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Selective electrocatalytic CO2 reduction enabled by SnO2 nanoclusters 预览
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作者 Hui Yang Yang Huang +5 位作者 Jun Deng Yunling Wu Na Han Chenyang Zha Leigang Li Yanguang Li 《能源化学:英文版》 SCIE EI CAS CSCD 2019年第10期93-96,共4页
The development of high-performance electrocatalysts holds the decisive key to the electrochemical CO2 reduction toward value-added products. Formic acid or formate is a desirable reduction product, but its selective ... The development of high-performance electrocatalysts holds the decisive key to the electrochemical CO2 reduction toward value-added products. Formic acid or formate is a desirable reduction product, but its selective production is often challenging. Tin based-materials have attracted great attention for formate production, and yet their performances are far from satisfactory. In this study, we reported the preparation of SnO2 nanoclusters from the controlled self-polymerization of dopamine together with SnO32-, followed by the mild-temperature calcination. The final product consisted of large primary particles that were further made of small secondary SnO2 nanocrystals. When evaluated as the electrocatalyst for CO2 reduction in 0.5 M NaHCO3, our material exhibited impressive activity, selectivity and stability for the selective CO2 reduction to formate. A peak formate Faradaic efficiency of~73% and large partial current density of 16.3 mA/cm2 was achieved at -0.92 V versus reversible hydrogen electrode. 展开更多
关键词 CO2 REDUCTION reaction ELECTROCATALYSTS FORMATE Tin oxide Selectivity
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High-Index-Faceted Ni3S2 Branch Arrays as Bifunctional Electrocatalysts for Efficient Water Splitting
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作者 Shengjue Deng Kaili Zhang +8 位作者 Dong Xie Yan Zhang Yongqi Zhang Yadong Wang Jianbo Wu Xiuli Wang Hong Jin Fan Xinhui Xia Jiangping Tu 《纳微快报:英文版》 CAS CSCD 2019年第1期205-216,共12页
For efficient electrolysis of water for hydrogen generation or other valueadded chemicals,it is highly relevant to develop low-temperature synthesis of low-cost and high-e ciency metal sulfide electrocatalysts on a la... For efficient electrolysis of water for hydrogen generation or other valueadded chemicals,it is highly relevant to develop low-temperature synthesis of low-cost and high-e ciency metal sulfide electrocatalysts on a large scale.Herein,we construct a new core–branch array and binder-free electrode by growing Ni3S2 nanoflake branches on an atomic-layer-deposited(ALD)TiO2 skeleton.Through induced growth on the ALD-TiO2 backbone,cross-linked Ni3S2 nanoflake branches with exposed{210}highindex facets are uniformly anchored to the preformed TiO2 core forming an integrated electrocatalyst.Such a core–branch array structure possesses large active surface area,uniform porous structure,and rich active sites of the exposed{210}high-index facet in the Ni3S2 nanoflake.Accordingly,the TiO2@Ni3S2 core/branch arrays exhibit remarkable electrocatalytic activities in an alkaline medium,with lower overpotentials for both oxygen evolution reaction(220 mV at 10 mA cm-2)and hydrogen evolution reaction(112 m V at 10 mA cm-2),which are better than those of other Ni3S2 counterparts.Stable overall water splitting based on this bifunctional electrolyzer is also demonstrated. 展开更多
关键词 Nickel sulfide Core/branch ARRAYS Porous film BIFUNCTIONAL ELECTROCATALYSTS Electrochemical water splitting Oxygen EVOLUTION reaction(OER) Hydrogen EVOLUTION reaction(HER)
