期刊文献+
共找到660篇文章
< 1 2 33 >
每页显示 20 50 100
Ordering Degree Regulation of Pt_(2)NiCo Intermetallics for Efficient Oxygen Reduction Reaction
1
作者 Chen-Hao Zhang Han-Yu Hu +3 位作者 Jun-Hao Yang Qian Zhang Chang Yang De-Li Wang 《电化学(中英文)》 北大核心 2025年第4期12-23,共12页
Alloying transition metals with Pt is an effective strategy for optimizing Pt-based catalysts toward the oxygen reduction reaction(ORR).Atomic ordered intermetallic compounds(IMC)provide unique electronic and geometri... Alloying transition metals with Pt is an effective strategy for optimizing Pt-based catalysts toward the oxygen reduction reaction(ORR).Atomic ordered intermetallic compounds(IMC)provide unique electronic and geometrical effects as well as stronger intermetallic interactions due to the ordered arrangement of metal atoms,thus exhibiting superior electrocata-lytic activity and durability.However,quantitatively analyzing the ordering degree of IMC and exploring the correlation between the ordering degree and ORR activity remains extremely challenging.Herein,a series of ternary Pt_(2)NiCo interme-tallic catalysts(o-Pt_(2)NiCo)with different ordering degree were synthesized by annealing temperature modulation.Among them,the o-Pt_(2)NiCo which annealed at 800℃for two hours exhibits the highest ordering degree and the optimal ORR ac-tivity,which the mass activity of o-Pt_(2)NiCo is 1.8 times and 2.8 times higher than that of disordered Pt_(2)NiCo alloy and Pt/C.Furthermore,the o-Pt_(2)NiCo still maintains 70.8%mass activity after 30,000 potential cycles.Additionally,the ORR activity test results for Pt_(2)NiCo IMC with different ordering degree also provide a positive correlation between the ordering degree and ORR activity.This work provides a prospective design direction for ternary Pt-based electrocatalysts. 展开更多
关键词 Fuel cell oxygen reduction reaction ELECTROCATALYSIS Intermetallic compound Ordering degree
在线阅读 下载PDF
De novo-design of highly exposed Co−N−C single-atom catalyst for oxygen reduction reaction
2
作者 ZHOU Dan ZHU Hongyue +1 位作者 ZHAO Yang LIU Yiming 《燃料化学学报(中英文)》 北大核心 2025年第1期128-137,共10页
The nitrogen-coordinated metal single-atom catalysts(M−N−C SACs)with an ultra-high metal loading synthetized by direct high-temperature pyrolysis have been widely reported.However,most of metal single atoms in these c... The nitrogen-coordinated metal single-atom catalysts(M−N−C SACs)with an ultra-high metal loading synthetized by direct high-temperature pyrolysis have been widely reported.However,most of metal single atoms in these catalysts were buried in the carbon matrix,resulting in a low metal utilization and inaccessibility for adsorption of reactants during the catalytic process.Herein,we reported a facile synthesis based on the hard-soft acid-base(HSAB)theory to fabricate Co single-atom catalysts with highly exposed metal atoms ligated to the external pyridinic-N sites of a nitrogen-doped carbon support.Benefiting from the highly accessible Co active sites,the prepared Co−N−C SAC exhibited a superior oxygen reduction reactivity comparable to that of the commercial Pt/C catalyst,showing a high turnover frequency(TOF)of 0.93 e^(−)·s^(-1)·site^(-1)at 0.85 V vs.RHE,far exceeding those of some representative SACs with a ultra-high metal content.This work provides a rational strategy to design and prepare M−N−C single-atom catalysts featured with high site-accessibility and site-density. 展开更多
