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Journal of Energy Chemistry 2021年第2期30卷 49-55,I0002页

作者： Xuewan Wang Xiuan Xi Ge Huo Chenyu Xu Pengfei Sui Renfei Feng Xian-Zhu Fu Jing-Li Luo College of Materials Science and Engineering Shenzhen UniversityShenzhen 518060GuangdongChina Department of Chemical and Materials Engineering University of AlbertaEdmonton T6G 1H9AlbertaCanada Canadian Light Source Saskatoon S7N 2V3SaskatchewanCanada

Biomolecules with a broad range of structure and heteroatom-containing groups offer a great opportunity for rational design of promising electrocatalysts via versatile chemistry.In this study,uniform folic acid-Co nanotubes(FA-Co NTs) were hydrothermally prepared as sacrificial templates for highly porous Co and N co-doped carbon nanotubes(Co-N/CNTs) with well-controlled size and morphology.The formation mechanism of FA-Co NTs was investigated and FA-Co-hydrazine coordination interaction together with the H-bond interaction between FA molecules was characterized to be the driving force for growth of one-dimensional nanotubes.Such distinct metal-ligand interaction afforded the resultant CNTs rich Co-N_x sites,hierarchically porous structure and Co nanoparticle-embedded conductive network,thus an overall good electrocatalytic activity for oxygen reduction.Electrochemical tests showed that Co-N/CNTs-900 promoted an efficient 4 e ORR process with an onset potential of 0.908 V vs.RHE,a limiting current density of 5.66 mA cm^(-2) at 0.6 V and a H_2 O_2 yield lower than 5%,comparable to that of 20%Pt/C catalyst.Moreover,the catalyst revealed very high stability upon continuous operation and remarkable tolerance to methanol.

关键词： Folic acid Metal–organic nanotube Carbon nanotube In situ doping oxygen reduction

Porphyrin-like Fe-N4 sites with sulfur adjustment on hierarchical porous carbon for different rate-determining steps in oxygen reduction reaction

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Nano Research 2018年第12期11卷 6260-6269页

作者： Konglin Wu Xin Chen Shoujie Liu Yuan Pan Weng-Chon Cheong Wei Zhu Xing Cao Rongan Shen Wenxing Chen Jun LUO Wensheng Yan Lirong Zheng Zheng Chen Dingsheng Wang Qing Peng Chen Chen Yadong Li Department ofChemistry Tsinghua UniversityBeijing 100084China Beijing Key Laboratory for Science and Application of Functional Molecular and Crystalline Materials Department of ChemistryUniversity of Science and Technology BeijingBeijing 100083China College of Chemistry and Materials Science Key Laboratory of Functional Molecular Solidsthe Ministry of EducationAnhui Normal UniversityWuhu 241002China Center for Electron Microscopy Tianjin University of TechnologyTianjin 300384China NationaISynchrotron Radiation Laboratory (NSRL) University of Science and Technology of ChinaHefei 230029China Beijing Synchrotron Radiation Facility (NSRF) Institute of High Energy PhysicsChinese Academy of ScienceBeijing 100049China

We developed a strategy based on coordination polymer to synthesize singleatom site Fe/N and S-codoped hierarchical porous carbon (Fe1/N,S-PC). The as-obtained Fe1/N,S-PC exhibited superior oxygen reduction reaction (ORR) performance with a half-wave potential (E1/2, 0.904 V vs. RHE) that was better than that of commercial Pt/C (E1/2, 0.86 V vs. RHE), single-atom site Fe/N-doped hierarchical porous carbon (Fe1/N-PC) without S-doped (E1/2, 0.85 V vs. RHE), and many other nonprecious metal catalysts in alkaline medium. Moreover, the Fe1/N,S-PC revealed high methanol tolerance and firm stability. The excellent electrocatalytic activity of Fe1/N,S-PC is attributed to the synergistic effects from the atomically dispersed porphyrin-like Fe-N4 active sites, the heteroatom codoping (N and S), and the hierarchical porous structure in the carbon materials. The calculation based on density functional theory further indicates that the catalytic performance of Fe1/N,S-PC is better than that of Fe1/N-PC owing to the sulfur doping that yielded different rate-determining steps.

