Combined Electron and Structure Manipulation on Fe-Containing N-Doped Carbon Nanotubes To Boost Bifunctional Oxygen Electrocatalysis

Zhao, Lei; Wang, Qichen; Zhang, Xinqi; Deng, Cheng; Li, Zhihong; Lei, Yongpeng; Zhu, Mengfu

doi:10.1021/acsami.8b09197

Cited by 76 publications

(36 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The morphology of the Co/Co–N–C without obvious change after cycling test can be seen from the TEM images in Figure S16, Supporting Information, which further indicated the good structure stability of the present self‐supported electrode. The presented Co/Co–N–C catalyst exhibited much higher power density than the other reported M–N–C structures, such as Co@NC (105 mW cm −2 at 120.0 mA cm −2 ), Co/N–CNSNs (81.7 mW cm −2 at 140.0 mA cm −2 ), CoN, B‐CSs (100.4 mW cm −2 at 110 mA cm −2 ), and Fe–N–CNT/OMC catalyst (96.1 mW cm −2 at 110 mA cm −2 ) . It is worth noting that the introduction of N atoms and transition metal on carbon materials could significantly improve the electrocatalytic activity, attributing to the modification of the local electronic structure of carbon surface.…”

mentioning

confidence: 81%

Co Nanoislands Rooted on Co–N–C Nanosheets as Efficient Oxygen Electrocatalyst for Zn–Air Batteries

et al. 2019

View full text Add to dashboard Cite

been devoted to various energy storage and conversion systems. [1,2] Metal-air batteries, especially Zn-air batteries (ZABs) have been regarded as a promising energy storage system due to their low-cost, high theoretical specific energy density (1084 Wh kg −1 ), and environmental friendliness. [3][4][5] Nevertheless, the multistep and proton-coupled electron transfer processes of the reversible oxygen reactions lead to sluggish kinetics for oxygen reduction (ORR) and oxygen evolution (OER) at aircathode, which are the bottlenecks of inefficient and unideal lifetime. [6] The current benchmark catalysts for simply ORR or OER are precious-metal-based catalysts (Pt, Ir, RuO 2 , etc.), but their high cost, supply scarcity, and poor bifunctional catalytic characters have greatly restricted their applications in ZABs. [7,8] In response, various transition-based catalysts with high activity and good durability have been explored, such as transition metal oxides, chalcogenides, and metal-heteroatom doped carbon materials. [9][10][11][12][13][14] Despite significant progress, current bifunctional catalysts are still facing the problems of insufficient activity and stability together with poor mass transport properties.Alternatively, metal-nitrogen-carbon (M-N-C) systems comprising the earth abundant transition metals and catalytic active metalN x centers with carbonized ligand have received growing interest due to their low cost and excellent catalytic activities. [15][16][17] Specially, Co-N-C has emerged as ORR catalyst for improvement the overall performance of ZABs. [18,19] Inspired by the excellent OER performance of Co-based catalysts (e.g., cobalt metal and cobalt oxide) and intrinsically electrical conductivity of Co metal, [20,21] so constructing hierarchical structure of Co-N-C contained Co metal maybe an effective way to promote the bifunctional ORR/OER activity. At present, various strategies have been applied to synthesize Co-N-C structures. Traditionally, carbonized the Co-based precursors (such as porphyrins and phthalocyanines) have been developed for several decades to synthesize metal contained N-doped carbon nanostructures, [22,23] but always suffer from large nanoparticles size and ununiformed structures. Hence, much efforts have been devoted to construct Co-N-C-based catalysts with novel morphology and structures, such as core-shell or single-atom dispersed Co-N-C catalysts combined with carbon nanotubes Developing non-precious-metal bifunctional oxygen reduction and evolution reaction (ORR/OER) catalysts is a major task for promoting the reaction efficiency of Zn-air batteries. Co-based catalysts have been regarded as promising ORR and OER catalysts owing to the multivalence characteristic of cobalt element. Herein, the synthesis of Co nanoislands rooted on Co-N-C nanosheets supported by carbon felts (Co/Co-N-C) is reported. Co nanosheets rooted on the carbon felt derived from electrodeposition are applied as the self-template and cobalt source. The synergistic effect of metal Co islands with OER a...

show abstract

mentioning

confidence: 81%

Co Nanoislands Rooted on Co–N–C Nanosheets as Efficient Oxygen Electrocatalyst for Zn–Air Batteries

et al. 2019

View full text Add to dashboard Cite

show abstract

“…[5,6] To maximize the catalytic efficiency, a rather crucial point of the matter is using the phenomenon of charge delocalization in carbon framework, in particular by introducing transition metals into heteroatom-doped carbon systems. [7][8][9][10][11] It is found that Fe-N is the most common active site, portraying the best ORR property. Although the activities of prevailing Fe-N/C catalysts are comparable to or even better than Pt/C catalyst in alkaline solution, they are still vulnerable in acidic medium.…”