关键词 hard-soft acid-base Co−N−C single-atom catalyst highly accessible active sites oxygen reduction reaction
在线阅读 下载PDF
A CNT Intercalated Co Porphyrin-Based Metal Organic Framework Catalyst for Oxygen Reduction Reaction
3
作者 Pei-Pei He Jin-Hua Shi +6 位作者 Xiao-Yu Li Ming-Jie Liu Zhou Fang Jing He Zhong-Jian Li Xin-Sheng Peng Qing-Gang He 《电化学(中英文)》 北大核心 2025年第1期31-40,共10页
The poor electronic conductivity of metal-organic framework(MOF)materials hinders their direct application in the field of electrocatalysis in fuel cells.Herein,we proposed a strategy of embedding carbon nanotubes(CNT... The poor electronic conductivity of metal-organic framework(MOF)materials hinders their direct application in the field of electrocatalysis in fuel cells.Herein,we proposed a strategy of embedding carbon nanotubes(CNTs)during the growth process of MOF crystals,synthesizing a metalloporphyrin-based MOF catalyst TCPPCo-MOF-CNT with a unique CNT-intercalated MOF structure.Physical characterization revealed that the CNTs enhance the overall conductivity while retaining the original characteristics of the MOF and metalloporphyrin.Simultaneously,the insertion of CNTs generated adequate mesopores and created a hierarchical porous structure that enhances mass transfer efficiency.X-ray photoelectron spectroscopic analysis confirmed that the C atom in CNT changed the electron cloud density on the catalytic active center Co,optimizing the electronic structure.Consequently,the E_(1/2) of the TCPPCo-MOF-CNT catalyst under neutral conditions reached 0.77 V(vs.RHE),outperforming the catalyst without CNTs.When the TCPPCo-MOF-CNT was employed as the cathode catalyst in assembling microbial fuel cells(MFCs)with Nafion-117 as the proton exchange membrane,the maxi-mum power density of MFCs reached approximately 500 mW·m^(-2). 展开更多
关键词 Metal organic framework CNT intercalated ELECTROCATALYSIS oxygen reduction reaction Microbial fuel cell
在线阅读 下载PDF
Biomass-derived N-doped porous carbon supported single Fe atoms as low-cost and high-performance electrocatalysts for oxygen reduction reaction
4
作者 WANG Li-ping XIAO Jin +1 位作者 MAO Qiu-yun ZHONG Qi-fan 《Journal of Central South University》 2025年第4期1368-1383,共16页