关键词： single-atom catalyst heteroatom codoping porous materials oxygen reduction electrocatalysis

Accelerated oxygen reduction on Fe/N/C catalysts derived from precisely-designed ZIF precursors

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Nano Research 2020年第9期13卷 2420-2426页

作者： Ergui Luo Chen Wang Yang Li Xian Wang Liyuan Gong Tuo Zhao Zhao Jin Junjie Ge Changpeng Liu Wei Xing Laboratory of Advanced Power Sources Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

Fe/N/C material is the most competitive alternative to precious-metal catalysts for oxygen reduction.In view of the present consensus on active centers,further effort is directed at maximizing the density of single Fe atoms.Here,the imperfections in commonly used doping strategy of Fe for the synthesis of zeolitic imidazolateframework(ZIF)-derived Fe/N/C catalysts are revealed.More importantly,a strikingly improved catalyst is obtained by a‘second pyrolysis’method and delivers a half-wave potential of 0.825 V(vs.RHE)in acidic media.The strong confinement effect of carbonaceous host accounts for the formation of dense single-atom sites and thus the high activity.Our findings will potentially facilitate future improvement of M/N/C catalysts.

关键词： electrocatalysis fuel cells oxygen reduction Fe/N/C single-atom catalysts

Coupled intramolecular/heterointerfacial electron transfer in polyelectrolyte-shielded Iso-type black phosphorus hetero-structure boosts oxygen reduction kinetics

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Journal of Energy Chemistry 2021年第12期30卷 468-476,I0011页

作者： Zhongke Yuan Jing Li Zhengsong Fang Meijia Yang Kancheng Mai Dingshan Yu Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education Key Laboratory of High Performance Polymer-based Composites of Guangdong ProvinceSchool of ChemistrySun Yat-sen UniversityGuangzhou 510275GuangdongChina

Searching new structured black phosphorus(BP)and exploring intriguing functions and applications have become a hot topic so far.Here,we introduce a novel Iso-type black phosphorus heterostructure guided by first principle calculation,which features unique heterointerface and electronic coupling interaction via stacking assembly of exfoliated black phosphorus(EBP)and amine-functionalized EBP(N-EBP).Inspired by the theoretical results,we constructed the Iso-type heterostructure comprising of ultrathin exfoliated few-layered EBP and N-EBP,both of which were derived from identical bulk BP.The purposive amine-functionalization not only creates positively-charged P atoms on N-EBP as effective active sites via N-induced intramolecular electron transfer(IET)but also endows N-EBP with lower work function relative to EBP,while the unique EBP/N-EBP Iso-type heterostructure engenders directional heterointerfacial electron transfer(HET).The coupled IET/HET effects optimize the charge redistribution to afford favorable O_(2)adsorption.In this case,our unique strategy for the first time exploits the inherent catalytic capability of BP toward the oxygen reduction reaction(ORR)and enables the first use of BP as metal-free ORR catalysts for Zn-air cells.The newly-designed heterostructure facilitates a 4-e^(-)transfer ORR relative to inactive EBP or N-EBP.Importantly,the polymer-shielded heterostructure acts as efficient air electrodes to endow a primary Zn-air cell with high stability,large capacity and high energy density—superior to the commercial Pt/C-enabled cell.This study as the first report on metal-free BP-based ORR catalysts and air electrodes not only extends BP's application scopes but also renders new insight toward design of electronically-coupled superstructures for energy-related applications.

关键词： Black phosphorus Iso-type heterostructure Intramolecular electron transfer Heterointerfacial electron transfer oxygen reduction

Scalable fabrication and active site identification of MOF shell-derived nitrogen-doped carbon hollow frameworks for oxygen reduction

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Journal of Materials Science & Technology 2021年第7期66卷 186-192页

作者： Jiashen Meng Ziang Liu Xiong Liu Wei Yang Lianzhou Wang Yan Li Yuan-Cheng Cao Xingcai Zhang Liqiang Mai State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan430070China Nanomaterials Centre School of Chemical Engineering and Australian Institute for Bioengineering and NanotechnologyThe University of QueenslandSt LuciaQLD4072Australia Shenzhen Power Supply Col.Ltd. Shenzhen CityChina State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan430074China John A.Paulson School of Engineering and Applied Sciences Harvard UniversityCambridgeMA02138United States