钴/铁双金属有机框架材料用于电催化析氧反应 预览
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作者 谢士礼 李斐 +2 位作者 许素显 李佳原 曾伟 《催化学报》 SCIE EI CAS CSCD 北大核心 2019年第8期1205-1211,共7页
开发高效且稳定的电催化剂用于水氧化反应对于能源存储与转化系统至关重要.目前商业贵金属材料(如IrO2和RuO2)拥有最好的电催化析氧性能,但其稀缺性和高成本阻碍了它们的实际应用.金属有机框架材料(MOFs)由于具有比表面积大、周期性结... 开发高效且稳定的电催化剂用于水氧化反应对于能源存储与转化系统至关重要.目前商业贵金属材料(如IrO2和RuO2)拥有最好的电催化析氧性能,但其稀缺性和高成本阻碍了它们的实际应用.金属有机框架材料(MOFs)由于具有比表面积大、周期性结构、孔径可调、金属中心和有机配体多样性等特点,已经广泛应用于药物输送、气体存储、催化、传感等领域.在电催化领域, MOFs通常作为前驱体或模板在高温下热解来制备金属氧化物/多孔碳复合材料,虽然它们显示出较高的催化活性,但是往往需要复杂的制备工艺和高温条件.因此,利用MOFs的固有活性不经过热解处理直接使用MOFs作为析氧反应(OER)电催化剂是非常有意义的.由于氧化态的钴中心有利于OOH物种的形成并可促进OOH脱质子形成氧气,钴基材料已经显示出很好的OER性能.尤其是当Fe掺杂进钴基催化剂时, OER性能可得到进一步提高.因此,开发一种高效的Co/Fe双金属MOFs用于电催化析氧反应是很好的选择.本文以Co^2+和Fe^3+为金属离子,以均苯三甲酸为有机配体,在三乙胺存在条件下通过简单的超声法合成了一系列不同Co/Fe比的双金属MOFs.以电催化性能最好的Co2Fe-MOF为研究对象,从扫描电子显微镜和透射电子显微镜图可以看出Co2Fe-MOF由松散堆积的纳米粒子组成,这种结构具有较大的比表面积,从而可以暴露更多的催化活性位点.电化学测试结果表明,在所有的CoxFe-MOFs中, Co2Fe-MOF达到10 mA cm^-2的电流密度需要的过电位(280 mV)最低,且低于大部分文献报道的钴/铁双金属催化剂.而且Co2Fe-MOF的Tafel斜率低至44.7 mV dec^-1,表明在电催化过程中有较快的反应动力学.电化学阻抗分析表明, Co2Fe-MOF有较小的电荷转移电阻,有利于电子从电解液到电极表面的传递. XPS测试分析表明, Fe的加入可以调节Co金属中心周围的电子环境,有利于提升催化剂的 展开更多
关键词 双金属有机框架材料 析氧反应 电催化剂 协同效应 超声法
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In situ redox growth of mesoporous Pd-Cu2O nanoheterostructures for improved glucose oxidation electrocatalysis
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作者 Ying Guo Jianwen Liu +5 位作者 Yi-Tao Xu Bo Zhao Xuewan Wang Xian-Zhu Fu Rong Sun Ching-Ping Wong 《科学通报:英文版》 SCIE EI CSCD 2019年第11期764-773,共10页
Interfaces of metal-oxide heterostructured electrocatalyst are critical to their catalytic activities due to the significant interfacial effects. However, there are still obscurities in the essence of interfacial effe... Interfaces of metal-oxide heterostructured electrocatalyst are critical to their catalytic activities due to the significant interfacial effects. However, there are still obscurities in the essence of interfacial effects caused by crystalline defects and mismatch of electronic structure at metal-oxide nanojunctions. To deeply understand the interfacial effects, we engineered crystalline-defect Pd-Cu2O interfaces through nonepitaxial growth by a facile redox route. The Pd-Cu2O nanoheterostructures exhibit much higher electrocatalytic activity toward glucose oxidation than their single counterparts and their physical mixture,which makes it have a promising potential for practical application of glucose biosensors.Experimental study and density functional theory(DFT) calculations demonstrated that the interfacial electron accumulation and the shifting up of d bands center of Cu-Pd toward the Fermi level were responsible for excellent electrocatalytic activity. Further study found that Pd(3 1 0) facets exert a strong metaloxide interface interaction with Cu2O(1 1 1) facets due to their lattice mismatch. This leads to the sinking of O atoms and protruding of Cu atoms of Cu2O, and the Pd crystalline defects, further resulting in electron accumulation at the interface and the shifting up of d bands center of Cu-Pd, which is different from previously reported charge transfer between the interfaces. Our findings could contribute to design and development of advanced metal-oxide heterostructured electrocatalysts. 展开更多
关键词 METAL-OXIDE interfaces CRYSTALLINE defects INTERFACIAL electron accumulation ELECTROCATALYSTS Density functional theory
Low-temperature plasma technology for electrocatalysis
