017YFA0700100)the Key Research Program of Frontier Science,CAS(QYZDJ-SSW-SLH045)+2 种基金the National Natural Science Foundation of China(21671188,21871263 and 22033008)the Strategic Priority Research Program of CAS(XDB20000000)the Youth Innovation Promotion Association,CAS(2014265)。
文摘Helical metal-organic frameworks(MOFs)were used as templates or precursors to fabricate helical carbon nanorods(HCNRs)for the first time.Helical carbon contains many topological defects such as pentagonal or heptagonal carbons,which have the potential to facilitate oxygen reduction reactions(ORR).HCNRs show more positive onset/halfwave reduction potentials and higher limited current density than straight carbon nanorods(SCNRs).They also exhibit four-electron oxygen reduction in tests of ORR,while the alternative SCNRs prefer a two-electron reduction mechanism.Experimental and theoretical studies reveal that these enhanced ORR activities can be attributed to pentagon/heptagon defects in HCNRs.This work provides an effective strategy to synthesize helical,defect-rich carbon materials and opens up a new perspective for utilization of a spiral effect for the development of more effective electrocatalysts.