Nitrogen-doped carbon materials as promising oxygen reduction reaction(ORR) electrocatalysts attract great interest in fuel cells and metal-air batteries because of their relatively high activity, high surface area, high conductivity and low cost. To maximize their catalytic efficiency, rational design of efficient electrocatalysts with rich exposed active sites is highly desired. Besides, due to the complexity of nitrogen species, the identification of active nitrogen sites for ORR remains challenging. Herein, we develop a facile and scalable template method to construct high-concentration nitrogen-doped carbon hollow frameworks(NC), and reveal the effect of different nitrogen species on theirORRactivity on basis of experimental analysis and theoretical calculations. The formation mechanism is clearly revealed, including low-pressure vapor superassembly of thin zeolitic imidazolate framework(ZIF-8) shell on ZnO templates,in situ carbonization and template removal. The obtained NC-800 displays better ORR activity compared with other NC-700 and NC-900 samples. Our results indicate that the superior ORR activity of NC-800 is mainly attributed to its content balance of three nitrogen species. The graphitic N and pyrrolic N sites are responsible for lowering the working function, while the pyridinic N and pyrrolic N sites as possible active sites are beneficial for increasing the density of states.

关键词： MOF shell Nitrogen-doped carbon Hollow framework oxygen reduction Active nitrogen sites

Identifying the Zn-Co binary as a robust bifunctional electrocatalyst in oxygen reduction and evolution reactions via shifting the apexes of the volcano plot

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Journal of Energy Chemistry 2021年第4期30卷 162-168页

作者： Jing Wang Rui Xu Yuling Sun Qian Liu Meirong Xia Yan Li Faming Gao Yufeng Zhao John S.Tse Key Laboratory of Applied Chemistry Hebei Key Laboratory of Heavy Metal Deep-Remediation in Water and Resource ReuseSchool of Environmental and Chemistry EngineeringYanshan UniversityNo.438Hebei St(W)Qinhuangdao 066004HebeiChina Institute of Sustainable Energy/College of Science Shanghai UniversityShanghai 200444China Department of Physics and Engineering Physics University of SaskatchewanSaskatoonSK S7N 5B2Canada

The performance of an electrocatalyst is closely correlated with the binding strength of key oxygencontaining intermediates,i.e.,*OOH,*O and*OH,in the oxygen reduction reaction(ORR)and oxygen evolution reaction(OER).Facile strategies to achieve favorable binding strength of these oxygen-containing species are urgently demanded,yet it still remains great challenges.Herein,the Zn-Co bimetallic isolation,which serves as an ideal model,is studied systematically by the density functional theory(DFT).Reaction activity volcano plots are built from 48 models,among them the ZnCoN6-gra(I)configuration is confirmed to be the most stable,featured of the strongest interaction with the oxygen-containing species.Optimal △G*O(free energy change of an atomic oxygen containing intermediate)is facilitated,which effectively drifts the volcano peaks of ORR and OER closer to each other,enabling promising bifunctional catalyst.Moreover,the small overpotential in the simulation of protonation and oxidation by hydroxy groups rationalizes the durability of the catalyst in both acid and alkaline media.

关键词： Single-atom catalyst oxygen reduction Electrocatalysis DFT Reaction volcano

Rapid low-temperature synthesis of perovskite/carbon nanocomposites as superior electrocatalysts for oxygen reduction in Zn-air batteries

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Nano Research 2018年第6期11卷 3282-3293页

作者： Zhenhua Yan Hongming Sun Xiang Chen Xiaorui Fu Chengcheng Chen Fangyi Cheng Jun Chen Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) College of Chemistry Nankai University Tianjin 300071 China Collaborative Innovation Center of Chemical Science and Engineering Nankai University Tianjin 30007 I China

The conventional ceramic synthesis of perovskite oxides involves extended high-temperature annealing in air and is unfavorable to the in situ hybridization of the conductive agent, thus resulting in large particle sizes, low surface area and limited electrochemical activities. Here we report a rapid gel auto-combustion approach for the synthesis of a perovskite/carbon hybrid at a low temperature of 180℃. The energy-saving synthetic strategy allows the formation of small and homogeneously dispersed LaxMnO3±6/C nanocomposites. Remarkably, the synthesized La0.99MnO3.03/C nanocomposite exhibits comparable oxygen reduction reaction （ORR） activity （with onset and peak potentials of 0.97 and 0.88 V, respectively） to the benchmark Pt/C due to the facilitated charge transfer, optimal eg electron filling of Mn, and coupled C-O-Mn bonding. Furthermore, the nanocomposite efficiently catalyzes a Zn-air battery that delivers a peak power density of 430 mW·cm^-2, an energy density of 837 W·h·kgzn^-1 and 340 h stability at a current rate of 10 mA·cm^-2.