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作者 Dongdong Wang Yuqin Zou +5 位作者 Li Tao Yiqiong Zhang Zhijuan Liu Shiqian Du Shuangquan Zang Shuangyin Wang 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第4期826-838,共13页
Electrochemical reactions were widely used in energy storage and conversion devices. The development of low-cost, highly efficient and stable electrocatalyst is essential to a large-scale application of energy storage... Electrochemical reactions were widely used in energy storage and conversion devices. The development of low-cost, highly efficient and stable electrocatalyst is essential to a large-scale application of energy storage and conversion devices. Recently, emerging plasma technology has been employed as one of the practical ways to synthesize and modify electrocatalysts due to its unique property. In this review, we summarized the latest applications of plasma in energy storage and conversion, including using it as the preparation and modification technology of the various electrocatalysts and the usage of it as the synthesis technology directly. Firstly, we presented the definition and types of plasma reactors and their respective characteristics. Then, these applications of plasma technology in many essential electrode reactions including carbon dioxide reduction reaction (CO2RR), nitrogen fixation, oxygen reduction reaction (ORR), oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) were introduced. Finally, the challenges and outlook of plasma technology in energy storage and conversion were summarized, and the solutions and prospected its development in the future were present. Through reviewing the related aspects, readers can have a deeper understanding of the application prospects of plasma in electrocatalysis. 展开更多
关键词 Plasma ELECTROCATALYSTS ELECTRODE REACTIONS ENERGY storage ENERGY conversion
Rational synthesis of CaCo2O4 nanoplate as an earth-abundant electrocatalyst for oxygen evolution reaction 预览
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作者 Xiao Lin Jing Zhou +6 位作者 Dehua Zheng Chengzhi Guan Guoping Xiao Ning Chen Qing Liu Hongliang Bao Jian-Qiang Wang 《能源化学:英文版》 SCIE EI CAS CSCD 2019年第4期125-131,共7页
To accelerate the kinetics of oxygen evolution reaction (OER) regarding the energy conversion and storage approaches,the discovery of desirable cost-effective and highly efficient electrocatalysts is of prime importan... To accelerate the kinetics of oxygen evolution reaction (OER) regarding the energy conversion and storage approaches,the discovery of desirable cost-effective and highly efficient electrocatalysts is of prime importance.This study dem on strates a layered CaCo2O4 with a two-dimensional nan opiate structure,which possesses electrocatalytic activity for OER.The OER activity was achieved on CaCo2O4 with a Tafel slope of 71 mV dec^-1 and a current density of 10 mA cm^-2 at an overpotential of 371 mV,which was more active than the similar structure LiCoO2 catalyst.Combined with X-ray absorption fine structure and density functional theory calculations,the enhanced OER activity and stability are mainly attributed to the unique electronic structure derived from the interaction of Ca and Co,and improved electrical conductivity.CaCo2O4 can be developed as a highly active and earth-abundant catalyst for OER in energy conversion and storage technologies. 展开更多
关键词 OXYGEN evolution reaction CaCo2O4 2D NANOPLATES ELECTROCATALYSTS
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Co-Mn掺杂碳气凝胶的制备与性能
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作者 臧君娇 倪晓慧 +4 位作者 王栋 曹美莲 迟祥 程万里 韩广萍 《复合材料学报》 EI CAS CSCD 北大核心 2019年第9期2196-2203,共8页
