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Synergy of Fe-N4 and non-coordinated boron atoms for highly selective oxidation of amine into nitrile 被引量:3
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作者 Hong-Hui Wang Li-Bing Lv +5 位作者 Shi-Nan Zhang Hui Su Guang-Yao Zhai Wei-Wei Lei Xin-Hao Li Jie-Sheng Chen 《Nano Research》 SCIE EI CAS CSCD 2020年第8期2079-2084,共6页
The rational design of highly active and stable atomically dispersed M-X4(M=Fe,Co,Ni,etc.,X=C,N)-based catalysts holds promises for wide application in almost all realms of catalysis.Despite great effort in the constr... The rational design of highly active and stable atomically dispersed M-X4(M=Fe,Co,Ni,etc.,X=C,N)-based catalysts holds promises for wide application in almost all realms of catalysis.Despite great effort in the construction of specific M-X4 centers,the possible effect of non-coordinated heteroatoms on the catalytic activity of metal centers has been rarely explored.Herein,we develop a new type of M-X4 catalyst composed of Fe-N4 centers and non-coordinated B heteroatoms(FeNC+B)and find the key role of non-coordinated B adjacent to Fe-N4 centers in tailoring their electron density and final catalytic selectivity.The experimental and theoretical results demonstrated that non-coordinated boron atoms could decrease the electron density of Fe-N4 centers to a suitable level and thus boost the selective production of nitriles from amine oxidation by depressing the formation of imines due to the flattened energy barrier of the reversible conversion of imines back to amines.As a reusable heterocatalyst,the state-of-the-art FeNC+B catalyst provides a turn-over frequency(TOF)value of 21.6 molbenzonitrile·molFe^−1·h^−1(100℃),outpacing that of bench-marked nonnoble-metal-based homogeneous catalyst by a factor of 3.4. 展开更多
关键词 atomically dispersed catalyst fe-n4 non-coordinated boron selective oxidation NITRILE
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Controllable synthesis of Fe–N4 species for acidic oxygen reduction 被引量:6
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作者 Xuecheng Yan Yi Jia +5 位作者 Kang Wang Zhao Jin Chung-Li Dong Yu-Cheng Huang Jun Chen Xiangdong Yao 《Carbon Energy》 CAS 2020年第3期452-460,共9页
Controllable design and synthesis of catalysts with the target active sites are extremely important for their applications such as for the oxygen reduction reaction(ORR)in fuel cells.However,the controllably synthesiz... Controllable design and synthesis of catalysts with the target active sites are extremely important for their applications such as for the oxygen reduction reaction(ORR)in fuel cells.However,the controllably synthesizing electrocatalysts with a single type of active site still remains a grand challenge.In this study,we developed a facile and scalable method for fabricating highly efficient ORR electrocatalysts with sole atomic Fe-N4 species as the active site.Herein,the use of cost-effective highly porous carbon as the support not only could avoid the aggregation of the atomic Fe species but also a feasible approach to reduce the catalyst cost.The obtained atomic Fe-N4 in activated carbon(aFe@AC)shows excellent ORR activity.Its half-wave potential is 59 mV more negative but 47 mV more positive than that of the commercial Pt/C in acidic and alkaline electrolytes,respectively.The full cell performance test results show that the aFe@AC sample is a promising candidate for direct methanol fuel cells.This study provides a general method to prepare catalysts with a certain type of active site and definite numbers. 展开更多
关键词 atomic fe-n4 site controllable synthesis fuel cells oxygen reduction reaction
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Multiscale structural engineering of atomically dispersed FeN4 electrocatalyst for proton exchange membrane fuel cells 被引量:1
