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Co9S8 nanowires@NiCo LDH nanosheets arrays on nickel foams towards efficient overall water splitting
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作者 Jingan Yan Ligang Chen Xin Liang 《科学通报:英文版》 SCIE EI CSCD 2019年第3期158-165,共8页
Water electrolysis is considered to be an effective way to fabricate hydrogen, and it is desirable to find the highly efficient, inexpensive and good durability bifunctional electrocatalysts for overall water splittin... Water electrolysis is considered to be an effective way to fabricate hydrogen, and it is desirable to find the highly efficient, inexpensive and good durability bifunctional electrocatalysts for overall water splitting.In this paper, we synthesis a unique structured catalyst that was composed by Co9S8 nanowires and nickel cobalt layered double hydroxide(NiCo-LDH) nanosheets. The ultrathin nanosheets decorated on the Co9S8 nanoarrays offer large specific surface area, numerous active edge sites and excellent electrical conductivity for fast electron transfer. Benefiting from this heterogeneous structure, the catalyst presents excellent catalytic performance in alkaline media. It requires 168 mV to reach current density of 10 mA/cm2 for HER and 278 m V to reach current density of 30 mA/cm2 for OER. When used as electrode in a homemade two-electrode system, it only needs t a voltage of 1.63 V to achieve current densities of 10 mA/cm2, which proves Co9S8@NiCo LDH/NF as a superior bifunctional catalyst for water splitting. 展开更多
关键词 Co9S8 NANOWIRE NiCo LDH Hydrogen EVOLUTION REACTION Oxygen EVOLUTION REACTION Water splitting
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)
MoS2协同过渡金属Co增强催化产氢性能 预览
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作者 郑波 陈文书 顾佳俊 《中国材料进展》 CAS CSCD 北大核心 2019年第2期106-109,115共5页
当今社会,能源危机与环境污染问题亟需解决,清洁环保且具有高能量密度的氢能被视为理想的能量载体。电催化分解水是一种有效且可持续的制氢方法。廉价且高效MoS2作为极具前景的产氢催化剂被广泛研究,其在酸性溶液中的催化效率已通过多... 当今社会,能源危机与环境污染问题亟需解决,清洁环保且具有高能量密度的氢能被视为理想的能量载体。电催化分解水是一种有效且可持续的制氢方法。廉价且高效MoS2作为极具前景的产氢催化剂被广泛研究,其在酸性溶液中的催化效率已通过多种工艺优化,然而其在碱性溶液中催化性能并没有得到有效提升。首先通过水热法合成了多孔的MoS2纳米片,然后提供了一种廉价便捷的电镀法,成功在MoS2表面复合Co等金属纳米颗粒,优化了MoS2在碱性溶液中的催化效率。实验表明Co-MoS2在1mol/LKOH中,在10mA·cm^-2的电流密度下过电势仅为186mV,Tafel斜率为81mV·dev^-1,大幅优于纯MoS2的催化性能,且表现出较好的稳定性。同时,Co-MoS2也表现出更好的催化析氧性能,在10mA·cm-2的电流密度下过电势由460降至360mV,这意味着Co-MoS2可进一步用于催化全水解反应。 展开更多
关键词 MOS2 协同作用 催化产氢(HER) 催化析氧(OER) 纳米工程
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Hollow Nanocages of NixCo1-xSe for Efficient Zinc–Air Batteries and Overall Water Splitting
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作者 Zhengxin Qian Yinghuan Chen +4 位作者 Zhenghua Tang Zhen Liu Xiufang Wang Yong Tian Wei Gao 《纳微快报:英文版》 CAS CSCD 2019年第2期140-156,共17页
