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61.
Alkaline direct alcohol fuel cells 总被引:1,自引:0,他引:1
The faster kinetics of the alcohol oxidation and oxygen reduction reactions in alkaline direct alcohol fuel cells (ADAFCs), opening up the possibility of using less expensive metal catalysts, as silver, nickel and palladium, makes the alkaline direct alcohol fuel cell a potentially low cost technology compared to acid direct alcohol fuel cell technology, which employs platinum catalysts. A boost in the research regarding alkaline fuel cells, fuelled with hydrogen or alcohols, was due to the development of alkaline anion-exchange membranes, which allows the overcoming of the problem of the progressive carbonation of the alkaline electrolyte. This paper presents an overview of catalysts and membranes for ADAFCs, and of testing of ADAFCs, fuelled with methanol, ethanol and ethylene glycol, formed by these materials. 相似文献
62.
?ükriye Ulubay Karabibero?luLevent Pelit Buket GelmezZekerya Dursun 《International Journal of Hydrogen Energy》2011,36(20):12678-12685
The electrochemical oxidation of borohydride was investigated by using various ad-atom modified Au(111) electrodes in alkaline media in comparison to Au(111) single crystal, polycrystalline Au, Pt and Zn electrodes. The catalytic activity of gold towards borohydride oxidation has tended to increase in more alkaline media as reflected in the oxidation peak in the concentration range of NaOH (0.01-2.0 M) studied. Additional shift on the oxidation peak potential of borohydride on Pt and Zn ad-atom modified Au(111) electrodes was observed for both ad-atom modified electrodes to more negative potentials compared to that of bare electrodes, respectively. The ad-atom modified Au(111) electrodes surfaces do not only provide a superior electrical contact, but also accelerates electron transfer as proven by the increase in peak current and positive shift in the peak potential. 相似文献
63.
《International Journal of Hydrogen Energy》2019,44(14):7402-7413
Here, phase transformation and electrochemical characteristics of non-stoichiometry La4MgNix (x = 16, 17 and 18) hydrogen storage alloys were studied. It is found that after annealed at 1223 K for 24 h, the minor AB3 and AB5 phases in La4MgNi16 alloy transform into A2B7 phase by a peritectic reaction and the La4MgNi16 alloy shows a A2B7 single phase structure. Double phase structures of A2B7/A5B19 are obtained in La4MgNi17 and La4MgNi18 alloys after annealed at the same condition. The abundance of A5B19 phase increases as x increases, indicating the increasing x value contributes to the formation of A5B19 phases. Electrochemical studies show that the maximum discharge capacity and capacity retention at the 100th charge/discharge cycles (S100) of A2B7 single phase La4MgNi16 alloy is 373 mAh g−1 and 78.4%, respectively. The appearance of A5B19 (minor) phase in the La4MgNi17 alloy makes a remarkable improvement in the discharge capacity from 373 mAh g−1 to 388.8 mAh g−1, as well as the S100 from 78.4% to 90.1%. It is believed that the LaMgNi-based alloy with the A2B7(main)/A5B19(minor) phase structure possesses the good overall electrochemical properties and is applicable to the high-power and long-cycle life negative electrode material for nickel metal hydride batteries. 相似文献
64.
就L-半胱氨酸盐酸电化学生产工艺的工业化进行了讨论,并分布了工业化实验一些研究成果。 相似文献
65.
R. Chaiyont C. Badoe C. Ponce de León J. L. Nava F. J. Recio I. Sirés P. Herrasti F. C. Walsh 《化学工程与技术》2013,36(1):123-129
A film of iridium and tin dioxides doped with antimony oxide (IrO2‐SnO2‐Sb2O5) was deposited onto Ti mesh and plate substrates by the Pechini method. The electrode surface morphology and composition were characterized by SEM‐EDS. The ternary oxide coating was used for the anodic oxidation of methyl orange (MO) azo dye. Linear sweep voltammetry was used to identify the electrode potentials that favour MO degradation. Batch electrolyses were then carried out at a constant electrode potential of 1.5, 1.75 and 2.0 V vs. SHE using either a three‐electrode batch cell or a flow reactor. The dye solutions were totally decolorized via reactive oxygen species, such as ?OH, H2O2 and O3 formed in situ from water oxidation at the Ti/IrO2‐SnO2‐Sb2O5 surface. 相似文献
66.
文章采用自制催化剂A做引发剂,使引发时间从10小时10分降低到1小时25分,收率达到75%以上;同时,回收铜盐套用,大大降低了原料成本,给工业生产提供了依据. 相似文献
67.
提出用变压吸附法提纯催化裂化再生烟气或炼钢高炉尾气中的CO,通过甲醇液相氧化羰基化法生产DMC的工艺路线。这对提高企业经济效益,减轻环境污染,促进资源的合理利用,有重大而深远的意义。 相似文献
68.
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70.
结合中试工程的研究成果,评析了倒置A^2/O型一体化氧化沟工艺的特点,并探讨了在工程应用中应注意的一些问题,从投资和运行成本两个方面分析了倒置A2/O型一体化氧化沟工艺的经济性。 相似文献