Single-atom catalysts(SACs)are promising for oxygen reduction reaction(ORR)on account of their excellent catalytic activity and maximum utilization of atoms.However,due to the complicated preparation processes and exp... Single-atom catalysts(SACs)are promising for oxygen reduction reaction(ORR)on account of their excellent catalytic activity and maximum utilization of atoms.However,due to the complicated preparation processes and expensive reagents used,the cost of SACs is usually too high to put into practical application.The development of cost-effective and sustainable SACs remains a great challenge.Herein,a low-cost method employing biomass is designed to prepare efficient single-atom Fe-N-C catalysts(SA-Fe-N-C).Benefiting from the confinement effect of porous carbon support and the coordination effect of glucose,SA-Fe-N-C is derived from cheap flour by the two-step pyrolysis.Atomically dispersed Fe atoms exist in the form of Fe-N_(x),which acts as active sites for ORR.The catalyst shows outstanding activity with a half-wave potential(E_(1/2))of 0.86 V,which is better than that of Pt/C(0.84 V).Additionally,the catalyst also exhibits superior stability.The ORR catalyzed by SA-Fe-N-C proceeds via an efficient 4e transfer pathway.The high performance of SA-Fe-N-C also benefits from its porous structure,extremely high specific surface area(1450.1 m^(2)/g),and abundant micropores,which are conducive to increasing the density of active sites and fully exposing them.This work provides a cost-effective strategy to synthesize SACs from cheap biomass,achieving a balance between performance and cost. 展开更多
关键词 oxygen reduction reaction single-atom catalyst porous carbon MICROPORE biomass
在线阅读 下载PDF
A carbon material doped with both porous FeO_(x) and N as an efficient catalyst for oxygen reduction reactions
5
作者 GAO Jian WANG Xin-yao +4 位作者 MENG Ling-xin YIN Zhen MA Na TAN Xiao-yao ZHANG Peng 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第6期1202-1212,共11页
To replace precious metal oxygen reduction reaction(ORR)electrocatalysts,many transition metals and N-doped car-bon composites have been proposed in the last decade resulting in their rapid development as promising no... To replace precious metal oxygen reduction reaction(ORR)electrocatalysts,many transition metals and N-doped car-bon composites have been proposed in the last decade resulting in their rapid development as promising non-precious metal catalysts.We used Ketjenblack carbon as the precursor and mixed it with a polymeric ionic liquid(PIL)of[Hvim]NO_(3) and Fe(NO_(3))_(3),which was thermally calcined at 900℃ to produce a porous FeO_(x),N co-doped carbon material denoted FeO_(x)-N/C.Because the PIL of[Hvim]NO_(3) strongly combines with and disperses Fe^(3+)ions,and NO_(3)−is thermally pyrolyzed to form the porous structure,the FeO_(x)-N/C catalyst has a high electrocatalytic activity for the ORR in both 0.1 mol L^(−1) KOH and 0.5 mol L^(−1) H_(2)SO_(4) electrolytes.It was used as the catalyst to assemble a zinc-air battery,which had a peak power density of 185 mW·cm^(−2).Its superior electrocatalytic activity,wide pH range,and easy preparation make FeO_(x)-N/C a promising electrocatalyst for fuel cells and metal-air batteries. 展开更多
关键词 oxygen reduction reaction Ionic liquid Porous carbon ELECTROCATALYSIS FeOx N co-doping
在线阅读 下载PDF
