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1.
N,P‐Codoped Carbon Networks as Efficient Metal‐free Bifunctional Catalysts for Oxygen Reduction and Hydrogen Evolution Reactions
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Dr. Jintao Zhang Prof. Liangti Qu Prof. Gaoquan Shi Jiangyong Liu Prof. Jianfeng Chen Prof. Liming Dai 《Angewandte Chemie (International ed. in English)》2016,55(6):2230-2234
The high cost and scarcity of noble metal catalysts, such as Pt, have hindered the hydrogen production from electrochemical water splitting, the oxygen reduction in fuel cells and batteries. Herein, we developed a simple template‐free approach to three‐dimensional porous carbon networks codoped with nitrogen and phosphorus by pyrolysis of a supermolecular aggregate of self‐assembled melamine, phytic acid, and graphene oxide (MPSA/GO). The pyrolyzed MPSA/GO acted as the first metal‐free bifunctional catalyst with high activities for both oxygen reduction and hydrogen evolution. Zn–air batteries with the pyrolyzed MPSA/GO air electrode showed a high peak power density (310 W g?1) and an excellent durability. Thus, the pyrolyzed MPSA/GO is a promising bifunctional catalyst for renewable energy technologies, particularly regenerative fuel cells. 相似文献
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3.
Cobalt‐Embedded Nitrogen‐Rich Carbon Nanotubes Efficiently Catalyze Hydrogen Evolution Reaction at All pH Values
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Dr. Xiaoxin Zou Xiaoxi Huang Dr. Anandarup Goswami Dr. Rafael Silva Dr. Bhaskar R. Sathe Eliška Mikmeková Prof. Tewodros Asefa 《Angewandte Chemie (International ed. in English)》2014,53(17):4372-4376
Despite being technically possible, splitting water to generate hydrogen is still practically unfeasible due mainly to the lack of sustainable and efficient catalysts for the half reactions involved. Herein we report the synthesis of cobalt‐embedded nitrogen‐rich carbon nanotubes (NRCNTs) that 1) can efficiently electrocatalyze the hydrogen evolution reaction (HER) with activities close to that of Pt and 2) function well under acidic, neutral or basic media alike, allowing them to be coupled with the best available oxygen‐evolving catalysts—which also play crucial roles in the overall water‐splitting reaction. The materials are synthesized by a simple, easily scalable synthetic route involving thermal treatment of Co2+‐embedded graphitic carbon nitride derived from inexpensive starting materials (dicyandiamide and CoCl2). The materials’ efficient catalytic activity is mainly attributed to their nitrogen dopants and concomitant structural defects. 相似文献
4.
Dr. Yanqiang Li Huiyong Huang Dr. Siru Chen Chao Wang Prof. Tingli Ma 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(10):2637-2644
It is of increasing importance to develop highly active and economical oxygen reduction reaction (ORR) electrocatalysts, which have great significance for the large-scale implementation of various energy conversion systems, including metal–air batteries and fuel cells. Herein, a novel method to synthesize FeNx-decorated carbon nanotubes as a high-efficiency ORR catalyst, by utilizing ZnO nanowires as a sacrificial template and a Fe–polydopamine complex as metal and carbon sources, is reported. The obtained catalyst shows great potential for replacing Pt/C as the ORR catalyst under various pH conditions, from alkaline to acidic electrolytes. The high conductivity, large surface area of the carbon nanotube, and highly active FeNx species contributed greatly to the high performance of the catalyst. The work presented herein paves a new way for the synthesis of 1D porous nanomaterials for a broad range of energy-related applications. 相似文献
5.