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作者 Ruguang Wang Yuanyuan Yang +4 位作者 Yang Zhao Liujing Yang Pengfei Yin Jing Mao Tao Ling 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第7期629-635,共7页
Atomically dispersed iron-nitrogen-carbon(Fe-N-C) catalysts have emerged as the most promising alternative to the expensive Pt-based catalysts for the oxygen reduction reaction(ORR) in proton exchange membrane fuel ce... Atomically dispersed iron-nitrogen-carbon(Fe-N-C) catalysts have emerged as the most promising alternative to the expensive Pt-based catalysts for the oxygen reduction reaction(ORR) in proton exchange membrane fuel cells(PEMFCs),however suffer from low site density of active Fe-N4 moiety and limited mass transport during the catalytic reaction.To address these challenges,we report a three-dimensional(3D) metal-organic frameworks(MOF)-derived Fe-N-C single-atom catalyst.In this well-designed Fe-N-C catalyst,the micro-scale interconnected skeleton,the nano-scale ordered pores and the atomic-scale abundant carbon edge defects inside the skeleton significantly enhance the site density of active Fe-N4 moiety,thus improving the Fe utilization in the final catalyst.Moreover,the combination of the above mentioned micro-and nano-scale structures greatly facilitates the mass transport in the 3D Fe-N-C catalyst.Therefore,the multiscale engineered Fe-N-C single-atom catalyst achieves excellent ORR performance under acidic condition and affords a significantly enhanced current density and power density in PEMFC.Our findings may open new opportunities for the rational design of FeN-C catalysts through multiscale structural engineering. 展开更多
关键词 Fe–N–C catalyst fe-n4 Proton exchange membrane fuel cells Oxygen reduction reaction Single-atom catalyst
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氮化硅铁对铝碳质炮泥性能影响的研究 被引量:6
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作者 周永平 唐丽霞 付文亮 《河南冶金》 2013年第6期17-19,共3页
以白刚玉、焦粉及焦油为主要原料,制备了铝碳质炮泥。通过考察氮化硅铁在炮泥中的反应性能,研究氮化硅铁加入量对其强度和抗渣侵性能的影响,利用X射线衍射分析炮泥的相组成,采用扫描电子显微镜观察其微观组织结构。研究结果表明,随着氮... 以白刚玉、焦粉及焦油为主要原料,制备了铝碳质炮泥。通过考察氮化硅铁在炮泥中的反应性能,研究氮化硅铁加入量对其强度和抗渣侵性能的影响,利用X射线衍射分析炮泥的相组成,采用扫描电子显微镜观察其微观组织结构。研究结果表明,随着氮化硅铁加入量的增加,炮泥的强度和抗渣侵性能都先增加后减小;当其加入量为10%时,可以制备出强度高、抗渣侵性能好的铝碳质炮泥。 展开更多
关键词 氮化硅铁 铝碳质炮泥 强度 抗渣侵性能
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氮化硅铁对无水炮泥性能影响的研究 被引量:3
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作者 李军希 《河南冶金》 2014年第1期8-12,共5页
根据无水炮泥的基本配合比,分别用不同比例的氮化硅铁替代其中的刚玉作基质料,在埋炭条件下经110℃×24 h,900℃×2 h处理,以及在通氮气条件下经1500℃×2 h煅烧后,分别检测和分析了试样的物理性能。结果显示,试样的烘干强... 根据无水炮泥的基本配合比,分别用不同比例的氮化硅铁替代其中的刚玉作基质料,在埋炭条件下经110℃×24 h,900℃×2 h处理,以及在通氮气条件下经1500℃×2 h煅烧后,分别检测和分析了试样的物理性能。结果显示,试样的烘干强度最大,中温强度最低,高温强度介于两者之间。随着氮化硅铁含量从4%递增到12%,试样经过1500℃高温处理后,其常温耐压强度和抗折强度均呈递增趋势,当氮化硅铁含量为10%时达到最大值,体积密度则呈下降趋势,同时试样的抗渣渗透性能和抗渣侵蚀性能得到了提高,试样的钻孔开口时间逐渐缩短。 展开更多
关键词 高炉 无水炮泥 氮化硅铁
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后合成静电吸附辅助制备高效Fe-N-C单原子氧还原催化剂用于锌-空气电池 被引量:4
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作者 李乐 李娜 +5 位作者 夏佳伟 邢浩然 阿里夫·默罕默德 赵宜涛 何光裕 陈海群 《Science China Materials》 SCIE EI CAS CSCD 2023年第3期992-1001,共10页
设计和制备高效的非铂族催化剂对锌-空气电池的大规模应用至关重要.本文采用简单的后合成静电吸附策略制备了Fe-N-C单原子催化剂(Fe-SA/N-C).其中,Fe原子与相邻的氮原子形成Fe-N4活性位点并锚定在三维多孔碳上.该催化剂在0.1 mol L^(-1)... 设计和制备高效的非铂族催化剂对锌-空气电池的大规模应用至关重要.本文采用简单的后合成静电吸附策略制备了Fe-N-C单原子催化剂(Fe-SA/N-C).其中,Fe原子与相邻的氮原子形成Fe-N4活性位点并锚定在三维多孔碳上.该催化剂在0.1 mol L^(-1)KOH (E_(1/2)=0.92 V)和0.5 mol L^(-1)H_(2)SO_(4)(E_(1/2)=0.77 V)中均表现出优异的氧化还原活性,性能优于商业Pt/C催化剂(0.1 mol L^(-1)KOH,E_(1/2)=0.85 V;0.5 mol L^(-1)H_(2)SO_(4),E_(1/2)=0.79 V).此外,以Fe-SA/N-C作为阴极催化剂自组装的液体锌-空气电池具有优异的放电比容量和峰值功率密度,优于商业Pt/C催化剂.密度泛函理论计算结果表明,石墨化氮掺杂的Fe-N4位点能有效提高ORR中间产物的活化程度,降低速率决定步骤的能垒.本工作对非铂族催化剂的实验制备和理论研究提出了新的见解,为锌-空气电池中使用的非铂族催化剂的合理设计提供了一般策略. 展开更多
关键词 密度泛函理论计算 单原子催化剂 PT/C催化剂 静电吸附 氧化还原活性 能垒 活化程度 阴极催化剂