Developing Earth-abundant,highly efficient,and anticorrosion electrocatalysts to boost the oxygen evolution reaction(OER),oxygen reduction reaction(ORR),and hydrogen evolution reaction(HER) for the Zn–air battery(ZAB... Developing Earth-abundant,highly efficient,and anticorrosion electrocatalysts to boost the oxygen evolution reaction(OER),oxygen reduction reaction(ORR),and hydrogen evolution reaction(HER) for the Zn–air battery(ZAB) and for overall water splitting is imperative.In this study,a novel process starting with Cu2O cubes was developed to fabricate hollow NixCo1-xSe nanocages as trifunctional electrocatalysts for the OER,ORR,and HER and a reasonable formation mechanism was proposed.The Ni0.2Co0.8Se nanocages exhibited higher OER activity than its counterparts with the low overpotential of 280 mV at 10 mA cm-2.It also outperformed the other samples in the HER test with a low overpotential of 73 mV at 10 mA cm-2.As an air–cathode of a self-assembled rechargeable ZAB,it exhibited good performance,such as an ultralong cycling lifetime of > 50 h,a high round-trip efficiency of 60.86%,and a high power density of 223.5 mW cm-2.For the application in self-made all-solid-state ZAB,it also demonstrated excellent performance with a power density of 41.03 mW cm-2 and an open-circuit voltage of 1.428 V.In addition,Ni0.2Co0.8Se nanocages had superior performance in a practical overall water splitting,in which only 1.592 V was needed to achieve a current density of 10 mA cm-2.These results show that hollow NixCo1-xSe nanocages with an optimized Ni-to-Co ratio are a promising cost-effective and high-efficiency electrocatalyst for ZABs and overall water splitting in alkaline solutions. 展开更多
关键词 NixCo1-xSe HOLLOW NANOCAGES Oxygen EVOLUTION REACTION Hydrogen EVOLUTION REACTION Rechargeable/all-solid-state zinc–air battery Overall water splitting
Hydrothermal Synthesized Co-Ni3S2 Ultrathin Nanosheets for Efficient and Enhanced Overall Water Splitting
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作者 JIAN Juan YUAN Long +5 位作者 LI He LIU Huanhuan ZHANG Xinghui SUN Xuejiao YUAN Hongming FENG Shouhua 《高等学校化学研究:英文版》 SCIE CAS CSCD 2019年第2期179-185,共7页
We used the one-step hydrothennal controlled synthesis method for Co-Ni3S2 ultrathin nanosheets grown directly on nickel foam(NF).The as-synthesized Co-Ni3S2/NF showed eiilianced activities in the hydrogen evolution r... We used the one-step hydrothennal controlled synthesis method for Co-Ni3S2 ultrathin nanosheets grown directly on nickel foam(NF).The as-synthesized Co-Ni3S2/NF showed eiilianced activities in the hydrogen evolution reaction(HER),oxygen evolution reaction(OER)and better overall water splitting(OWS)efficiency than the iin-doped Ni3S2/NF.the voltage of Co-Ni3S2/NF for OWS was only 1.58 V at the current density of 10 niA/cm^2 and with long time(>30 h)current output during the current-density(i-t)test.The good i-t pertonnance was also observed in both HER and OER processes.Additionally,the Co-Ni3S2/NF showed a large current density(>1A/cm^2)for both HER and OER.Wlien the current densities reached 100 and 1000 mA/cm^2,the required overpotentials tor Co-Ni3S2/NF were 0.35 and 0.75 V for OER and 0.30 and 0.85 V for HER.Therefore,after introducing Co,the activity of Ni3S2-based material was strongly enhanced. 展开更多