One‐Step Hydrothermal Synthesis of Nitrogen‐Doped Carbon Nanotubes as an Efficient Electrocatalyst for Oxygen Reduction Reactions
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Dr. Lisong Chen Dr. Xiangzhi Cui Dr. Yongxia Wang Min Wang Dr. Fangming Cui Dr. Chenyang Wei Dr. Weimin Huang Dr. Zile Hua Dr. Lingxia Zhang Prof. Jianlin Shi 《化学:亚洲杂志》2014,9(10):2915-2920
A high amount of heteroatom doping in carbon, although favorable for enhanced density of catalytically active sites, may lead to substantially decreased electroconductivity, which is necessary for the electrochemical oxygen reduction reaction. Herein, a relatively low amount of nitrogen was successfully doped into carbon nanotubes (CNTs) by a hydrothermal approach in one step, and the synthesized nitrogen‐doped CNT (CNT‐N) materials retained most of the original, excellent characteristics, such as the graphitic structure, tubular morphology, and high surface area, of CNTs. The resultant CNT‐N materials, although containing a relatively low amount of nitrogen doping, exhibited high electrocatalytic ORR activity, comparable to that of 20 wt % Pt/C; long durability; and, more importantly, largely inhibited methanol crossover effect. 相似文献
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Two-dimensional metal-organic frameworks (2D MOFs) inherently consisting of metal entities and ligands are promising single-atom catalysts (SACs) for electrocatalytic chemical reactions. Three 2D Fe-MOFs with NH, O, and S ligands were designed using density functional theory calculations, and their feasibility as SACs for hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and oxygen reduction reaction (ORR) was investigated. The NH, O, and S ligands can be used to control electronic structures and catalysis performance in 2D Fe-MOF monolayers by tuning charge redistribution. The results confirm the Sabatier principle, which states that an ideal catalyst should provide reasonable adsorption energies for all reaction species. The 2D Fe-MOF nanomaterials may render highly-efficient HER, OER, and ORR by tuning the ligands. Therefore, we believe that this study will serve as a guide for developing of 2D MOF-based SACs for water splitting, fuel cells, and metal-air batteries. 相似文献
7.
A Bifunctional Electrocatalyst for Oxygen Evolution and Oxygen Reduction Reactions in Water
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Prof. Dr. Wolfgang Schöfberger Dipl.‐Ing. Felix Faschinger Samir Chattopadhyay Snehadri Bhakta Biswajit Mondal Prof. Dr. Johannes A. A. W. Elemans Prof. Dr. Stefan Müllegger M. Sc. Stefano Tebi Prof. Dr. Reinhold Koch Priv.‐Doz. Dr. Florian Klappenberger Dipl.‐Chem. Mateusz Paszkiewicz Prof. Dr. Johannes V. Barth Dr. Eva Rauls Hazem Aldahhak Prof. Dr. Wolf Gero Schmidt Prof. Dr. Abhishek Dey 《Angewandte Chemie (International ed. in English)》2016,55(7):2350-2355
Oxygen reduction and water oxidation are two key processes in fuel cell applications. The oxidation of water to dioxygen is a 4 H+/4 e? process, while oxygen can be fully reduced to water by a 4 e?/4 H+ process or partially reduced by fewer electrons to reactive oxygen species such as H2O2 and O2?. We demonstrate that a novel manganese corrole complex behaves as a bifunctional catalyst for both the electrocatalytic generation of dioxygen as well as the reduction of dioxygen in aqueous media. Furthermore, our combined kinetic, spectroscopic, and electrochemical study of manganese corroles adsorbed on different electrode materials (down to a submolecular level) reveals mechanistic details of the oxygen evolution and reduction processes. 相似文献
8.
Afridi Zamader Dr. Bertrand Reuillard Dr. Jacques Pécaut Prof. Dr. Laurent Billon Dr. Antoine Bousquet Dr. Gustav Berggren Dr. Vincent Artero 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(69):e202202260
Surface integration of molecular catalysts inspired from the active sites of hydrogenase enzymes represents a promising route towards developing noble metal-free and sustainable technologies for H2 production. Efficient and stable catalyst anchoring is a key aspect to enable this approach. Herein, we report the preparation and electrochemical characterization of an original diironhexacarbonyl complex including two pyrene groups per catalytic unit in order to allow for its smooth integration, through π-interactions, onto multiwalled carbon nanotube-based electrodes. In this configuration, the grafted catalyst could reach turnover numbers for H2 production (TONH2) of up to 4±2×103 within 20 h of bulk electrolysis, operating at neutral pH. Post operando analysis of catalyst functionalized electrodes revealed the degradation of the catalytic unit occurred via loss of the iron carbonyl units, while the anchoring groups and most part of the ligand remained attached onto multiwalled carbon nanotubes. 相似文献
9.
