Mo2C/VC heterojunction embedded in graphitic carbon network: An advanced electrocatalyst for hydrogen evolution

Huang, Chao; Miao, Xiaowei; Pi, Chaoran; Gao, Biao; Zhang, Xuming; Qin, Ping; Huo, Kaifu; Peng, Xiang; Chu, Paul K.

doi:10.1016/j.nanoen.2019.03.088

Cited by 132 publications

(69 citation statements)

References 47 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…. . ARTICLES commercial Pt/C shows an overpotential of 29 mV, consistent with the previously reported literature [44,45]. Tafel slope is a crucial parameter to assess the rate-limiting step and kinetics in HER.…”

Section: Science China Materialssupporting

confidence: 89%

Melamine-assisted synthesis of ultrafine Mo2C/Mo2N@N-doped carbon nanofibers for enhanced alkaline hydrogen evolution reaction activity

et al. 2020

View full text Add to dashboard Cite

Noble metal-free electrocatalysts with high activity are highly desirable for the large-scale application of hydrogen evolution reaction (HER). Mo 2 C-based nanomaterials have been proved as a promising alternative to noble metal-based electrocatalysts owing to the Pt-resembled d-band density and optimal intermediates-adsorption properties. However, the aggregation and excessive growth of crystals often occur during their high-temperature synthesis procedure, leading to low catalytic utilization. In this study, the ultrafine Mo 2 C/Mo 2 N heterostructure with large surface and interface confined in the N-doped carbon nanofibers (N-CNFs) was obtained by a melamine-assisted method. The synergistic effect of Mo 2 C/Mo 2 N heterostructure and plenty active sites exposed on the surface of ultrafine nanocrystals improves the electrocatalytic activity. Meanwhile, the N-CNFs ensure fast charge transfer and high structural stability during reactions. Moreover, the in-situ synthesis method strengthens the interfacial coupling interactions between Mo 2 C/Mo 2 N heterostructure and N-CNFs, further enhancing the electronic conductivity and electrocatalytic activity. Owing to these advantages, Mo 2 C/Mo 2 N@N-CNFs exhibit excellent HER performance with a low overpotential of 75 mV at a current density of 10 mV cm −2 in alkaline solution, superior to the single-phased Mo 2 C counterpart and recently reported Mo 2 C/ Mo 2 N-based catalysts. This study highlights a new effective strategy to design efficient electrocatalysts via integrating heterostructure, nanostructure and carbon modification.

show abstract

Section: Science China Materialssupporting

confidence: 89%

Melamine-assisted synthesis of ultrafine Mo2C/Mo2N@N-doped carbon nanofibers for enhanced alkaline hydrogen evolution reaction activity

et al. 2020

View full text Add to dashboard Cite

show abstract

“…Apparently, there are some nano‐heterostructure boundaries between them. And, these incoherent interfaces can provide abundant defects and strong interaction for increasing the active sites to improve the electrochemical performances . The heterostructure of Fe 7 S 8 /α‐FeOOH is shown clearly in Figure S8, Supporting Information, and the inset in Figure e, which reveals that the α‐FeOOH and Fe 7 S 8 are interweaved with each other to provide more interfacial area.…”

Section: Resultsmentioning

confidence: 96%

“…To further obtain the detailed crystal parameters, high-magnification STEM tests were carried out (Figure 2d www.advelectronicmat.de heterojunction structures that were found. [30,31] The heterostructure of Fe 7 S 8 /α-FeOOH is shown clearly in Figure S8, Supporting Information, and the inset in Figure 2e, which reveals that the α-FeOOH and Fe 7 S 8 are interweaved with each other to provide more interfacial area. The lattice distance of 0.250 nm is attributed to the (040) plane of α-FeOOH while that of 0.298 nm to the (200) plane of Fe 7 S 8 .…”

Section: Resultsmentioning

confidence: 98%

Electric‐Field‐Assisted Enhanced Electron Transfer to Boost Supercapacitor Negative Electrode Performance for a Fabricated Fe₇S₈/α‐FeOOH Nano‐Heterostructure