Magneli phase titanium sub-oxide conductive ceramic Ti_nO_(2n-1) as support for electrocatalyst toward oxygen reduction reaction with high activity and stability 被引量:3
6
作者 伍秋美 阮建明 +1 位作者 周忠诚 桑商斌 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第4期1212-1219,共8页
Magneli phase titanium sub-oxide conductive ceramic Tin O2n-1 was used as the support for Pt due to its excellent resistance to electrochemical oxidation, and Pt/Tin O2n-1 composites were prepared by the impregnation-... Magneli phase titanium sub-oxide conductive ceramic Tin O2n-1 was used as the support for Pt due to its excellent resistance to electrochemical oxidation, and Pt/Tin O2n-1 composites were prepared by the impregnation-reduction method. The electrochemical stability of Tin O2n-1 was investigated and the results show almost no change in the redox region after oxidation for 20 h at 1.2 V(vs NHE) in 0.5 mol/L H2SO4 aqueous solution. The catalytic activity and stability of the Pt/Tin O2n-1 toward the oxygen reduction reaction(ORR) in 0.5 mol/L H2SO4 solution were investigated through the accelerated aging tests(AAT), and the morphology of the catalysts before and after the AAT was observed by transmission electron microscopy. At the potential of 0.55 V(vs SCE), the specific kinetic current density of the ORR on the Pt/Tin O2n-1 is about 1.5 times that of the Pt/C. The LSV curves for the Pt/C shift negatively obviously with the half-wave potential shifting about 0.02 V after 8000 cycles AAT, while no obvious change takes place for the LSV curves for the Pt/Tin O2n-1. The Pt particles supported on the carbon aggregate obviously, while the morphology of the Pt supported on Tin O2n-1 remains almost unchanged, which contributes to the electrochemical surface area loss of Pt/C being about 2times that of the Pt/Tin O2n-1. The superior catalytic stability of Pt/Tin O2n-1 toward the ORR could be attributed to the excellent stability of the Tin O2n-1 and the electronic interaction between the metals and the support. 展开更多
关键词 magneli phase TinO2n-1 support oxygen reduction reaction stability
在线阅读 下载PDF
Red-blood-cell-like nitrogen-doped porous carbon as an efficient metal-free catalyst for oxygen reduction reaction 被引量:2
7
作者 WANG Li-ping TIAN Jing +5 位作者 LI Jing-sha ZENG Xian-guang PENG Zhi-guang HUANG Xiao-bing TANG You-gen WANG Hai-yan 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第6期1458-1468,共11页
A red-blood-cell-like nitrogen-doped porous carbon catalyst with a high nitrogen content(9.81%)and specific surface area(631.46 m^2/g)was prepared by using melamine cyanuric acid and glucose as sacrificial template an... A red-blood-cell-like nitrogen-doped porous carbon catalyst with a high nitrogen content(9.81%)and specific surface area(631.46 m^2/g)was prepared by using melamine cyanuric acid and glucose as sacrificial template and carbon source,respectively.This catalyst has a comparable onset potential and a higher diffusion-limiting current density than the commercial 20 wt%Pt/C catalyst in alkaline electrolyte.The oxygen reduction reaction mechanism catalyzed by