Polyoxometalate and Resin‐Derived P‐Doped Mo2C@N‐Doped Carbon as a Highly Efficient Hydrogen‐Evolution Reaction Catalyst at All pH Values
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Dr. Gang Yan Dr. Xiaojia Feng Dr. Shifa Ullah Khan Dr. Liguang Xiao Wenguang Xi Dr. Huaqiao Tan Dr. Yuanyuan Ma Dr. Lunan Zhang Prof. Yangguang Li 《化学:亚洲杂志》2018,13(2):158-163
A new type of P‐doped Mo2C coated by N‐doped carbon (P‐Mo2C@NC) has been successfully prepared by calcining a mixture of H3[PMo12O40] polyoxometalates (POMs) and urea‐formaldehyde resin under an N2 atmosphere. Urea‐formaldehyde resin not only serves as the carbon source to ensure carbonization but also facilitates the uniform distribution of POM precursors, which efficiently avoid the aggregation of Mo2C particles at high temperatures. TEM analysis revealed that the average diameter of the Mo2C particles was about 10 nm, which is coated by a few‐layer N‐doped carbon sheet. The as‐prepared P‐Mo2C@NC displayed excellent hydrogen‐evolution reaction (HER) performance and long‐term stability in all pH environments. To reach a current density of 10 mA cm?2, only 109, 159, and 83 mV were needed for P‐Mo2C@NC in 0.5 m H2SO4 (pH 0), 0.1 m phosphate buffer (pH 7), and 1 m KOH (pH 14), respectively. This could provide a high‐yield and low‐cost method to prepare uniform nanosized molybdenum carbides with highly efficient and stable HER performance. 相似文献
10.
TiO2 nanotubes were successfully co‐doped with sulfur and Ti3+ states using a facile annealing treatment in H2/H2S gas mixture. The obtained nanotubes were investigated for their photocatalytic performance and characterized by SEM, XRD, XPS, EPR, IPCE, IMPS and Mott‐Schottky measurements. The synthesized co‐doped TiO2 nanotubes show an enhanced photocatalytic hydrogen production rate compared to tubes that were treated only in pure H2 or H2S atmosphere—this without the presence of any co‐catalyst. It was found that sulfur in co‐doped TiO2 exists in the form of S2? and a small quantity of S4+/S6+, which leads to a narrowing of the band gap. However, the enhanced absorption of light in the visible range is not the key reason for the improved photocatalytic performance. We ascribe the enhanced photocatalytic activity to a synergetic effect of S mid‐gap states and disordered Ti3+ defects that facilitate photo generated electron transfer. 相似文献
11.
Xing Wu Prof. Chongjian Tang Prof. Yi Cheng Prof. Xiaobo Min Prof. San Ping Jiang Prof. Shuangyin Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(18):3906-3929
Metal-air batteries (MABs) and reversible fuel cells (RFCs) rely on the bifunctional oxygen catalysts for oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). Finding efficient bifunctional oxygen catalysts is the ultimate goal and it has attracted a great deal of attention. The dilemma is that a good ORR catalyst is not necessarily efficient for OER, and vice versa. Thus, the development of a new type of bifunctional oxygen catalysts should ensure that the catalysts exhibit high activity for both OER and ORR. Composites with multicomponents for active centers supported on highly conductive matrices could be able to meet the challenges and offering new opportunities. In this Review, the evolution of bifunctional catalysts is summarized and discussed aiming to deliver high-performance bifunctional catalysts with low overpotentials. 相似文献
12.
Xuyan Song Yunlu He Bo Wang Sanwen Peng Lin Tong Qiang Liu Jun Yu Haolin Tang 《Molecules (Basel, Switzerland)》2022,27(2)
The development of low platinum loading hydrogen evolution reaction (HER) catalysts with high activity and stability is of great significance to the practical application of hydrogen energy. This paper reports a simple method to synthesize a highly efficient HER catalyst through coating a highly dispersed PtNi alloy on porous nitrogen-doped carbon (MNC) derived from the zeolite imidazolate skeleton. The catalyst is characterized and analyzed by physical characterization methods, such as XRD, SEM, TEM, BET, XPS, and LSV, EIS, it, v-t, etc. The optimized sample exhibits an overpotential of only 26 mV at a current density of 10 mA cm−2, outperforming commercial 20 wt% Pt/C (33 mV). The synthesized catalyst shows a relatively fast HER kinetics as evidenced by the small Tafel slope of 21.5 mV dec−1 due to the small charge transfer resistance, the alloying effect between Pt and Ni, and the interaction between PtNi alloy and carrier. 相似文献
13.