关键词 Co-Ni3S2/nickel tbam(NF) ULTRATHIN NANOSHEET Water splitting Hydrogen EVOLUTION REACTION Oxygen EVOLUTION REACTION
Cobalt and nitrogen codoped porous carbon as superior bifunctional electrocatalyst for oxygen reduction and hydrogen evolution reaction in alkaline medium
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作者 Xiaoxia Chen Xiangjun Zhen +6 位作者 Hongyu Gong Le Li Jianwei Xiao Zhi Xu Deyue Yan Guyu Xiao Ruizhi Yang 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第3期681-685,共5页
Cobalt and nitrogen codoped carbon materials(Co-N-C) were fabricated by pyrolysis of the mixture of poly(4-vinylpyridine) and cobalt chloride using SiO2 nanoparticles as hard template, which were the first transition ... Cobalt and nitrogen codoped carbon materials(Co-N-C) were fabricated by pyrolysis of the mixture of poly(4-vinylpyridine) and cobalt chloride using SiO2 nanoparticles as hard template, which were the first transition metal/nitrogen-codoped carbon bifunctional electrocatalyst derived from noncarbonizable polymer for ORR and HER. The as-made Co-N-C possessed hierarchical pore structure and high specific surface area, achieving excellent electrocatalytic performances for ORR and HER. Its ORR catalytic performances were comparable to those of Pt/C catalyst and its HER catalytic performances were superior to those of most doped carbon catalysts in KOH electrolyte. Moreover, its bifunctional electrocatalytic performances for ORR and HER were better than those of most bifunctional doped carbon catalysts in alkaline electrolyte. 展开更多
关键词 Carbon COBALT and NITROGEN Doped Oxygen reduction REACTION Hydrogen evolution REACTION
金属有机框架(MOFs)衍生物的制备及其在电催化方面的应用
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作者 朱静怡 梁风 +3 位作者 姚耀春 马文会 杨斌 戴永年 《稀有金属》 EI CAS CSCD 北大核心 2019年第2期186-200,共15页
金属有机框架(MOFs)是由金属离子或团簇和有机配体组成的、由中等强度的配位键连接起来的具有分子内孔隙的有机-无机杂化材料。MOFs具有比表面积大、孔隙度高、结构多样性及孔道表面可修饰等特点,因此, MOFs衍生材料在催化领域得到了广... 金属有机框架(MOFs)是由金属离子或团簇和有机配体组成的、由中等强度的配位键连接起来的具有分子内孔隙的有机-无机杂化材料。MOFs具有比表面积大、孔隙度高、结构多样性及孔道表面可修饰等特点,因此, MOFs衍生材料在催化领域得到了广泛的研究和应用。近年来,在电化学催化领域,大量的由MOFs衍生得到的碳纳米材料或纳米颗粒与碳的复合物被运用于电催化时表现出优异的催化性能。为了制备出具有不同催化功能且高效的MOFs衍生物催化剂,需要重点关注MOFs材料本身的特性(结构、杂原子掺杂等)与热处理条件(活化气氛、温度、时间和加热梯度)等条件对催化剂电催化性能的影响。因此,主要从不同金属中心离子的角度介绍了以MOFs为前驱体制备多孔碳纳米材料、纳米颗粒/碳复合物的方法及其在还原反应(ORR),析氢反应(HER)两大电化学催化方面的应用,并对MOFs衍生物催化剂未来的发展趋势进行了展望。 展开更多
关键词 金属有机框架 电化学催化剂 氧还原反应 析氢反应
多孔Ni-WC复合电极的制备及其在酸性溶液中的电催化析氢性能
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作者 杨余芳 杨环 +1 位作者 朱勋 梁昌金 《材料保护》 CAS CSCD 北大核心 2019年第3期40-46,共7页
目前,关于多孔Ni-WC电极的电催化析氢(HER)性能的报道较少。以多孔海绵镍为基体,采用复合电沉积制备多孔Ni-(WC)x复合电极。运用扫描电镜(SEM)和X射仪线衍射仪(XRD)表征电极的表面形貌和微观结构,通过阴极极化、电化学阻抗(EIS)、循环... 目前,关于多孔Ni-WC电极的电催化析氢(HER)性能的报道较少。以多孔海绵镍为基体,采用复合电沉积制备多孔Ni-(WC)x复合电极。运用扫描电镜(SEM)和X射仪线衍射仪(XRD)表征电极的表面形貌和微观结构,通过阴极极化、电化学阻抗(EIS)、循环伏安、计时电流法研究多孔Ni-(WC)x电极在0.5 mol/L H2SO4溶液中的电催化析氢性能。结果表明:与多孔基体Ni电极相比,多孔Ni-(WC)x电极具有较低的析氢过电位、较低的电化学反应阻抗、较小的表观活化能以及较大的交换电流密度;随着镀液中WC浓度的升高,所制备的多孔Ni-(WC)x电极的电催化析氢活性增强,其中Ni-(WC)40电极的表观交换电流密度是多孔Ni基体电极的966.7倍,其表观活化能为5.95 kJ/mol,并具有较好的耐蚀性和析氢稳定性。 展开更多
关键词 多孔Ni-(WC)x 复合电极 海绵镍 电催化 析氢
