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41.
Engineering oxygen vacancy-rich Co3O4 nanowire as high-efficiency and durable bifunctional electrocatalyst for overall alkaline water splitting
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A novel kind of vacancy-rich nanowire arrays were prepared by reducing rough Co3O4 nanowires with NaBH4 solution on 3D nickel foam at room temperature for overall water splitting. Co3O4/NF treated by NaBH4 for 10 min was highly active for oxygen evolution reaction (OER) and simultaneously efficient for hydrogen evolution reaction (HER) with the need of the overpotentials of 240 and 132 mV to drive 10 mA·cm-2 in alkaline media, respectively. Furthermore, the electrocatalysts as both cathode and anode in a two-electrode system presented excellent durability for over 60 h at 10 mA·cm-2, maintaining the cell voltage of merely 1.63 V. This work provides new methods and ideas for the preparation of transition metal oxide bifunctional electrocatalysts rich in oxygen vacancies. 相似文献
42.
Preparation and lithium storage properties of Mo2N quantum dots@nitrogen-doped graphene composite
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WANG Lixia ZHANG Zhenhua LI Lei ZHANG Linsen FANG Hua SONG Yanhua LI Xiaofeng 《化工学报》2021,71(12):5854-5862
To improve the electrochemical lithium storage performance of molybdenum nitrides, Mo2N quantum dots@nitrogen-doped graphene oxide sponge (Mo2N-QDs@Ngs) was prepared by hydrothermal reaction, freeze-drying and calcination in H2/N2 mixture with ammonium molybdate ((NH4)Mo7O24·4H2O), hexamethylenetetramine (C6H12N4) and graphene oxide (GO) as raw materials. The effect of GO content on the electrochemical lithium storage performance was investigated. The transmission electron microscope (TEM) results show that the size of the prepared Mo2N quantum dots is about 2—5 nm, and the Mo2N quantum dots are uniformly distributed on the surface of nitrogen-doped graphene. The electrochemical test results show that when the GO content is 30%, the prepared Mo2N-QDs@Ngs-30 has the best electrochemical lithium storage performance, which has 699 mA·h·g-1 specific capacity at the current density of 0.1 A·g-1, and has 286 mA·h·g-1 specific capacity even at the current density of 2 A·g-1. 相似文献
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45.
Electrochemical properties of some cobalt antimonides as anode materi-als for lithium- ion batteries
ZHAO Xinbing CAO Gaoshao ZHANG Lijuan and XIE JianDepartment of Materials Science Engineering Zhejiang University Hangzhou China 《稀有金属(英文版)》2003,22(4)
Some cobalt antimonides have been prepared and studied as the candidate anode materials for lithium ion batter-ies. Reversible capacities of 424,423 and 546 mA·h·g-1 were measured at the first cycle for as-solidified CoSb2, CoSb3 and annealed CoSb3 respectively. A low lithium ions diffusion coefficient in the order of 10-16 m2·s-1 was estimated from the coulometric titration measurements in the annealed CoSb3 electrode. It was found that the electrochemical properties of fine powders are significantly better than coarse powders. However the SEM picture shows that the nano-sized CoSb3 powders gathered to larger granules, which worsens somewhat the capacity retention of the nano-sized materials, although the volume capacities of the annealed and ball milled CoSb3 remain near twice of that of graphite after 50 cycles. 相似文献
46.
The cyclic voltammetry and the potential-time curve after galvanostatic electrolysis were used to study the electrode processes of Cu(Ⅱ) in CH3OH solution and DMSO solution. The electroreduction of Cu(Ⅱ) to Cu on a Pt electrode proceeds in two steps: Cu(Ⅱ) + e = Cu(Ⅰ); Cu(Ⅰ) + e = Cu. The reduction potential of Cu(Ⅱ) in DMSO solution is more negative than that in CH3OH solution, and the diffusion coefficient of Cu(Ⅱ) ion in DMSO solution is larger than that in CH3OH solution because the polarity of DMSO is larger than that of CH3OH observably and has a stronger solvating power. 相似文献
47.
应用电化学测试手段,针对20、2Cr13、QAl 9-2、QA
l 10-3-15和QAl 10-4-4五种材料试件,分别测定了它们在NaCl溶液中的腐蚀电位及与QAl 9-2偶接时的电偶腐蚀电流的变化.并对几种铝青铜材料和QAl 9-2构成的摩擦副进行了摩擦磨损性能分析.结果表明,铝青铜材料的抗腐蚀性比钢好.其中QAl 10-4-4的腐蚀电位最为偏正,但它与QAl 9-2配副会对QAl 9-2产生较大的阳极电偶腐蚀;QAl 9-2与QAl 9-2相配时的电偶腐蚀最小,但其摩擦相溶性最差;而QAl 9-2与QAl 10-3-15材料副的抗电偶腐蚀能力和摩擦相溶性均佳. 相似文献
48.
Fe2 + 的氧化在细菌浸矿过程中具有重要作用 ,细菌浸铜过程中 ,Cu2 + 的存在对T .f菌的生长代谢和其氧化Fe2 + 的能力有一定影响。制备了T .f菌修饰碳粉粉末微电极 ,研究了Cu2 + 存在下Fe2 + 在T .f菌修饰粉末微电极上氧化的电化学反应机理 ,并测定了相应的电极过程动力学参数。循环伏安研究表明 ,Cu2 + 的存在不影响Fe2 + 在T .f菌修饰粉末微电极上的氧化反应的可逆性。对电极稳态及暂态过程研究表明 ,当Cu2 + 浓度在 12mmol/L以下时 ,Cu2 + 的存在不会抑制Fe2 + 在T .f菌修饰粉末微电极上的氧化 ,适量Cu2 + 加强T .f菌氧化Fe2 +的作用是在于其加快了电荷传递速率 相似文献
49.
Synthesis and thermal decomposition kinetics of LiNiO2 总被引:1,自引:1,他引:1
A layered LiNiO2 with high crystallinity was synthesized by sintering the finely prepared mixture of lithium hydroxide and nickel hydroxide in the oxygen atmosphere. The electro-chemical properties of LiNiO2 show that it has a reversible capacity of more than 168mA*h*g-1. It was found that with increasing temperature, LiNiO2 decomposed in air followed with three reaction stages, the apparent activation energies were 747.18±1.0kJ*mol-1, 932.46±1.0kJ*mol-1 and 1126.97±1.0kJ*mol-1 respectively, and the kinetic equations of the three reaction stages were obtained. 相似文献
50.
综述了Mo在不同溶液中的电化学行为、电池作用腐蚀
行为,并从技术的角度总结了它在各种碱性溶液、酸性溶液、无机盐溶液以及海水中的耐蚀性能.最后对研究工作进行了展望. 相似文献