为探究不同碳化温度对Co-Mn掺杂碳气凝胶(Co-Mn/CA)电催化析氢性能的影响,以资源丰富且可再生的木质纤维素为碳源、四水乙酸钴为钴源、四水乙酸锰为Mn源,通过水热法制备出Co-Mn/CA。研究发现,纤维素气凝胶碳化后表面形貌发生改变,由片... 为探究不同碳化温度对Co-Mn掺杂碳气凝胶(Co-Mn/CA)电催化析氢性能的影响,以资源丰富且可再生的木质纤维素为碳源、四水乙酸钴为钴源、四水乙酸锰为Mn源,通过水热法制备出Co-Mn/CA。研究发现,纤维素气凝胶碳化后表面形貌发生改变,由片层结构转变为多孔结构,使其活性位点数量增多,电催化析氢活性增加。通过XRD和N2吸-脱附对其结构进行了表征处理分析,结果表明,经碳化处理后的CA产物以无定型碳为主,经900℃碳化处理后的CA(CA-900)比表面积和总孔隙体积均为最大,分别为958 m2·g-1和0.33cm3·g-1。电化学性能测试表明,Co-Mn/CA-900表现出最好的电催化析氢反应(HER)催化活性,在1mol/L KOH电解液中、50mA·cm-2的电流密度下,具有175mV的过电势,经过10h的计时电位测试,压降仅为7%,表现出较好的电催化析氢稳定性。 展开更多
关键词 木质纤维素 碳气凝胶 Co-Mn掺杂 析氢反应 电催化剂
钙钛矿型氧化物的制备及其在氧/空气双功能电极中的应用 预览
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作者 庄树新 何佳怡 +4 位作者 张伟鹏 周南 路密 廉冀琼 孙婧婧 《中南大学学报:英文版》 SCIE EI CAS CSCD 2019年第6期1387-1401,共15页
本文综述了近期钙钛矿型氧化物在氧/空气电极中作为氧还原和氧析出双功能电催化剂的制备方法。详细地介绍了各种制备方法并对其优缺点进行比较分析,发现不同的制备方法对钙钛矿型氧化物的形貌和物理化学性能的影响很大。钙钛矿型氧化物... 本文综述了近期钙钛矿型氧化物在氧/空气电极中作为氧还原和氧析出双功能电催化剂的制备方法。详细地介绍了各种制备方法并对其优缺点进行比较分析,发现不同的制备方法对钙钛矿型氧化物的形貌和物理化学性能的影响很大。钙钛矿型氧化物作为双能电催化剂被广泛应用于金属-空气电池中,归纳了其制备方法与电催化性能之间的关系。在氧/空气电极应用中,重点讨论了影响钙钛矿型氧化物的结构稳定性、相组成和电催化活性的因素,指出了其作为双功能电催化剂在实际应用中存在的主要问题,并对今后的研究方向进行预测。 展开更多
关键词 钙钛矿型氧化物 电催化剂 制备方法 氧/空气电极
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碳基材料在电催化析氢反应中的应用 预览
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作者 张泽霞 吕瑞涛 +1 位作者 黄正宏 康飞宇 《新型炭材料》 SCIE EI CAS CSCD 北大核心 2019年第2期115-131,共17页
氢作为一种高燃烧热值的清洁能源载体,对于解决当前日益严峻的能源短缺和环境污染问题具有重要意义。与传统的化石燃料(如天然气、煤)重整制氢相比,电催化分解水作为一种清洁可再生的制氢工艺具有重要的应用前景。但目前常用的电解水析... 氢作为一种高燃烧热值的清洁能源载体,对于解决当前日益严峻的能源短缺和环境污染问题具有重要意义。与传统的化石燃料(如天然气、煤)重整制氢相比,电催化分解水作为一种清洁可再生的制氢工艺具有重要的应用前景。但目前常用的电解水析氢反应(HER)催化剂多为贵金属基(如Pt)材料,储量稀少且成本高昂,因此开发低成本、高活性的非贵金属HER催化剂是当前该领域研究面临的重要挑战。本文综述了近年来碳基材料用于HER催化研究的相关进展。根据碳基材料在HER催化剂中扮演的功能将其分为两大类:活性相和复合相。作为活性相时,通过异质原子掺杂等方式激活其本征活性,直接应用于催化析氢反应;作为复合相时,其作用有导电基底、高分散载体、耐腐蚀防护层等,通过协同增强效应,提高复合催化剂的整体活性,目前个别非贵金属催化剂的活性几乎可以与Pt基催化剂相媲美。本文总结了这些新型碳基HER催化剂的研究进展及其性能调控策略,并对未来开发低成本、高效率的HER催化剂的探索方向进行了展望。 展开更多
关键词 碳基材料 析氢反应 电催化剂 电解水制氢 纳米结构 催化活性
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Decorating cobalt phosphide and rhodium on reduced graphene oxide for high-efficiency hydrogen evolution reaction 预览
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作者 Haiyan Zheng Xiubing Huang +4 位作者 Hongyi Gao Wenjun Dong Guilong Lu Xiao Chen Ge Wang 《能源化学:英文版》 SCIE EI CAS CSCD 2019年第7期72-79,共8页
Electrochemical reduction of water to hydrogen holds great promise for clean energy,while its widespread application relies on the development of efficient catalysts with large surface area,abundant exposed active sit... Electrochemical reduction of water to hydrogen holds great promise for clean energy,while its widespread application relies on the development of efficient catalysts with large surface area,abundant exposed active sites and superior electron conductivity.Herein,we report a facile strategy to configure an electrocatalyst composed of cobalt phosphide and rhodium uniformly anchored on reduced graphene oxide for hydrogen generation.The hybrids effectively integrate the exposed active sites,electron conductivity and synergistic effect of the catalyst.Electrochemical tests exhibit that the catalyst shows superior hydrogen evolution reaction catalytic activity and stability,with a small Tafel slope of 43 m V dec-1.Overpotentials as low as 29 and 72 mV are required to achieve current densities of 2 and 10 mA cm-2in 0.5M H2SO4,respectively.The hybrid constitution with highly active sites on conductive substrate is a new strategy to synthesize extremely efficient electrocatalysts.Especially,the efficient synergistic effect among cobalt phosphide,rhodium and reduced graphene oxide provides a novel approach for configuring electrocatalysts with high electron efficiency. 展开更多