this catalyst is mainly through a 4e pathway process.The excellent catalytic activity could origin from the synergistic effect of the in-situ doped nitrogen(up to 9.81%)and three-dimensional(3D)porous network structure with high specific surface area,which is conducive to the exposure of more active sites.It is interesting to note that the catalytic activity of oxygen reduction strongly depends on the proportion of graphic N rather than the total N content. 展开更多
关键词 oxygen reduction reaction nitrogen-doped carbon porous structure red-blood-cell-like morphology
在线阅读 下载PDF
Series Reports from Professor Wei's Group of Chongqing University:Advancements in Electrochemical Energy Conversions(1/4):Report 1:High-performance Oxygen Reduction Catalysts for Fuel Cells 被引量:1
8
作者 Fa-Dong Chen Zhuo-Yang Xie +5 位作者 Meng-Ting Li Si-Guo Chen Wei Ding Li Li Jing Li Zi-Dong Wei 《电化学(中英文)》 CAS 北大核心 2024年第7期1-27,共27页
Two major challenges,high cost and short lifespan,have been hindering the commercialization process of lowtemperature fuel cells.Professor Wei's group has been focusing on decreasing cathode Pt loadings without lo... Two major challenges,high cost and short lifespan,have been hindering the commercialization process of lowtemperature fuel cells.Professor Wei's group has been focusing on decreasing cathode Pt loadings without losses of activity and durability,and their research advances in this area over the past three decades are briefly reviewed herein.Regarding the Pt-based catalysts and the low Pt usage,they have firstly tried to clarify the degradation mechanism of Pt/C catalysts,and then demonstrated that the activity and stability could be improved by three strategies:regulating the nanostructures of the active sites,enhancing the effects of support materials,and optimizing structures of the three-phase boundary.For Pt-free catalysts,especialiy carbon-based ones,several strategies that they proposed to enhance the activity of nitrogen-/heteroatom-doped carbon catalysts are firstly presented.Then,an indepth understanding of the degradation mechanism for carbon-based catalysts is discussed,and followed by the corresponding stability enhancement strategies.Also,the carbon-based electrode at the micrometer-scale,faces the challenges such as low active-site density,thick catalytic layer,and the effect of hydrogen peroxide,which require rational structure design for the integral cathodic electrode.This review finally gives a brief conclusion and outlook about the low cost and long lifespan of cathodic oxygen reduction catalysts. 展开更多
关键词 Fuel cell oxygen reduction reaction Pt-based catalyst Carbon-based catalyst
在线阅读 下载PDF
Porous layered La_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3)perovskite with enhanced catalytic activities for oxygen reduction 被引量:2
9
作者 XU Wei-lai XU Zhi-feng +6 位作者 CHEN Tian-yu ZHONG Xiao-cong XIE Yong-min XIE Xiao-yun CHEN Zhe-qin LIU Jia-ming WANG Rui-xiang 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第5期1305-1315,共11页