Enhancement of the hydrogen evolution performance by finely tuning the morphology of Co-based catalyst without changing chemical composition
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作者 Wenling Gu Liuyong Hu +2 位作者 Changshuai Shang Jing Li Erkang Wang 《纳米研究:英文版》 SCIE EI CAS CSCD 2019年第1期191-196,共6页
Transition-metal phosphides, as the promising alternatives to noble metal catalysts, have been widely used as efficient electrocatalysts for hydrogen evolution reaction (HER). In this work, three kinds of cobalt-8-hyd... Transition-metal phosphides, as the promising alternatives to noble metal catalysts, have been widely used as efficient electrocatalysts for hydrogen evolution reaction (HER). In this work, three kinds of cobalt-8-hydroxyquinoline (Coqx) with different size and nanostructures are synthesized by varying the hydrothermal conditions, which was named as Coqx-L, Coqx-M and Coqx-S according to the decreased size. Accordingly, the CoxP/NC with three different size nanostructures (CoxP/NC-L, CoxP/NC-M and CoxP/NC-S) are obtained by the sequential carbonization and phosphidation of Coqx. The X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) results imply the identical chemical composition in these catalysts with different morphologies. Thus, systematic study is carried out to reveal the relationship between catalytic performance and morphologies of materials with the same chemical composition. The experimental result indicates that the morphology of Cc)xP/NC plays a crucial role on the surface area and electron transfer. Finally, the catalyst of CoxP/NC-S with the smallest size nanostructrue exhibits the best HER performance with a low overpotential at current density of 10 mA/cm^2 (n = 56.9 and 115.6 mV) and a small Tafel slope (52.3 and 69.3 mV/dec) in both 0.1 M HCIO4 and 1.0M KOH as well as long-term stability. 展开更多
关键词 ELECTROCATALYST hydrogen evolution reaction TRANSITION-METAL PHOSPHIDES
Nickel cobalt phosphide with three-dimensional nanostructure as al highly efficient electrocatalyst for hydrogen evolution reaction in both I acidic and alkaline electrolytes
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作者 Bo Ma Zhengchun Yang +1 位作者 Yantao Chen Zhihao Yuan 《纳米研究:英文版》 SCIE EI CAS CSCD 2019年第2期375-380,共6页
Transition metal phosphides (TMPs) are promising candidates for noble metal free electrocatalysts in water splitting applicati ons. In this work, we prese nt the facile syn thesis of nickel cobalt phosphide electrocat... Transition metal phosphides (TMPs) are promising candidates for noble metal free electrocatalysts in water splitting applicati ons. In this work, we prese nt the facile syn thesis of nickel cobalt phosphide electrocatalyst with three-dime nsional nano structure (3D-NiCoP) on the nickel foam, via hydrothermal reaction and phosphorization. The as-prepared electrocatalyst exhibits an excellent activity for hydrogen evolution reaction (HER) in both acidic and alkaline electrolytes, with small overpotentials to drive 10 mA/cm^2 (80 mV for 0.5 M H2SO4, 105 mV for 1 M KOH), small Tafel slopes (37 mV/dec for 0.5 M H2SO4, 79 mV/dec for 1 M KOH), and satisfying durability in long-term electrolysis. 3D-NiCoP also shows a superior HER activity compared to single metal phosphide, such as cobalt phosphide and nickel phosphide. The outstanding performa nee for HER suggests the great pote ntial of 3D-NiCoP as a highly efficient electrocatalyst for water splitting technology. 展开更多