关键词 REDUCED graphene oxide COBALT PHOSPHIDE Hydrogen evolution reaction ELECTROCATALYSTS SYNERGISTIC effect
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Transforming Co3O4 nanosheets into porous N-doped CoxOy nanosheets with oxygen vacancies for the oxygen evolution reaction 预览
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作者 Lei Xu Yuqin Zou +1 位作者 Zhaohui Xiao Shuangyin Wang 《能源化学:英文版》 SCIE EI CAS CSCD 2019年第8期24-29,I0002共7页
Cobalt oxides have been widely investigated as promising replacements for noble metal-based catalysts for oxygen evolution reaction(OER). Herein, we, for the first time, have obtained porous CoxOy nanosheets with N-do... Cobalt oxides have been widely investigated as promising replacements for noble metal-based catalysts for oxygen evolution reaction(OER). Herein, we, for the first time, have obtained porous CoxOy nanosheets with N-doping and oxygen vacancies by etching Co3O4 nanosheets with NH3 plasma. Comparing with the pristine Co3O4 nanosheets(1.79 V), the porous CoxOy nanosheets with N-doping and oxygen vacancies have a much lower potential of 1.51 V versus RHE to reach the current density of 10 mA cm-2. The obtained sample has a lower Tafel slope of 68 m V dec-1 than the pristine Co3O4 nanosheets(234 mV dec-1).The disclosed Co^2+, which is responsible for the formation of active sites(CoOOH), N-doping and oxygen vacancies, gives rise to better performance of OER. 展开更多
关键词 ELECTROCATALYSTS OXYGEN evolution reaction Cobalt oxides N doping OXYGEN VACANCIES
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预嵌锂硬碳和软碳用于锂离子电容器负极的比较研究
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作者 李钊 孙现众 +3 位作者 刘文杰 张熊 王凯 马衍伟 《电化学》 CAS CSCD 北大核心 2019年第1期122-136,共15页
锂离子电容器是一种应用前景广阔的电化学储能器件.目前,活性炭作为锂离子电容器正极被广泛使用.然而,锂离子电容器负极却有多种不同选择,如硬碳和软碳等碳材料.本文使用两种具有不同结构和电化学特性的硬碳和软碳材料作为锂离子电容器... 锂离子电容器是一种应用前景广阔的电化学储能器件.目前,活性炭作为锂离子电容器正极被广泛使用.然而,锂离子电容器负极却有多种不同选择,如硬碳和软碳等碳材料.本文使用两种具有不同结构和电化学特性的硬碳和软碳材料作为锂离子电容器负极,进行了对比研究.研究表明,软碳相比于硬碳有更好的电子导电性和更高的可逆容量.通过在电流范围0.1~12 A·g^-1下进行充放电测试,分别研究了两种碳基电极在不同涂覆厚度下的倍率性能.结果显示,硬碳电极在大电流下有更好的倍率特性.然后,以活性炭为正极,预嵌锂的硬碳和软碳为负极,锂片为锂源和参比电极,分别组装了三电极软包锂离子电容器.根据三电极充放电测试,分别研究了不同预嵌锂量的硬碳和软碳所组装的锂离子电容器的电化学性能.结果表明,合适的负极预嵌锂容量可以提升锂电容的能量密度、功率密度和循环稳定性.最后,大容量硬碳和软碳基软包锂离子电容器被分别组装,软碳基锂电容实现了最高的能量密度21.2 Wh·kg^-1(基于整个器件质量),硬碳基锂电容实现最高的功率密度5.1 kW·kg^-1. 展开更多
关键词 锂离子电容器 硬碳 软碳 预嵌锂 软包电容器
Two-in-one solution using insect wings to produce graphene-graphite films for efficient electrocatalysis
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作者 Huaiyu Li Lihan Zhang +7 位作者 Long Li Chaowen Wu Yajiao Huo Ying Chen Xijun Liu Xiaoxing Ke Jun Luo Gustaaf Van Tendeloo 《纳米研究:英文版》 SCIE EI CAS CSCD 2019年第1期33-39,共7页
Natural organisms contain rich elements and naturally optimized smart structures,both of which have inspired various innovative concepts and desig ns in human society.In particular,several natural organisms have been ... Natural organisms contain rich elements and naturally optimized smart structures,both of which have inspired various innovative concepts and desig ns in human society.In particular,several natural organisms have been used as element sources to synthesize low-cost and environmentally friendly electrocatalysts for the oxygen reduction reaction(ORR)in fuel cells and metal-air batteries,which are clean energy devices.However,to date,no naturally optimized smart structures have been employed