Low-cost catalysts with high activity are in immediate demand for energy storage and conversion devices.In this study,polyvinyl pyrrolidone was used as a complexing agent to synthesize La_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)... Low-cost catalysts with high activity are in immediate demand for energy storage and conversion devices.In this study,polyvinyl pyrrolidone was used as a complexing agent to synthesize La_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3)(LSCF)perovskite oxide.The obtained porous layered LSCF has a large specific surface area of 23.74 m^(2)/g,four times higher than that prepared by the traditional sol-gel method(5.08 m^(2)/g).The oxygen reduction reaction activity of the oxide in 0.1 mol/L KOH solution was studied using a rotating ring-disk electrode.In the tests,the initial potential of 0.88 V(vs.reversible hydrogen electrode)and the limiting diffusion current density of 5.02 mA/cm^(2)were obtained at 1600 r/min.Therefore,higher catalytic activity and stability were demonstrated,compared with the preparation of LSCF perovskite oxide by the traditional method. 展开更多
关键词 oxygen reduction reaction ELECTROCATALYST PEROVSKITE layered structure
在线阅读 下载PDF
多壁碳纳米管负载对苯二酸用作氧还原催化剂性能
10
作者 杨晓武 李宏涛 +2 位作者 张康 李培枝 王晨 《分子催化(中英文)》 北大核心 2025年第4期338-345,I0003,共9页
创新性地设计了多壁碳纳米管负载对苯二酸的新型氧还原反应(ORR)催化剂,旨在寻求替代贵金属铂基催化剂的可持续解决方案.该催化剂的制备过程经过精细调控,通过控制多壁碳纳米管(CNTs)与对苯二酸(PTA)的负载比例,优化催化活性中心的分散... 创新性地设计了多壁碳纳米管负载对苯二酸的新型氧还原反应(ORR)催化剂,旨在寻求替代贵金属铂基催化剂的可持续解决方案.该催化剂的制备过程经过精细调控,通过控制多壁碳纳米管(CNTs)与对苯二酸(PTA)的负载比例,优化催化活性中心的分散和电子传递效率.为准确评估该催化剂的综合电化学性能,采用旋转圆盘电极测试系统,评估其在不同电位下的电流密度、过电位等关键指标.实验结果表明,PTA与CNTs的最佳比例为10∶5,该比例下的催化剂展现出卓越的ORR性能;当CNTs比例过高时会掩蔽反应活性位点;而CNTs比例过低时,则可能影响电子传递效率.在最优比例下,催化剂的极限电流密度高达−7.57 mA·cm^(−2),显著优于商业Pt/C催化剂(−4.67 mA·cm^(−2)),表现出优异的催化活性.此外,为考察催化剂的实际应用潜力,还深入评估了其在燃料交叉反应(甲醇)中的稳定性.与商用Pt/C催化剂相比,该催化剂表现出卓越的稳定性,电流波动较小,证明其对燃料交叉反应具有更强的抗干扰能力.这项研究为设计高效、稳定的ORR催化剂提供了一种新方法和新思路. 展开更多
关键词 氧还原 电催化 多壁碳纳米管 对苯二酸
在线阅读 下载PDF
ZIF-8衍生高效Fe-N-C催化剂的制备及其氧还原性能 被引量:1
11
作者 张赛航 姚赢赢 +1 位作者 李钊 邹建新 《材料工程》 北大核心 2025年第3期135-142,共8页
为推动燃料电池的大规模商业化应用,开发高效、稳定和低成本的氧还原(ORR)催化剂具有重要意义。本工作以Fe掺杂ZIF-8为前驱体,通过球磨、高温氩气气氛下煅烧、酸洗后,在氨气气氛下进行二次煅烧,得到Fe-N-C非贵金属催化剂,多种表征手段... 为推动燃料电池的大规模商业化应用,开发高效、稳定和低成本的氧还原(ORR)催化剂具有重要意义。本工作以Fe掺杂ZIF-8为前驱体,通过球磨、高温氩气气氛下煅烧、酸洗后,在氨气气氛下进行二次煅烧,得到Fe-N-C非贵金属催化剂,多种表征手段的结果显示Fe原子均匀分散在氮掺杂的碳骨架上,从而形成丰富的Fe-N_(x)催化活性位点。电化学性能测试结果表明,通过制备工艺和金属比例优化后的Fe-N-C-5%催化剂,在0.1 mol/L HClO_(4)的酸性溶液中表现出优异的ORR活性,半波电位为0.845 V,同时兼具良好的稳定性,在20000次循环后半波电位没有明显下降,这些结果为合理设计非贵金属ORR催化剂提供了有效的策略。 展开更多
关键词 氧还原反应 非贵金属催化剂 质子交换膜燃料电池 电催化 金属有机框架材料
在线阅读 下载PDF
双金属协同电催化及其在典型反应中的应用研究进展
12
作者 杨天璇 武美霞 +5 位作者 陈宁 唐昌强 赵强 王俊丽 郭永 李作鹏 《燃料化学学报(中英文)》 北大核心 2025年第2期211-230,共20页
近年来,双金属非均相协同催化剂的设计和制备,已成为当前材料与催化领域的研究热点。两种组分之间的适当组合,会极大地提升催化剂的催化性能,并且该催化性能提高的程度明显大于单独使用时的催化性能,因而被认为各组分之间存在着相互协... 近年来,双金属非均相协同催化剂的设计和制备,已成为当前材料与催化领域的研究热点。两种组分之间的适当组合,会极大地提升催化剂的催化性能,并且该催化性能提高的程度明显大于单独使用时的催化性能,因而被认为各组分之间存在着相互协同的催化作用。过去的十几年里,双金属协同催化剂在低温燃料电池和电解水制氢领域取得了巨大的进展,本工作总结了近年来双金属协同催化剂在电化学领域中的相关研究,综述了PtRu、NiFe、PtNi三种典型双金属协同催化剂在甲醇氧化、析氧及氧还原方面的协同反应机理及研究进展。从物理化学性质的改变和电子结构的优化多角度分析了第二种金属的加入对催化剂的影响和改变,最后对双金属协同电催化剂的未来发展方向做出了展望。 展开更多