关键词： perovskite oxide nanocomposite electrocatalysis oxygen reduction Zn-air batteries

Effect of supporting materials on the electrocatalytic activity, stability and selectivity of noble metal-based catalysts for oxygen reduction and hydrogen evolution reactions

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Progress in Natural Science:Materials International 2020年第3期30卷 289-297页

作者： Aleksei Chalgin Chengyi Song Peng Tao Wen Shang Tao Deng Jianbo Wu State Key Laboratory of Metal Matrix Composites School of Materials Science and Engineering Shanghai Jiao Tong University Center of Hydrogen Science Shanghai Jiao Tong University Materials Genome Initiative Center Shanghai Jiao Tong University

Carbonaceous and alternative supporting materials for platinum(Pt) and palladium(Pd) have been explored for the cathodic electrocatalysis in low-temperature fuel cells. Pd and Pt are widely used for catalysis owing to their remarkable electrocatalytic activity toward water splitting and fuel cell reactions. Supporting materials play a paramount role in defining electrocatalytic properties such as durability, selectivity, and activity. The conventional supporting material such as carbon black is unable to fit all the requirements under the severe operating conditions of fuel cells due to its poor corrosion resistance and limited mass transport of fuels to active catalyst sites. Nowadays the scientific research is being concentrated on devising different altered carbonic and carbonfree supporting materials for catalysts to improve the catalytic activity, stability, and selectivity of noble metal electrocatalysts. Lately, Pt, Pd and their alloy catalysts supported on modified carbonaceous and carbon-free materials have attracted solid interest owing to their prominent characteristics contributing to the remarkable fuel cell efficacy. Therefore, it is reasonable to explore this theme, regarding a variety of supporting materials,their advantages, drawbacks and future perspectives. In this mini-review, we selectively summarize recent advancements on several types of key supporting materials: carbon(graphene, carbon nanotubes, mesoporous carbon, and doped carbon nanostructures), non-carbon(transition metals oxides, borides, nitrides, and carbides)and hybrid nanocomposites.

关键词： Electrocatalyst Supporting material Fuel cell oxygen reduction Hydrogen evolution

Nitrogen-doped Porous Carbon Derived from Surface-attached Polymer Layers for oxygen reduction Reaction under Acidic Conditions

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Journal of Wuhan University of Technology(Materials Science) 2017年第6期32卷 1287-1292页

作者：潘向川 BOAKYE Felix Ofori LIU Kai 张海宁 State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan 430070 China

We reported the synthesis of nitrogen-doped carbon using surface-attached polyelectrolyte layers as precursors. The synthesized material has a large surface area of 800 m^2·g^-1 with uniformed pore distribution. Benefitfed from the high pyridinic nitrogen content, the synthesized nitrogen-doped porous carbon material exhibits promising electrocatalytic activity toward oxygen reduction reactions in acidic medium and very high stability against continuous cyclic voltammetry scans. The experimental results demonstrate that surface-attached polyelectrolyte layers are promising carbon and nitrogen sources for the formation of heteroatom-doped porous carbon materials.

关键词： mesoporous materials polyelectrolyte carbon surface-attachment oxygen reduction stability

Interface engineering of Co_(3)O_(4)-SmMn_(2)O_(5) nanosheets for efficient oxygen reduction electrocatalysis

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Frontiers of Materials Science 2021年第4期15卷 567-576页

作者： Ying WANG Fan LIU Hongjie YUAN Tianjun HU Key Laboratory of Magnetic Molecules&Magnetic Information Materials(Ministry of Education) School of Chemical and Material ScienceShanxi Normal UniversityTaiyuan 030006China

Interface engineering is an efficient strategy to modify electronic structure and further improve electrocatalytic activity.Herein,crystalline/amorphous heterostructured Co3O4-SmMn2O5 nanosheets(Co3O4-SMO NSs)have been synthesized by coupling of SMO(electron acceptor)with higher Fermi-level Co3O4(electron donor),via a one-step hydrothermal method followed by calcination.The resulting Co3O4-SMO NSs display higher half-wave potential and specific activity than those of pure SMO or Co3O4.In addition,Co3O4-SMO NSs exhibit superior stability and methanol tolerance.The crystalline/amorphous heterostructure and the electron interaction between SMO and Co3O4 result in interfacial charge transfer.This leads to more active valence states and more oxygen vacancies,optimizing the adsorption energy of O species and expediting electron migration,thus boosting oxygen reduction reaction(ORR)catalytic performance.This study provides a promising strategy to design efficient ORR electrocatalysts by interfacial engineering.

关键词： mullite oxide interfacial engineering work function oxygen reduction