关键词 NICKEL COBALT PHOSPHIDE water splitting hydrogen evolution reaction ELECTROCATALYST
激光直写制备三维自支撑NiS2/MoS2复合电催化剂应用于碱性和中性电解水制氢 预览
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作者 程鹏飞 冯婷 +2 位作者 刘紫薇 吴德垚 杨静 《催化学报》 SCIE EI CAS CSCD 北大核心 2019年第8期1147-1152,共6页
电催化析氢反应(HER)是一种有前途和可持续的制氢途径.到目前为止,所报道的高性能催化剂如铂和其他贵金属基催化剂大多只能在酸性或碱性条件下展现出优异的HER催化活性,而且这些贵金属储量稀少,催化剂制备成本高昂.此外,考虑到电解设备... 电催化析氢反应(HER)是一种有前途和可持续的制氢途径.到目前为止,所报道的高性能催化剂如铂和其他贵金属基催化剂大多只能在酸性或碱性条件下展现出优异的HER催化活性,而且这些贵金属储量稀少,催化剂制备成本高昂.此外,考虑到电解设备和环境保护的要求,在中性介质中寻找高效的HER电催化剂是潜在的发展方向,但也需要克服中性电解质中欧姆损失较大、电子密度较低等问题.因此,开发低成本、应用广泛的电催化剂是今后实现制氢产业化的必然选择.根据已有研究,具有不同结构的双金属硫化物杂化物由于两种金属硫化物成分所提供的可靠且充分的氧化还原活性位点,显示出其具有吸引力的活性.此外,由于丰富的活性位点和重新配置的电子结构,复合材料两组分之间的界面产生协同效应会进一步增强催化剂的HER催化活性.之前的工作已经在同样材料体系中获得了较好的催化性能,但是在宽pH条件下的HER催化性能却不如人意.因此, NiS2与MoS2界面结构的优化是进一步提高其在宽酸碱度电解质中活性的关键.本文使用毫秒激光直写法在镍泡沫上合成了三维(3D)自支撑的NiS2/MoS2异质结构,并将其直接用作电解水析氢反应电极,后者在碱性和中性电解质中都表现出了优异的HER活性.毫秒激光直写法具有瞬时高温和快速冷却的特点,常用于纳米材料的制备.毫秒激光作用于溶液中的泡沫镍时,由于瞬间高温使其气化,与溶液中的离子、分子等组成了等离子体,随后借助液体环境的急速冷却限制效应,这团高温混合物在靶材表面原位生长出NiS2/MoS2纳米复合催化剂.通过物相表征,发现NiS2/MoS2异质结构是由高度分散的小尺寸NiS2纳米粒子和MoS2纳米片组成,这些纳米片具有较大的比表面积以及大量NiS2与MoS2之间的界面.借助宏观XPS表征,我们可以确认在NiS2/MoS2异质结构的界面处存 展开更多
关键词 异质结构 电解水制氢 激光直写
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Sisyphus effects in hydrogen electrochemistry on metal silicides enabled by silicene subunit edge
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作者 Zechao Zhuang Yong Li +7 位作者 Jiazhao Huang Zilan Li Kangning Zhao Yunlong Zhao Lin Xu Liang Zhou Lyudmila V.Moskaleva Liqiang Mai 《科学通报:英文版》 SCIE EI CSCD 2019年第9期617-624,共8页
Nonmetal elements strictly govern the electrochemical performance of molybdenum compounds.Yet,the exact role played by nonmetals during electrocatalysis remains largely obscure.With intermetallic MoSi2comprising silic... Nonmetal elements strictly govern the electrochemical performance of molybdenum compounds.Yet,the exact role played by nonmetals during electrocatalysis remains largely obscure.With intermetallic MoSi2comprising silicene subunits,we present an unprecedented hydrogen evolution reaction(HER)behavior in aqueous alkaline solution.Under continuous operation,the HER activity of MoSi2shows a more than one order of magnitude improvement in current density from 1.1 to 21.5 mA cmà2at 0.4 V overpotential.Meanwhile,this activation behavior is highly reversible,such that voltage withdrawal leads to catalyst inactivation but another operation causes reactivation.Thus,the system shows dynamics strikingly analogous to the legendary Sisyphus’labor,which drops and recovers in a stepwise manner repeatedly,but never succeeds in reaching the top of