in the synthesis of ORR catalysts,including graphene-based materials.Here,we demonstrate a novel strategy to synthesize graphene-graphite films(GGFs)by heating butterfly wings coated with FeCI3 in N2,in which the full power of natural organisms is utilized.The wings work not only as an element source for GGF generation but also as a porous supporting structure for effective nitrogen doping,two-dimensional spreading,and double-face exposure of the GGFs.These GGFs exhibit a half-wave potential of 0.942 V and a H2O2 yield of<0.07%for ORR electrocatalysis;these values are comparable to those for the best commercial Pt/C and all previously reported ORR catalysts in alkaline media.This two-in-one strategy is also successful with cicada and dragonfly wings,indicating that it is a universal,green,and cost-effective method for developing high-performance graphene-based materials. 展开更多
关键词 insect WINGS GRAPHENE GRAPHITE oxygen reduction reaction ELECTROCATALYSTS
Engineering porosity into trimetallic PtPdNi nanospheres for enhanced electrocatalytic oxygen reduction activity 预览
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作者 Chunjie Li You Xu +6 位作者 Yinghao Li Hongjie Yu Shuli Yin Hairong Xue Xiaonian Li Hongjing Wang Liang Wang 《绿色能源与环境:英文版》 2018年第4期352-359,共8页
Platinum(Pt)-based multi-metallic nanostructures show great promise as electrocatalysts for the oxygen reduction reaction(ORR) in fuel cell cathodes. Herein, we report a simple, one-step surfactant-directed synthetic ... Platinum(Pt)-based multi-metallic nanostructures show great promise as electrocatalysts for the oxygen reduction reaction(ORR) in fuel cell cathodes. Herein, we report a simple, one-step surfactant-directed synthetic strategy to directly synthesize tri-metallic PtPdNi mesoporous nanospheres(PtPdNi MNs) in a high yield. The synthesis could be accomplished in aqueous solution at mild reaction temperature(40C)without needing any organic solvent, yielding well-dispersed PtPdNi MNs with uniform shape and narrow size distribution. Benefitting from their unique mesoporous and highly open structure and tri-metallic composition, the as-synthesized PtPdNi MNs demonstrate superior catalytic activity and stability for ORR in acidic solution in comparison with PtPdNi nanodendrites(PtPdNi NDs), PtPd MNs and commercial Pt/C catalyst. The present approach may open a reliable path to the design of advanced electrocatalysts with desired performance. 展开更多
关键词 Tri-metallic PtPdNi MESOPOROUS structures NANOSPHERES Oxygen reduction reaction ELECTROCATALYSTS
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Recent advances in energy chemistry of precious-metal-free catalysts for oxygen electrocatalysis
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作者 Bin Wang Xiaoyang Cui +2 位作者 Jiaqi Huang Rui Cao Qiang Zhang 《中国化学快报:英文版》 SCIE CAS CSCD 2018年第12期1757-1767,共11页
The oxygen evolution reaction(OER) and oxygen reduction reaction(ORR) are coupled with various sustainable energy systems and are significant for the future energy scenario. Both of them suffer from sluggish kinetics,... The oxygen evolution reaction(OER) and oxygen reduction reaction(ORR) are coupled with various sustainable energy systems and are significant for the future energy scenario. Both of them suffer from sluggish kinetics, which calls for cost-effective and high-performance electrocatalysts to promote. The oxygen electrolysis of OER and ORR is heterogeneous reaction, which involves reactant and electron transfer, and a serial of complicate surface