A Versatile Iron–Tannin‐Framework Ink Coating Strategy to Fabricate Biomass‐Derived Iron Carbide/Fe‐N‐Carbon Catalysts for Efficient Oxygen Reduction
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Dr. Jing Wei Yan Liang Yaoxin Hu Biao Kong Prof. George P. Simon Jin Zhang Prof. San Ping Jiang Prof. Huanting Wang 《Angewandte Chemie (International ed. in English)》2016,55(4):1355-1359
The conversion of biomass into valuable carbon composites as efficient non‐precious metal oxygen‐reduction electrocatalysts is attractive for the development of commercially viable polymer electrolyte membrane fuel‐cell technology. Herein, a versatile iron–tannin‐framework ink coating strategy is developed to fabricate cellulose‐derived Fe3C/Fe‐N‐C catalysts using commercial filter paper, tissue, or cotton as a carbon source, an iron–tannin framework as an iron source, and dicyandiamide as a nitrogen source. The oxygen reduction performance of the resultant Fe3C/Fe‐N‐C catalysts shows a high onset potential (i.e. 0.98 V vs the reversible hydrogen electrode (RHE)), and large kinetic current density normalized to both geometric electrode area and mass of catalysts (6.4 mA cm?2 and 32 mA mg?1 at 0.80 V vs RHE) in alkaline condition. This method can even be used to prepare efficient catalysts using waste carbon sources, such as used polyurethane foam. 相似文献
14.
Dr. Wei-Hong Lai Dr. Heng Wang Dr. Lirong Zheng Quan Jiang Dr. Zi-Chao Yan Prof. Lei Wang Dr. Hirofumi Yoshikawa Dr. Daiju Matsumura Prof. Qiao Sun Dr. Yun-Xiao Wang Dr. Qinfen Gu Prof. Jia-Zhao Wang Prof. Hua-Kun Liu Prof. Shu-Lei Chou Prof. Shi-Xue Dou 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(49):22355-22362
Herein, we report a comprehensive strategy to synthesize a full range of single-atom metals on carbon matrix, including V, Mn, Fe, Co, Ni, Cu, Ge, Mo, Ru, Rh, Pd, Ag, In, Sn, W, Ir, Pt, Pb, and Bi. The extensive applications of various SACs are manifested via their ability to electro-catalyze typical hydrogen evolution reactions (HER) and conversion reactions in novel room-temperature sodium sulfur batteries (RT-Na-S). The enhanced performances for these electrochemical reactions arisen from the ability of different single active atoms on local structures to tune their electronic configuration. Significantly, the electrocatalytic behaviors of diverse SACs, assisted by density functional theory calculations, are systematically revealed by in situ synchrotron X-ray diffraction and in situ transmission electronic microscopy, providing a strategic library for the general synthesis and extensive applications of SACs in energy conversion and storage. 相似文献
15.
Vanadium‐Doped WS2 Nanosheets Grown on Carbon Cloth as a Highly Efficient Electrocatalyst for the Hydrogen Evolution Reaction
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《化学:亚洲杂志》2018,13(11):1438-1446
Two‐dimensional transition‐metal dichalcogenides have been widely studied as electrocatalysts for the hydrogen evolution reaction (HER). However, limited active sites and poor conductivity hinder their application. To solve these disadvantages, heteroatom doping has attracted wide attention because it can not only increase the active sites but also affect the intrinsic catalytic properties of the electrocatalyst. Herein, we grew vanadium‐doped WS2 nanosheets on carbon cloth (V‐WS2/CC) as an electrocatalyst for HER under acidic and alkaline conditions. With a proper vanadium doping concentration, the electrochemical surface areas of V0.065‐WS2/CC were 9.6 and 2.6 times as large as that of pure WS2 electrocatalyst under acidic and alkaline conditions, respectively. In addition, the charge‐transfer resistance also decreased with moderate vanadium doping. Based on this, the synthesized vanadium‐doped WS2 nanosheets exhibited good stability with high HER catalytic activity and could reach a current density of 10 mA cm−2 at overpotentials of 148 and 134 mV in 0.5 m H2SO4 and 1 m KOH, respectively. The corresponding Tafel slopes were 71 and 85 mV dec−1. Therefore, our synthesized vanadium‐doped WS2 nanosheets can be a promising electrocatalyst for the production of hydrogen over a wide pH range. 相似文献
16.
Carbon Nanotubes Decorated with CoP Nanocrystals: A Highly Active Non‐Noble‐Metal Nanohybrid Electrocatalyst for Hydrogen Evolution
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Qian Liu Dr. Jingqi Tian Wei Cui Dr. Ping Jiang Ningyan Cheng Prof. Abdullah M. Asiri Prof. Xuping Sun 《Angewandte Chemie (International ed. in English)》2014,53(26):6710-6714
The development of effective and inexpensive hydrogen evolution reaction (HER) electrocatalysts for future renewable energy systems is highly desired. The strongly acidic conditions in proton exchange membranes create a need for acid‐stable HER catalysts. A nanohybrid that consists of carbon nanotubes decorated with CoP nanocrystals (CoP/CNT) was prepared by the low‐temperature phosphidation of a Co3O4/CNT precursor. As a novel non‐noble‐metal HER catalyst operating in acidic electrolytes, the nanohybrid exhibits an onset overpotential of as low as 40 mV, a Tafel slope of 54 mV dec?1, an exchange current density of 0.13 mA cm?2, and a Faradaic efficiency of nearly 100 %. This catalyst maintains its catalytic activity for at least 18 hours and only requires overpotentials of 70 and 122 mV to attain current densities of 2 and 10 mA cm?2, respectively. 相似文献
17.