the mountain.Isomorphic WSi2behaves almost the same as MoSi2,whereas other metal silicides with silicyne subunits,including CrSi2and TaSi2,do not exhibit any anomalous behavior.A thin amorphous shell of MoSi2is observed after reaction,within which the Si remains partially oxidized while the oxidation state of Mo is basically unchanged.First-principles calculations further reveal that the adsorption of hydroxide ions on silicene subunit edges and the subsequent Si vacancy formation in MoSi2jointly lead to the anomalous HER kinetics of the adjacent Mo active centers.This work demonstrates that the role of nonmetal varies dramatically with the electronic and crystallographic structures of silicides and that silicene structural subunit may serve as a promoter for boosting HER in alkaline media. 展开更多
关键词 Sisyphus effect ELECTROCHEMISTRY Metal SILICIDES SILICENE SUBUNIT HYDROGEN evolution reaction
In situ growth of N-doped carbon coated CoNi alloy with graphene decoration for enhanced HER performance 预览
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作者 Linlin Chen Saisai Yang +3 位作者 Kun Qian Wei Wei Cheng Sun Jimin Xie 《能源化学:英文版》 SCIE EI CAS CSCD 2019年第2期129-135,共7页
Non-noble metal-based catalysts,especially stable ones,have gained increasing attentions in the field of electronically catalytic hydrogen evolution reaction(HER).In this work,an N-doped carbon confined Co–Ni alloy w... Non-noble metal-based catalysts,especially stable ones,have gained increasing attentions in the field of electronically catalytic hydrogen evolution reaction(HER).In this work,an N-doped carbon confined Co–Ni alloy with reduced graphene oxide(rGO) decoration(CoNi@N-C/rGO) was fabricated for HER.The prepared catalyst exhibited excellent HER activity in an acidic electrolyte(Tafel slope of ~133.7 m V).The results showed that the enhanced HER performance of the nanostructures is attributed to the chemical and electronic synergic effect between the confined Co–Ni alloy and r GO.Stability tests,realized via longterm potential cycles and extended electrolysis,provided the confirmation of the exceptional durability of the catalyst,which originated from the confining effect of the N-doped carbon shell.This versatile method provides a strategy for designing stable non-precious metal electrocatalysts confined by carboncoating. 展开更多
关键词 Metal alloys N-DOPED CARBON Reduced GRAPHENE OXIDES Hydrogen evolution reaction
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含双金属碳化物复合材料的制备及其析氢性能研究 预览
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作者 高静 雷薇 《浙江工业大学学报》 CAS 北大核心 2019年第3期348-354,共7页
双金属碳化物因具有高效的电子传输速率和稳定的电子结构而被认为是潜在的电化学析氢催化剂,但其制备条件非常苛刻,通常需要将多种反应物在高温下碳化。设计性地采用含过渡金属的多酸有机-无机杂化物作为前驱体,利用有机胺与多酸的协同... 双金属碳化物因具有高效的电子传输速率和稳定的电子结构而被认为是潜在的电化学析氢催化剂,但其制备条件非常苛刻,通常需要将多种反应物在高温下碳化。设计性地采用含过渡金属的多酸有机-无机杂化物作为前驱体,利用有机胺与多酸的协同作用,在较低温度下经一步煅烧即可成功制备碳包覆的含双金属碳化物Co6W6C的复合材料。电化学测试表明:由于Co-W双金属的协同效应,该复合材料在酸碱条件下均表现出较好的析氢活性。这一双金属碳化物的合成策略简单普适,对类似材料的制备具有重要的参考价值。 展开更多
关键词 Co6W6C 杂多酸 析氢反应 电催化