reactions. Both intrinsic catalyst activity and extrinsic physicochemical characters play a vital role in overall electrocatalytic reactivity. Herein. recent advances in rational design and effective construction of precious-metal-free materials are reviewed for OER and ORR, respectively, in the respects of electronic structure regulation, nanostructure tailor, and freestanding electrode fabrication. The reaction mechanism of OER and ORR are also updated. This review provides emerging energy chemistry concepts and materials chemistry strategies of electrocatalysts for OER and ORR, which is also enlightening for other energy conversion devices with targeted optimization. 展开更多
关键词 OXYGEN ELECTROCATALYSIS OXYGEN reduction REACTION OXYGEN evolution REACTION Metal-air batteries NANOSTRUCTURED ELECTROCATALYSTS
Ni和P微量掺杂的Pd基催化剂对碱性介质中乙醇电氧化性能的增强效应研究
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作者 朱婵 海洋 +1 位作者 赵志刚 阳耀月 《化学学报》 CSCD 北大核心 2018年第1期30-34,共5页
保证催化剂质量活性(通常以贵金属质量为计量)的基础上,减小催化剂中助催化剂的用量可有效降低燃料电池膜电极组(MEA)催化剂层的厚度,从而提高贵金属利用率和增大放电电压.于此,本文以微量Na H2PO2作为还原剂,适当调节合成溶液的碱... 保证催化剂质量活性(通常以贵金属质量为计量)的基础上,减小催化剂中助催化剂的用量可有效降低燃料电池膜电极组(MEA)催化剂层的厚度,从而提高贵金属利用率和增大放电电压.于此,本文以微量Na H2PO2作为还原剂,适当调节合成溶液的碱度,成功制备了助催化剂Ni和P的掺杂量分别低至0.2%(w)和0.05%(w)的三元碳载Pd-Ni-P纳米合金催化剂.所得催化剂在0.5 mol/L CH_3CH_2OH+1 mol/L Na OH溶液中的循环伏安表征显示,质量活性最高可达到2466 m A·mg-1 Pd,是商业化Pd/C催化剂的2.7倍;同时,计时电流法测试表明,该催化剂的稳定性相对于商业化催化剂提升了2.8倍.这说明所得低掺杂型Pd-Ni-P催化剂达到了上述设计要求.本工作可能为燃料电池高效低成本阳极催化剂设计制备提供新的思路. 展开更多
关键词 低掺杂合金 电催化剂 乙醇电氧化 碱性介质 性能增强
Fe-N-C类催化剂在碱性燃料电池中的研究进展
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作者 邓昕 陈亨权 +1 位作者 胡野 和庆钢 《电化学》 CSCD 北大核心 2018年第3期235-245,共11页
随着阴离子交换膜的出现、发展和应用,碱性燃料电池的优势日趋明显,针对碱性燃料电池的研究也更广泛而深刻.在碱性燃料电池中,除了其固有的对催化剂的高包容性和动力学优越性,阴离子交换膜让阴离子定向迁移,从而实现了很好的水相管理,... 随着阴离子交换膜的出现、发展和应用,碱性燃料电池的优势日趋明显,针对碱性燃料电池的研究也更广泛而深刻.在碱性燃料电池中,除了其固有的对催化剂的高包容性和动力学优越性,阴离子交换膜让阴离子定向迁移,从而实现了很好的水相管理,降低了电池中"水涝"的几率,也提供了更广阔的燃料选择空间.氧还原反应是碱性燃料电池中的重要部分,且其反应动力学相较于氢氧化反应缓慢.因此,选择并研制合适的阴极氧还原反应催化剂,是提高碱性燃料电池性能和促进燃料电池规模化使用的关键.Fe-N-C类催化剂因其在碱性条件下接近甚至优于Pt基催化剂的性能,被视为最有潜力替代Pt的非贵金属催化剂.本文从近5年来Fe-N-C类催化剂的合成方法、催化活性位点和氧还原反应机理以及在燃料电池中的应用三方面进行了综述. 展开更多
关键词 燃料电池 氧还原 Fe-N-C 催化剂
Facile synthesis and superior photocatalytic and electrocatalytic performances of porous B-doped g-C3N4 nanosheets
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作者 Qian Yan Gui-Fang Huang +3 位作者 Dong-Feng Li Ming Zhang An-Lian Pan Wei-Qing Huang 《材料科学技术学报:英文版》 SCIE EI CAS CSCD 2018年第12期2515-2520,共6页
As a low-cost visible-light-driven metal-free catalyst, graphitic carbon nitride(g-C3N4) has attracted increasing attention due to its wide applications for solar energy conversion, environmental purification,and orga... As a low-cost visible-light-driven metal-free catalyst, graphitic carbon nitride(g-C3N4) has attracted increasing attention due to its wide applications for solar energy conversion, environmental purification,and organic photosynthesis. In particular, the catalytic performance of g-C3N4 can be easily modulated by modifying morphology, doping, and copolymerization. Simultaneous optimization, however, has little been achieved. Herein, a facile one-pot strategy is developed to synthesize porous B-doped g-C3N4 nanosheets by using H3BO3 and urea as the precursor during thermal polymerization. The resultant B-doped g-C3N4 nanosheets retain the original framework of bulk g-C3N4, while induce prominently enhanced visible light harvesting and narrowing band gap by 0.32 eV compared to pure g-C3N4. Moreover, the adsorption capacity and photodegradation kinetics of methylene blue(MB) under visible light irradiation