Xu‐Bing Li Chen‐Ho Tung Li‐Zhu Wu 《Angewandte Chemie (International ed. in English)》2019,58(32):10804-10811
Light‐driven multielectron redox reactions (e.g., hydrogen (H2) evolution, CO2 reduction) have recently appeared at the front of solar‐to‐fuel conversion. In this Minireview, we focus on the recent advances in establishing semiconductor quantum dot (QD) assemblies to enhance the efficiencies of these light‐driven multielectron reduction reactions. Four models of QD assembly are established to promote the sluggish kinetics of multielectron transfer from QDs to cocatalysts, thus leading to an enhanced activity of solar H2 evolution or CO2 reduction. We also forecast the potential applications of QD assemblies in other multielectron redox reactions, such as nitrogen (N2) fixation and oxygen (O2) evolution from H2O. 相似文献
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Facile Synthesis of Quasi‐One‐Dimensional Au/PtAu Heterojunction Nanotubes and Their Application as Catalysts in an Oxygen‐Reduction Reaction
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Kai Cai Jiawei Liu Huan Zhang Zhao Huang Dr. Zhicheng Lu Mohamed F. Foda Tingting Li Prof. Heyou Han 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(20):7556-7561
An intermediate‐template‐directed method has been developed for the synthesis of quasi‐one‐dimensional Au/PtAu heterojunction nanotubes by the heterogeneous nucleation and growth of Au on Te/Pt core–shell nanostructures in aqueous solution. The synthesized porous Au/PtAu bimetallic nanotubes (PABNTs) consist of porous tubular framework and attached Au nanoparticles (AuNPs). The reaction intermediates played an important role in the preparation, which fabricated the framework and provided a localized reducing agent for the reduction of the Au and Pt precursors. The Pt7Au PABNTs showed higher electrocatalytic activity and durability in the oxygen‐reduction reaction (ORR) in 0.1 M HClO4 than porous Pt nanotubes (PtNTs) and commercially available Pt/C. The mass activity of PABNTs was 218 % that of commercial Pt/C after an accelerated durability test. This study demonstrates the potential of PABNTs as highly efficient electrocatalysts. In addition, this method provides a facile strategy for the synthesis of desirable hetero‐nanostructures with controlled size and shape by utilizing an intermediate template. 相似文献
20.
Carbon Nanotubes/Heteroatom‐Doped Carbon Core–Sheath Nanostructures as Highly Active,Metal‐Free Oxygen Reduction Electrocatalysts for Alkaline Fuel Cells
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Young Jin Sa Dr. Chiyoung Park Dr. Hu Young Jeong Dr. Seok‐Hee Park Prof. Zonghoon Lee Prof. Kyoung Taek Kim Dr. Gu‐Gon Park Prof. Sang Hoon Joo 《Angewandte Chemie (International ed. in English)》2014,53(16):4102-4106
A facile, scalable route to new nanocomposites that are based on carbon nanotubes/heteroatom‐doped carbon (CNT/HDC) core–sheath nanostructures is reported. These nanostructures were prepared by the adsorption of heteroatom‐containing ionic liquids on the walls of CNTs, followed by carbonization. The design of the CNT/HDC composite allows for combining the electrical conductivity of the CNTs with the catalytic activity of the heteroatom‐containing HDC sheath layers. The CNT/HDC nanostructures are highly active electrocatalysts for the oxygen reduction reaction and displayed one of the best performances among heteroatom‐doped nanocarbon catalysts in terms of half‐wave potential and kinetic current density. The four‐electron selectivity and the exchange current density of the CNT/HDC nanostructures are comparable with those of a Pt/C catalyst, and the CNT/HDC composites were superior to Pt/C in terms of long‐term durability and poison tolerance. Furthermore, an alkaline fuel cell that employs a CNT/HDC nanostructure as the cathode catalyst shows very high current and power densities, which sheds light on the practical applicability of these new nanocomposites. 相似文献