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Facile synthesis of molybdenum carbide nanoparticles in situ decorated on nitrogen-doped porous carbons for hydrogen evolution reaction 预览
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作者 Jin-Tao Ren Yue-Jun Song Zhong-Yong Yuan 《能源化学:英文版》 SCIE EI CAS CSCD 2019年第5期78-84,共7页
Molybdenum-based electrocatalysts are promising candidates of platinum (Pt)-based materials in electrocatalyzing hydrogen evolution reaction (HER), due to their cost-efficient and resembled electronic properties. Repo... Molybdenum-based electrocatalysts are promising candidates of platinum (Pt)-based materials in electrocatalyzing hydrogen evolution reaction (HER), due to their cost-efficient and resembled electronic properties. Reported herein is the preparation of molybdenum carbide nanoparticles uniformly decorated on nitrogen-modified carbons (Mo2C/NC) through the carbonization of Mo-based polymers under hydrogen atmosphere by using poly(p-phenylenediamine) and ammonium heptamolybdate polymer analogue as precursors. And the molybdenum nitride nanoparticles loaded on porous N-doped carbons (Mo2N/NC) are also fabricated by calcination the polymer precursors in nitrogen gas. The Mo2C/NC shows more excellent electrocatalytic activity than Mo2N/NC in 0.5 M H2SO4, together with robust long-term durability. The well-crystalline nanoparticles and the increased electron conductivity are the main characters responded for the high catalytic efficiency of the fabricated electrocatalysts. This easily fabrication procedure may provide a facile route to prepare non-noble metal carbide/nitride catalysts featuring wellengineered structural and textural peculiarities for realistic energy conversion system. 展开更多
关键词 MOLYBDENUM CARBIDE MOLYBDENUM NITRIDE NITROGEN-DOPED carbon Hydrogen evolution reaction ELECTROCATALYSIS
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N和Co修饰的多孔碳催化剂的制备及电催化析氢性能研究 预览
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作者 宋丹丹 崔丽莉 《长春理工大学学报:自然科学版》 2019年第2期125-130,共6页
首先利用溶剂热法制备出两种不同的金属有机框架MOFs,将两种不同的MOFs分别与石墨烯材料复合,得到ZnCo-MOF/Gr以及Co-MOF/Gr,经过高温热解后形成碳层包裹的钴纳米颗粒负载在N掺杂的多孔碳材料上(Co-N-C-T以及Co/N/C),通过XRD、XPS、SEM... 首先利用溶剂热法制备出两种不同的金属有机框架MOFs,将两种不同的MOFs分别与石墨烯材料复合,得到ZnCo-MOF/Gr以及Co-MOF/Gr,经过高温热解后形成碳层包裹的钴纳米颗粒负载在N掺杂的多孔碳材料上(Co-N-C-T以及Co/N/C),通过XRD、XPS、SEM和TEM等手段对其进行了结构和形貌表征。结果表明所制备的Co-N-C-900继承了MOFs的高比表面积的特性,尺寸均一,其比表面积高达488.73m^2g^-1和具有多级孔结构、高浓度的催化活性位点(N和Co的原子含量为3.77%和1.26%)。并通过一系列电化学测试手段对材料的电催化析氢(HER)性能进行了评估。结果表明Co-N-C-900在酸性和碱性条件下都表现出优异的HER催化性能,在不同电解质中的起始电位最正,塔菲尔斜率最小,与Pt/C最为接近。在经历了1000次的循环伏安(CV)测试后,测得的线性伏安曲线(LSV)与初始LSV基本重合,表明Co-N-C-900具有较好的稳定性。 展开更多
关键词 溶剂热法 MOFS 石墨烯 析氢反应
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石墨烯负载超薄二硫化钼杂化材料的电催化析氢性能 预览
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作者 郭树旺 高占勇 +2 位作者 宋金玲 布林朝克 张邦文 《无机化学学报》 SCIE CAS CSCD 北大核心 2019年第7期1195-1202,共8页