over B-doped g-C3N4 nanosheets can be improved by 20.5 and 17 times, respectively. The synthesized porous B-doped g-C3N4 nanosheets also exhibit higher activities than pure g-C3N4 as bifunctional electrocatalyst for both oxygen evolution reaction(OER) and oxygen reduction reaction(ORR). The enhanced catalyst performance of porous B-doped g-C3N4 nanosheets stems from the strong synergistic effect originating from the larger exposed active sites generated by the exfoliation of g-C3N4 into nanosheets and the porous structure, as well as the better conductivity owing to B-doping. This work provides a simple, effective, and robust method for the synthesis of g-C3N4-based nanomaterial with superior properties to meet the needs of various applications. 展开更多
关键词 B-DOPED g-C3N4 NANOSHEETS PHOTOCATALYSTS ELECTROCATALYSTS
固体聚合物氚电解浓缩系统的性能研究
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作者 刘佳煜 李华 +9 位作者 秦来来 邓珂 马玉华 张钦 杨果 马兆伟 卫飞 申淼 钱渊 刘卫 《核技术》 CSCD 北大核心 2018年第4期55-60,共6页
固体聚合物氚电解浓缩法是目前浓缩环境低氚水的主流方法,其性能评价的关键是能否获得较高的氚回收率。在电解体积浓缩倍数为常数时,氚分离系数决定了氚回收率的高低。为了提高氚电解浓缩系统的回收率,研究以分离系数为评价指标,从阴阳... 固体聚合物氚电解浓缩法是目前浓缩环境低氚水的主流方法,其性能评价的关键是能否获得较高的氚回收率。在电解体积浓缩倍数为常数时,氚分离系数决定了氚回收率的高低。为了提高氚电解浓缩系统的回收率,研究以分离系数为评价指标,从阴阳极材料、电解电流、电解水温度上优化固体聚合物氚电解浓缩系统。结果表明:在电解初始体积≥400 m L、电解装置电流15 A、电解水温度5°C、电解剩余体积≤25 m L的优化条件下,成功研制氚分离系数6.5以上、回收率≥65%的固体聚合物氚电解浓缩系统。 展开更多
关键词 固体聚合物氚电解浓缩 氚回收率 分离系数 电极催化剂 膜电极
Methanol oxidation in acidic and alkaline electrolytes using PtRuIn/C electrocatalysts prepared by borohydride reduction process 预览
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作者 Santos M.C.L. Nandenha J. +2 位作者 Ayoub J.M.S. Assumpao M.H.M.T. Neto A.O. 《燃料化学学报》 CSCD 北大核心 2018年第12期1462-1471,共10页
PtRuIn/C electrocatalysts(20%metal loading by weight)were prepared by sodium borohydride reduction process using H 2 PtCl 6·6H 2 O,RuCl 3·x H 2 O and InCl 3·x H 2 O as metal sources,borohydride as reduc... PtRuIn/C electrocatalysts(20%metal loading by weight)were prepared by sodium borohydride reduction process using H 2 PtCl 6·6H 2 O,RuCl 3·x H 2 O and InCl 3·x H 2 O as metal sources,borohydride as reducing agent and Carbon Vulcan XC72 as support.The synthetized PtRuIn/C electrocatalysts were characterized by X-ray diffraction(XRD),energy dispersive analysis(EDX),transmission electron microscopy(TEM),cyclic voltammetry(CV),chronoamperommetry(CA)and polarization curves in alkaline and acidic electrolytes(single cell experiments).The XRD patterns show Pt peaks are attributed to the face-centered cubic(fcc)structure,and a shift of Pt(fcc)peaks indicates that Ru or In is incorporated into Pt lattice.TEM micrographs show metal nanoparticles with an average nanoparticle size between 2.7 and 3.5 nm.Methanol oxidation in acidic and alkaline electrolytes was investigated at room temperature,by CV and CA.PtRu/C(50∶50)shows the highest activity among all electrocatalysts in study considering methanol oxidation for acidic and alkaline electrolyte.Polarization curves at 80℃show PtRuIn/C(50∶25∶25)with superior performance for methanol oxidation,when compared to Pt/C,PtIn/C and PtRu/C for both electrolytes.The best performance obtained by PtRuIn/C(50∶25∶25)in real conditions could be associated with the increased kinetics reaction and/or with the occurrence simultaneously of the bifunctional mechanism and electronic effect resulting from the presence of Pt alloy. 展开更多
关键词 BOROHYDRIDE reduction process PtRuIn/C ELECTROCATALYSTS METHANOL oxidation ACIDIC and ALKALINE electrolytes polarization CURVES
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