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Yolk-shell FeCu/NC electrocatalyst boosting high-performance zinc-air battery
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作者 Chen Liang Tianyu Zhang +4 位作者 Shilun Sun Aijuan Han Zenghui Qiu Haijun Xu Junfeng Liu 《Nano Research》 SCIE EI CSCD 2024年第9期7918-7925,共8页
Iron-nitrogen-carbon single-atom catalysts(Fe-N-C SACs)are widely acknowledged for their effective oxygen reduction activity,however,their activity requires further enhancement.Meanwhile,additional structural optimiza... Iron-nitrogen-carbon single-atom catalysts(Fe-N-C SACs)are widely acknowledged for their effective oxygen reduction activity,however,their activity requires further enhancement.Meanwhile,additional structural optimization is necessary to enhance mass transport and achieve higher power density in practical applications.Herein,using ZIF-8 as a template,we synthesized yolk-shell catalysts featuring complex sites of Fe single atoms and Cu nanoclusters(y-FeCu/NC)via partial etching and liquid-phase loading.The synthesized y-FeCu/NC catalyst exhibits high specific surface area and mesoporous volume.Combined with the advantages of highly active sites and yolk-shell structure,the y-FeCu/NC catalyst demonstrated outstanding catalytic performance in the oxygen reduction reaction,achieving a half-wave potential(E_(1/2))of 0.97 V in 0.1 M KOH.As a practical energy device,Zn-air battery(ZAB)assembled with y-FeCu/NC catalyst achieved a remarkable power density of 356.3 mW·cm^(-2),representing an improvement of approximately 28.5%compared to its solid FeCu/NC counterpart.Furthermore,it showcased impressive stability,surpassing all control samples. 展开更多
关键词 atomic fe-n4 sites Cu nanoclusters yolk-shell structure oxygen reduction reaction zinc-air battery
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Phosphorus-doped iron-nitrogen-carbon catalyst with pentacoordinated single atom sites for efficient oxygen reduction
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作者 Lili Fan Xiaofei Wei +7 位作者 Xuting Li Zhanning Liu Mengfei Li Shuo Liu Zixi Kang Fangna Dai Xiaoqing Lu Daofeng Sun 《Nano Research》 SCIE EI CSCD 2023年第2期1810-1819,共10页
Single-atomic Fe-N4 is the well-acknowledged active site in iron-nitrogen-carbon(Fe-N-C)material for oxygen reduction reaction(ORR).The adjusting of the electronic distribution of Fe-N4 is promising for further enhanc... Single-atomic Fe-N4 is the well-acknowledged active site in iron-nitrogen-carbon(Fe-N-C)material for oxygen reduction reaction(ORR).The adjusting of the electronic distribution of Fe-N4 is promising for further enhancing the performance of the Fe-N-C catalyst.Herein,a phosphorus(P)-doped Fe-N-C catalyst with penta-coordinated single atom sites(FeNPC)is reported for efficient oxygen reduction.Fe K-edge X-ray absorption spectroscopy(XAS)verifies the coordination environment of single Fe atom,while density functional theory(DFT)calculations reveal that the penta-coordination and neighboring doped P atoms can simultaneously change the electronic distribution of Fe-N_(4)and its adsorption strength of key intermediates,reducing the reactionfree energy of the potential-limiting step.Electrochemical tests validate the remarkable intrinsic ORR activity of FeNPC in alkaline media(a half-wave potential(E_(1/2))of 0.904 V vs.reversible hydrogen electrode(RHE)and limited current density(JL)of 6.23 mA·cm^(−2))and an enhanced ORR performance in neutral(E_(1/2)=0.751 V,J_(L)=5.27 mA·cm^(−2))and acidic media(E_(1/2)=0.735 V,JL=5.82 mA·cm^(−2))with excellent stability,highlighting the benefits of optimizing the local environment of singleatomic Fe-N4. 展开更多
关键词 fe-n-C fe-n4 penta-coordination oxygen reduction reaction P-DOPING
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