Section: Introductionmentioning

confidence: 99%

Pearl Necklace Fibrous Carbon Sharing Fe–N/Fe–P Dual Active Sites as Efficient Oxygen Reduction Catalyst in Broad Media and for Liquid/Solid‐State Rechargeable Zn–Air Battery

2020

Energy Tech

View full text Add to dashboard Cite

Optimized catalysts are attractive from the standpoint of energy storage and conversion. Herein, a pearl necklace fibrous carbon catalyst with Fe–N/Fe–P dual active sites (Fe–P/NHCF) is fabricated via carbonization–phosphidation of metal–organic framework (MOF)/polyacrylonitrile nanofibers. Benefiting from Fe–N/Fe–P doping‐induced active sites, accompanied by particular hierarchical porous merit and a 1D necklace network to facilitate the oxygen reduction reaction (ORR), it exhibits a half‐wave potential of 0.82 V in alkaline medium and outperforms commercial Pt/C in terms of stability in acid medium. Furthermore, a low voltage gap (1.04 V) is acquired in a liquid Zn–air battery with Fe–P/NHCF as the cathode. Meanwhile, the portable solid‐state Zn–air battery displays an open circuit voltage of 1.32 V and a power density of 42 mW cm−2. This strategy puts forward a protocol to develop tailored geometry with dual active sites for ORR in alkaline/acid media, which is expected to promote devices of practical significance.

show abstract

“…Extensive studies have been carried out to combine transition metals with carbon materials to enhance the electric conductivity as well as the dispersion of metal-based active sites [16,17]. Moreover, theoretical calculations suggested that dopants of heteroatoms in the sp 2 lattice of graphitic carbon can turn the oxygen adsorption mode into diatomic adsorption, which changes the electron cloud of the graphite carbon and significantly enhances the kinetics of the ORR [18][19][20].…”

Section: Introductionmentioning

confidence: 99%

Stepwise Fabrication of Co-Embedded Porous Multichannel Carbon Nanofibers for High-Efficiency Oxygen Reduction

et al. 2019

View full text Add to dashboard Cite

HIGHLIGHTS• An interconnected structure is developed by evaporation of zinc species using a ZnCo 2 O 4 precursor as the cobalt resource, enabling communications between channels as well as homogeneous loading of active sites.• A shell structure of Co 3 O 4 is formed on the surface of a zero-valent Co 0 core during a stepwise carbothermic reduction of ZnCo 2 O 4 .• The Co-embedded multichannel carbon nanofibers exhibit not only a superior half-wave potential, but also an excellent durability compared to those of the commercial 30% Pt/C. ABSTRACT A novel nonprecious metal material consisting of Coembedded porous interconnected multichannel carbon nanofibers (Co/ IMCCNFs) was rationally designed for oxygen reduction reaction (ORR) electrocatalysis. In the synthesis, ZnCo 2 O 4 was employed to form interconnected mesoporous channels and provide highly active Co 3 O 4 /Co core-shell nanoparticle-based sites for the ORR. The IMC structure with a large synergistic effect of the N and Co active sites provided fast ORR electrocatalysis kinetics. The Co/IMCCNFs exhibited a high half-wave potential of 0.82 V (vs. reversible hydrogen electrode) and excellent stability with a current retention up to 88% after 12,000 cycles in a current-time test, which is only 55% for 30 wt% Pt/C.

show abstract

Combined Electron and Structure Manipulation on Fe-Containing N-Doped Carbon Nanotubes To Boost Bifunctional Oxygen Electrocatalysis

Cited by 76 publications

References 49 publications

Co Nanoislands Rooted on Co–N–C Nanosheets as Efficient Oxygen Electrocatalyst for Zn–Air Batteries

Co Nanoislands Rooted on Co–N–C Nanosheets as Efficient Oxygen Electrocatalyst for Zn–Air Batteries

Pearl Necklace Fibrous Carbon Sharing Fe–N/Fe–P Dual Active Sites as Efficient Oxygen Reduction Catalyst in Broad Media and for Liquid/Solid‐State Rechargeable Zn–Air Battery

Stepwise Fabrication of Co-Embedded Porous Multichannel Carbon Nanofibers for High-Efficiency Oxygen Reduction

Contact Info

Product

Resources

About