Zhang

Kong

Zhang

et al. 2019

Adv Elect Materials

View full text Add to dashboard Cite

nevertheless, they usually put undue emphasis on the capacity of the positive electrode, instead. There are few reports that discuss the negative electrode materials relatively. As a result, the capacity of the negative electrodes is much lower than that of the positive electrodes, and the capacity mismatch between the positive and negative electrodes is more serious. [6] As a matter of fact, similar to "cask effect," the capacity of the negative electrode is the shortest plank for supercapacitor, which decides how much energy capacity the supercapacitor can store. In other words, the way that can increase the capacity of the negative electrode materials, can remedy the low energy density deficiency of supercapacitor. [7] Looking at what predecessors have been developed for constructing the supercapacitor negative electrode, carbon and Fe-based materials are two major electrodes that can be utilized. [8][9][10] Due to the redox characteristic of Fe-based materials, it is believed to have the higher theoretical capacity compared with carbon materials that presents double layer capacitance characteristics. [11] To our disappointment, the poor electrical conductivity, which affects the efficiency of electronic transmission, resulted in low supercapacitor performance embodiment, far less than what was expected. [12,13] Therefore, how to improve the electrical conductivity to enhance the efficiency of electron transfer is the most important factor when designing and fabricating an Fe-based negative electrode material. [14] To address this challenge, one of the strategies is to fabricate composites with carbon materials. [4,15] On account of the excellent electrical conductivity of carbon materials, the Fe-based compand/carbon composites show good electrical conductivity. However, the low theoretical capacity of carbon materials limits the capacity promotion of Fe-based compand/ carbon composites. Another method is to rationally design a hierarchical nanostructure. [5,14,16,17] Core-shell structure is believed to be a good choice, where materials with good electrical conductivity are used as the core and materials with high theoretical capacity are used as the shell. [13,[18][19][20] Therefore, the good electrochemical performance has been ascribed to its unique structure, which endows the electrode with large specific area and facilitates the contact between the electrode and The shortcoming of Fe-based materials, their poor electron transfer efficiency, restricts their electrochemical performance severely. An electric field (E) is induced by an Fe 7 S 8 /α-FeOOH nano-heterostructure (SACF) via two simple immersion steps at room temperature. The charge transfer from α-FeOOH to Fe 7 S 8 spontaneously establishes an intrinsic electric field at the Fe 7 S 8 /α-FeOOH nano-heterostructure boundary. Additionally, the relationship between structure and property is investigated by structural characterization and density functional theory calculations that are used to explain the electron transfer mechanism and good wettabilit...

show abstract

“…Owing to the s-and p-orbitals of neighboring C atoms, the d orbitals of metals in transition metal carbides are broadened and exhibit a Pt-like d band center, making the carbides show noble-metal-like physiochemical properties. As a result, carbides have been regarded as excellent HER electrocatalysts due to their metallic electronic structures, high conductivity, and earth abundance [111][112][113][114][115][116]. Tuning the phase and engineering the mesostructure can significantly enhance the activity.…”

Section: Carbidesmentioning

confidence: 99%

微纳结构过渡金属化合物能源转化电催化剂研究进展

et al. 2020

View full text Add to dashboard Cite

The rapid consumption of fossil fuels has caused increasingly climatic issues and energy crisis, which leads to the urgent demand for developing sustainable and clean energies. Electrocatalysts play a key role in the development of electrochemical energy conversion and storage devices. Especially, developing efficient and cost-effective catalysts is important for the large-scale application of these devices. Among various electrocatalyst candidates, earth abundant transition metal compound (TMC)-based electrocatalysts are being widely and rapidly studied owing to their high electrocatalytic performances. This paper reviews the recent and representative advances in efficient TMC-based electrocatalysts (i.e., oxides, sulfides, selenides, phosphides, carbides and nitrides) for energy electrocatalytic reactions, including hydrogen evolution reaction (HER), oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). Different compounds with different applications are summarized and the relative mechanisms are also discussed. The strategies for developing earth-abundant and low-cost TMC-based electrocatalysts are introduced. In the end, the current challenges and future perspectives in the development of TMC research are briefly discussed. This review also provides the latest advance and outlines the frontiers in TMC-based electrocatalysts, which should provide inspirations for the further development of low-cost and high-efficiency catalysts for sustainable clean energy technologies.

show abstract

Mo2C/VC heterojunction embedded in graphitic carbon network: An advanced electrocatalyst for hydrogen evolution

Cited by 132 publications

References 47 publications

Melamine-assisted synthesis of ultrafine Mo2C/Mo2N@N-doped carbon nanofibers for enhanced alkaline hydrogen evolution reaction activity

Melamine-assisted synthesis of ultrafine Mo2C/Mo2N@N-doped carbon nanofibers for enhanced alkaline hydrogen evolution reaction activity

Electric‐Field‐Assisted Enhanced Electron Transfer to Boost Supercapacitor Negative Electrode Performance for a Fabricated Fe₇S₈/α‐FeOOH Nano‐Heterostructure

微纳结构过渡金属化合物能源转化电催化剂研究进展

Contact Info

Product

Resources

About

Mo2C/VC heterojunction embedded in graphitic carbon network: An advanced electrocatalyst for hydrogen evolution

Cited by 132 publications

References 47 publications

Melamine-assisted synthesis of ultrafine Mo2C/Mo2N@N-doped carbon nanofibers for enhanced alkaline hydrogen evolution reaction activity

Melamine-assisted synthesis of ultrafine Mo2C/Mo2N@N-doped carbon nanofibers for enhanced alkaline hydrogen evolution reaction activity

Electric‐Field‐Assisted Enhanced Electron Transfer to Boost Supercapacitor Negative Electrode Performance for a Fabricated Fe7S8/α‐FeOOH Nano‐Heterostructure

微纳结构过渡金属化合物能源转化电催化剂研究进展

Contact Info

Product

Resources

About

Electric‐Field‐Assisted Enhanced Electron Transfer to Boost Supercapacitor Negative Electrode Performance for a Fabricated Fe₇S₈/α‐FeOOH Nano‐Heterostructure