关键词 双金属 协同催化 甲醇氧化 电解水制氢 析氧 氧还原
在线阅读 下载PDF
Pt_(3)Co高指数晶面氧还原过程的密度泛函理论研究
13
作者 刘磊 郭瑞华 +3 位作者 王丽 王艳 张国芳 关丽丽 《无机材料学报》 北大核心 2025年第1期39-46,I0001-I0005,共13页
Pt_(3)Co催化剂是Pt基合金中氧还原反应(ORR)活性最高的催化剂,合成Pt_(3)Co高指数晶面(HIFs)是一种提高其催化性能的有效策略,但具有最高ORR活性的HIFs尚未明确,并且目前缺乏对Pt_(3)Co HIFs ORR的系统研究。本研究构建了六种不同Pt_(3... Pt_(3)Co催化剂是Pt基合金中氧还原反应(ORR)活性最高的催化剂,合成Pt_(3)Co高指数晶面(HIFs)是一种提高其催化性能的有效策略,但具有最高ORR活性的HIFs尚未明确,并且目前缺乏对Pt_(3)Co HIFs ORR的系统研究。本研究构建了六种不同Pt_(3)Co HIFs,通过从头算分子动力学(AIMD)计算证明了其稳定性,通过密度泛函理论(DFT)计算了六种Pt_(3)Co HIFs的ORR过程中间物*O、*OH、*OOH的结合能(BE),通过d带中心(εd)、Bader电荷及配位数(CN)解释了其在台阶与边缘位点BE不同的原因。同时分析了吸附原子CN与εd的关系,通过ORR自由能台阶图分析了ORR过程中的过电位(η),发现η大小主要与*OH结合能(BE-*OH)有关,其中η最小的晶面为Pt_(3)Co(211),其在台阶处的η达到了0.294 eV。本工作为高ORR活性HIFs催化剂研发提供了一定的理论依据。 展开更多
关键词 Pt_(3)Co催化剂 高指数晶面 密度泛函理论 氧还原反应
在线阅读 下载PDF
Fe/N/C三维气凝胶自支撑催化剂的氧还原性能
14
作者 姚熙晨 王书贤 +2 位作者 汪云 王诚 张创 《无机化学学报》 北大核心 2025年第7期1387-1396,共10页
以过硫酸铵引发吡咯单体原位聚合形成的三维多孔气凝胶为载体,以二茂铁为金属前驱体,在氩气气氛下通过高温热解法制备出系列不同铁负载量的Fe/N/C催化剂。结果表明,基于气凝胶载体制备的催化剂在酸性介质中展现出优异的氧还原反应(ORR)... 以过硫酸铵引发吡咯单体原位聚合形成的三维多孔气凝胶为载体,以二茂铁为金属前驱体,在氩气气氛下通过高温热解法制备出系列不同铁负载量的Fe/N/C催化剂。结果表明,基于气凝胶载体制备的催化剂在酸性介质中展现出优异的氧还原反应(ORR)活性及稳定性。当二茂铁载量为12 mg时制得的催化剂性能最佳,其半波电位达0.691 V(vs RHE),平均电子转移数为3.97,表明反应过程接近理想的四电子路径。另外,该催化剂经10000圈循环伏安测试后,半波电位仅衰减11 mV,展现出较好的电化学耐久性。 展开更多
关键词 非贵金属催化剂 Fe/N/C催化剂 气凝胶 氧还原反应 燃料电池
在线阅读 下载PDF
溶氧型海水电池碳纤维正极的苯胺氮掺杂改性及其氧还原催化性能
15
作者 班晓倩 王凯 +1 位作者 芦永红 徐海波 《燃料化学学报(中英文)》 北大核心 2025年第8期1183-1190,共8页
碳纤维用做溶氧型海水电池(DO-SWB,Dissolved Oxygen-Seawater Battery)正极材料已取得商业化应用,但海水中溶解氧浓度低和材料氧还原反应(ORR,oxygen reduction reaction)活性低制约着电池功率密度的提高,炭材料的氮掺杂近年来备受关... 碳纤维用做溶氧型海水电池(DO-SWB,Dissolved Oxygen-Seawater Battery)正极材料已取得商业化应用,但海水中溶解氧浓度低和材料氧还原反应(ORR,oxygen reduction reaction)活性低制约着电池功率密度的提高,炭材料的氮掺杂近年来备受关注。本工作以苯胺为氮源,采用一步法在苯胺(An,Aniline)和硫酸混合液中对聚丙烯腈碳纤维(PAN-CF,Polyacrylonitrile-based Carbon Fiber)进行电化学处理,调控工艺条件制备掺氮电极。采用扫描电镜(SEM,Scanning Electron Microscope)、拉曼光谱(Raman,Raman spectrum)和X射线光电子能谱(XPS,Xray Photoelectron Spectroscope)进行表征,结合电化学测试方法对电极表面特征及ORR活性评价,并对作用机理分析。电化学改性使碳纤维表面产生缺陷并生成吡啶类官能团,有效调控了炭材料的电子结构,增加了电极表面活性位点的数量,改善了氧的吸附和电荷转移能力,使掺氮后电极具有优良的ORR性能。其中,最佳性能电极ORR起始电位为-0.12 V vs SCE,在-0.4 V vs SCE下比电流密度达510 mA/g,作为溶氧型海水电池正极具有可期的应用前景。 展开更多
关键词 溶氧型海水电池 电化学改性 碳纤维正极 氮掺杂 氧还原反应
在线阅读 下载PDF
锐钛矿TiO_(2- x )(101)表面硝酸根还原路径的第一性原理计算
16
作者 贺曦煜 杨帆 章俊良 《上海交通大学学报》 北大核心 2025年第7期1050-1058,I0005,I0006,共11页
为研究硝酸根在锐钛矿TiO_(2-x)(101)表面的还原过程,建立有无氧空位两种表面模型,采用密度泛函理论对硝酸根在两种表面的还原过程进行理论计算,研究氧空位对表面电子结构、硝酸根吸附构型以其吸附能、还原路径、竞争反应和产物选择性... 为研究硝酸根在锐钛矿TiO_(2-x)(101)表面的还原过程,建立有无氧空位两种表面模型,采用密度泛函理论对硝酸根在两种表面的还原过程进行理论计算,研究氧空位对表面电子结构、硝酸根吸附构型以其吸附能、还原路径、竞争反应和产物选择性的影响.结果表明:氧空位改变硝酸根在表面的吸附构型,显著降低其吸附能,并将电位决定步由硝酸根吸附转变为N原子的氢化过程.此外,氧空位能够大幅提高中间体NO_(2)和NO的脱附能,从而抑制副产物的产生,改善催化剂选择性.氧空位对竞争性析氢反应的促进作用远不及对硝酸根还原反应的促进程度,因此含氧空位的TiO_(2)是电催化硝酸根还原产氨的潜在优异催化剂. 展开更多
关键词 TiO_(2) 氧空位 硝酸根还原 电催化 第一性原理计算
在线阅读 下载PDF
硫掺杂石墨烯阴极在微生物燃料电池中的性能研究
17
作者 刘丽华 许文锋 +4 位作者 贺琦 蓝瑞嵩 张倩 陈博彦 洪俊明 《工业水处理》 北大核心 2025年第4期133-138,共6页