以磷钼酸和L-半胱氨酸作为前驱体,还原氧化石墨烯作为载体,采用水热法一步合成了超薄二硫化钼/还原氧化石墨烯杂化材料(UT-MoS2/rGO)。作为电催化析氢(HER)非贵金属催化剂,对其结构特征和在0.5mol·L-1H2SO4溶液中氧化还原反应的催... 以磷钼酸和L-半胱氨酸作为前驱体,还原氧化石墨烯作为载体,采用水热法一步合成了超薄二硫化钼/还原氧化石墨烯杂化材料(UT-MoS2/rGO)。作为电催化析氢(HER)非贵金属催化剂,对其结构特征和在0.5mol·L-1H2SO4溶液中氧化还原反应的催化性能进行表征。结果显示,得益于UT-MoS2暴露的丰富活性位点、导电rGO片的稳定支撑以及MoS2与rGO的良好结合,UT-MoS2/rGO显示了优异的电催化性能。其起始过电势为-66mV;电流密度为-10mA·cm^-2时过电势为-145mV,Tafel斜率为42.9mV·dec^-1;交流阻抗为0.76Ω;在0.1~0.2V范围内循环伏安测试1000次后,其催化活性仍能保持98%。 展开更多
关键词 水热合成 MOS2 石墨烯 电催化 析氢反应
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盐封后碳化钼电催化剂的制备及其氢析出性能 预览
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作者 林舟 申琳璠 +3 位作者 瞿希铭 张俊明 姜艳霞 孙世刚 《物理化学学报》 SCIE CAS CSCD 北大核心 2019年第5期523-530,共8页
碳化钼具有低廉的价格、优越的催化性能以及良好的稳定性而被人们认为是极好的可以替代Pt等贵金属的氢析出反应(HER)催化剂。本工作采用钼酸钠和2,6-二氨基吡啶为反应原料,之后不断进行盐封的过程直到前驱体被紧紧包覆在NaCl的晶格中,... 碳化钼具有低廉的价格、优越的催化性能以及良好的稳定性而被人们认为是极好的可以替代Pt等贵金属的氢析出反应(HER)催化剂。本工作采用钼酸钠和2,6-二氨基吡啶为反应原料,之后不断进行盐封的过程直到前驱体被紧紧包覆在NaCl的晶格中,最后置于惰性气氛下煅烧即可制得盐封后碳化钼。本工作采用了扫描电子显微镜(SEM)、透射电子显微镜(TEM)、能量色散x射线光谱(EDS)、X射线衍射(XRD)以及X射线光电子能谱(XPS)等技术对盐封后碳化钼的形貌、组成以及晶体结构进行了表征。结果表明盐封后的产物形貌并不均一,其中包括纳米颗粒及纳米棒。比较Mo2C/SS与Mo2C的TEM图,可以发现盐封后Mo2C的尺寸变小,表明盐封的方法可以有效地避免颗粒的团聚。根据产物的氮气吸脱附等温线得到的催化剂的Brunauer-Emmett-Teller (BET)比表面积,盐封后Mo2C的BET表面积由2.55提高至8.14m^2·g^-1,可以证明盐封过程中孔的生成。EDS、XRD及XPS分析的结果表明盐封后的产物是斜方晶系的Mo2C,并且表面由于被氧气氧化而带有氧化钼。结合XPS和周转率(TOF)数计算的结果,可以说明盐封过程中孔的形成有助于暴露更多活性位点,然而同时也扩大了与氧气的接触面积,催化剂表面形成的氧化钼的含量也增多。因此,催化剂表面活性中心即碳化钼所占的比例降低。另一方面,氧化钼的法拉第反应产生的赝电容会与碳化钼催化剂的双电层电容叠加,导致得到的比容量数值偏大。而氧化钼的赝电容效应对Mo2C/SS催化剂的影响是更显著的,因此盐封后的TOF数降低。同Mo2C相比, Mo2C/SS展现出更高的HER质量活性的原因可归结如下:(1)盐封过程中大量孔的形成有助于提高产物的BET表面积并暴露出更多的活性位点;(2)盐封后的多孔结构和较大的表面积有利于传质传荷;(3)盐封后碳化钼的Tafel斜率由145降至88mV·dec^-1。总的来� 展开更多
关键词 碳化钼 氢析出反应 盐封 活性位点 电催化
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一步水热法合成MoS2/Ni Foam复合材料及电催化析氢性能研究 预览
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作者 肖涤非 蒋传海 +3 位作者 肖果蕾 王德 郭小玲 徐彦宾 《鲁东大学学报:自然科学版》 2019年第1期46-50,共5页
以原料丰富、成本低并且催化性能优异的析氢(HER)催化剂代替贵金属Pt基催化剂,并应用于电催化分解水具有重要意义.以仲钼酸铵((NH4)6Mo7O24·4H2O)、硫脲(H2NCSNH2)、泡沫镍(NiFoam)以及盐酸羟胺(NH2OH·HCl)为原料,采用水热法... 以原料丰富、成本低并且催化性能优异的析氢(HER)催化剂代替贵金属Pt基催化剂,并应用于电催化分解水具有重要意义.以仲钼酸铵((NH4)6Mo7O24·4H2O)、硫脲(H2NCSNH2)、泡沫镍(NiFoam)以及盐酸羟胺(NH2OH·HCl)为原料,采用水热法制备了纳米花状MoS2材料,并通过一步水热法在泡沫镍基底上垂直生长了层状及类花状结构的二硫化钼(MoS2),合成了MoS2/NiFoam复合材料,利用X射线粉末衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)等表征手段对样品的物相和形貌进行了详细的表征分析.在1MKOH中对MoS2/NiFoam复合材料进行电催化析氢性能研究,结果显示:NiFoam,MoS2之间的协同催化作用、电耦合以及暴露于表面的丰富的边缘活性位点使得MoS2/NiFoam复合材料展现出优异的电催化析氢性能,并明显优于单相MoS2纳米材料,在电流密度10mA·cm^-2下析氢过电位仅为118mV,经过200h连续电解仍能保持优异的电催化析氢性能. 展开更多
关键词 二硫化钼 电催化 析氢反应 一步水热法 纳米复合材料
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直接合成双掺杂N-MoP/N-CNT及其高效析氢催化性能
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作者 张俊涛 眭瑞 +4 位作者 薛延荣 王兴栋 裴加景 梁鑫 庄仲滨 《中国科学:材料科学(英文版)》 CSCD 2019年第5期690-698,共9页
清洁氢能源是未来发展的重要方向,因此开发高效廉价的析氢材料尤为重要.掺杂的磷化物作为一种优异的析氢材料得到了广泛的关注.本文提出了一种将氮原子同时掺杂在磷化物催化剂和载体上的新的合成方法.在热处理的过程中,利用次磷酸铵(NH4... 清洁氢能源是未来发展的重要方向,因此开发高效廉价的析氢材料尤为重要.掺杂的磷化物作为一种优异的析氢材料得到了广泛的关注.本文提出了一种将氮原子同时掺杂在磷化物催化剂和载体上的新的合成方法.在热处理的过程中,利用次磷酸铵(NH4H2PO2)分解产生的氨和磷化氢气体与前驱体进行反应,一步得到双掺杂的氮掺杂碳纳米管负载氮掺杂磷化钼催化剂(N-MoP/N-CNT).该催化剂展现出了良好的析氢反应活性,当电流密度为10 mA cm^-2时,过电势只有103±5 mV,明显低于MoP纳米颗粒的过电势(243 mV).催化活性的提升主要来自掺氮带来的电子效应以及协同效应.该催化剂在电解水产氢方面具有应用前景. 展开更多
关键词 直接合成 双掺杂 析氢 催化性能 钼催化剂 反应活性 磷化氢气体 磷化物
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