通过水热法将硫原子掺杂到石墨烯结构中,利用单室反应器装置搭建微生物燃料电池(MFC)。采用硫掺杂石墨烯(S-rGO)、活性炭(AC)和炭黑(CB)作为阴极催化剂,选用不同的比例进行混合。发现m(AC)∶m(CB)∶m(S-rGO)为1∶0.25∶0.075时,MFC反应... 通过水热法将硫原子掺杂到石墨烯结构中,利用单室反应器装置搭建微生物燃料电池(MFC)。采用硫掺杂石墨烯(S-rGO)、活性炭(AC)和炭黑(CB)作为阴极催化剂,选用不同的比例进行混合。发现m(AC)∶m(CB)∶m(S-rGO)为1∶0.25∶0.075时,MFC反应器表现出最佳性能,最大输出电压为295 mV,功率密度为256 mW/cm^(2)。此外,S-rGO的极限电流密度为3.46 mA/cm^(2),高于rGO(3.22 mA/cm^(2)),表明S-rGO具有优异的电化学性能和稳定性。应对有机物冲击方面,S-rGO修饰的MFC能够提高污水的COD和TN的去除,相较于rGO,分别提升了2.5%和5.0%。因此,S-rGO是一种高效、稳定的MFC阴极催化剂,不仅能够提高MFC的电能转化效率,还能够提高MFC的污水处理能力,具有广阔的应用前景。 展开更多
关键词 硫掺杂石墨烯 氧还原反应 微生物燃料电池
在线阅读 下载PDF
基于流态化活化的煤基燃料O_(2)/CO_(2)燃烧碳捕集技术研究进展
18
作者 张海霞 沈威 +5 位作者 朱治平 刘晓星 徐贵玲 齐晓宾 曹晓阳 颜雲飞 《洁净煤技术》 北大核心 2025年第4期62-77,共16页
我国承诺将在2030年前推动CO_(2)排放量达到峰值,进而在2060年前达成碳中和目标。目前,煤炭等化石能源在我国能源消费结构中仍占据相当比重,对保障能源供应的稳定性与安全性意义重大。采用碳捕集技术,可以有效降低碳排放,甚至实现近零排... 我国承诺将在2030年前推动CO_(2)排放量达到峰值,进而在2060年前达成碳中和目标。目前,煤炭等化石能源在我国能源消费结构中仍占据相当比重,对保障能源供应的稳定性与安全性意义重大。采用碳捕集技术,可以有效降低碳排放,甚至实现近零排放,助力能源转型稳步推进。富氧燃烧是燃烧中碳捕集的核心工艺,具有CO_(2)浓度高、捕集成本低、燃烧效率高、污染物排放少等优势,因而具有广阔的应用前景。为拓宽富氧燃烧技术的燃料适应性并增强其与工业领域的适配性,提出了碳基原料流态化活化技术新思路,采用该技术可制备气固活化态类气体燃料,进而通过类气体燃料的富氧燃烧,实现碳捕集;或通过类气体燃料的富氧气化,制取富CO合成气,用于化学品合成,实现CO_(2)资源化利用。首先剖析了流态化活化技术的基本原理,阐明了CO_(2)在该过程中的作用机制。然后,全面综述了碳基原料经流态化活化后所得煤气的特性和活化半焦的特性,重点探究了活化温度、碳与CO_(2)物质的量比(CC比)、反应气氛、氧气浓度及燃料种类等对煤气组成、煤气产率、煤气热值的影响,同时还研究了这些因素对活化半焦粒径分布、微观形貌、比表面积、孔隙结构、碳架结构、反应活性等的影响规律。此外,梳理了气固活化态类气体燃料在O_(2)/CO_(2)气氛下的气化特性,考察了燃料特性、CO_(2)浓度和O_(2)/C物质的量比等对气化性能指标的影响;梳理了气固活化态类气体燃料在O_(2)/CO_(2)气氛下的燃烧特性,总结归纳了NO_(x)排放规律及反应调控机理。最后,对流态化活化技术进行了总结和展望,以期为工业领域燃烧中碳捕集技术及CO_(2)的大规模资源化利用提供理论依据和数据支撑。 展开更多
关键词 流态化活化 类气体燃料 富氧燃烧 碳捕集 CO_(2)还原 CO_(2)资源化利用
在线阅读 下载PDF
B,N共掺杂富勒烯C_(70)作为氧还原和氧析出非金属电催化剂的理论研究
19
作者 杨思伟 黄旭日 《高等学校化学学报》 北大核心 2025年第4期70-79,共10页
采用密度泛函理论研究了B,N共掺杂富勒烯C_(70)[C_(68)B(n)N(m),n,m=1~5,分别代表B和N取代的C位点]的氧还原反应(ORR)和氧析出反应(OER)性能.结果表明,C_(68)B(n)N(m)在热力学上是稳定的,且其ΔG_(*O)OH和ΔG_(*O)与ΔG_(*OH)均呈良好... 采用密度泛函理论研究了B,N共掺杂富勒烯C_(70)[C_(68)B(n)N(m),n,m=1~5,分别代表B和N取代的C位点]的氧还原反应(ORR)和氧析出反应(OER)性能.结果表明,C_(68)B(n)N(m)在热力学上是稳定的,且其ΔG_(*O)OH和ΔG_(*O)与ΔG_(*OH)均呈良好的线性关系.其中,C_(68)B(4)N(2)与C_(68)B(5)N(2)催化剂的ORR过电位为0.45 V,与商业Pt催化剂相当;C_(68)B(4)N(1)的OER过电位最低(0.38 V),优于传统RuO_(2)催化剂(0.42 V),C_(68)B(1)N(3)也表现出与RuO_(2)相当的OER活性.通过精确调控B,N共掺杂位置,可显著降低ORR与OER过电位,提升C_(70)的催化性能.根据活性趋势图,C_(68)B(n)N(m)的最佳ORR和OER活性分别出现在ΔG_(*O)-ΔG_(*OH)=0.92 eV和ΔG_(*O)-ΔG_(*OH)=1.42 eV处.研究结果为设计和发现新的非金属碳基电催化剂提供了线索. 展开更多
关键词 非金属电催化剂 氧还原反应 氧析出反应 密度泛函理论
在线阅读 下载PDF
快速微波合成铂铜合金作为高效氧还原电催化剂 被引量:1
20
作者 袁程 沈迁 +1 位作者 张瑞文 张世明 《储能科学与技术》 北大核心 2025年第3期1133-1140,共8页
氧还原反应(ORR)动力学迟缓,质子交换膜燃料电池(PEMFC)阴极需要消耗大量的贵金属铂(Pt)。然而,Pt的稀缺性以及商业Pt/C催化剂的高成本、低ORR活性、差稳定性等问题,严重制约了PEMFC的大规模应用。因此,亟需寻找合适策略以开发具有优异... 氧还原反应(ORR)动力学迟缓,质子交换膜燃料电池(PEMFC)阴极需要消耗大量的贵金属铂(Pt)。然而,Pt的稀缺性以及商业Pt/C催化剂的高成本、低ORR活性、差稳定性等问题,严重制约了PEMFC的大规模应用。因此,亟需寻找合适策略以开发具有优异活性、高稳定性、低Pt用量的高效实用催化剂。本工作发展了一种快速微波还原的方法,合成了碳负载的铂铜合金纳米颗粒(PtCu/C)催化剂。透射电镜结果显示,PtCu纳米颗粒均匀分布在碳载体表面,其平均粒径约为2.7 nm,纳米颗粒中Pt、Cu均匀分布,形成了两个原子层厚度的富Pt表面结构;X射线衍射证实了PtCu合金的形成;X射线光电子能谱表明Cu向Pt进行了电子转移,产生了电子相互作用。进一步,系统考察了前体混合物中Pt∶Cu摩尔比以及微波反应的温度、时间、功率等对制备催化剂催化活性的影响。电化学测试结果表明,优化的PtCu/C催化剂在0.9 V(vs.RHE)处的质量活性和面积活性分别为0.280A/mg和0.346 mA/cm^(2),均优于商业Pt/C催化剂的0.150A/mg和0.213 mA/cm^(2),且稳定性进一步提升,PtCu/C催化剂提高的活性和稳定性主要归因于小粒径的PtCu纳米颗粒、合金化以及富Pt表面结构等。 展开更多
关键词 快速微波还原 铂铜合金 电催化剂 氧还原反应
在线阅读 下载PDF
上一页 1 2 33 下一页 到第
使用帮助 返回顶部