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《International Journal of Hydrogen Energy》2022,47(71):30494-30502
Metal-organic frameworks (MOFs) have emerged as efficient electrocatalysts due to the features of high specific surface area, rich pore structure and diversified composition. It is still challenging to synthesize self-supporting MOF-based catalysts using simple and low-cost fabrication methods. Herein, we successfully fabricated Ni-doped MIL-53(Fe) supported on nickel-iron foam (Ni-MIL-53(Fe)/NFF) as efficient electrocatalyst. A facile two-step solvothermal method without adding any metal salts was used, which can simplify the fabrication process and reduce the experimental cost. In the fabrication process, the bimetallic Ni-MIL-53(Fe)/NFF was in situ converted from an intermediate NiFe2O4/NFF. The obtained material exhibits outstanding electrocatalytic oxygen evolution performance with a low overpotential of 248 mV at 50 mA cm?2, and a small Tafel slope of 46.4 mV dec?1. This work sheds light on the simple and efficient preparation of bimetallic MOF-based material, which is promising in electrocatalysts. 相似文献
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《International Journal of Hydrogen Energy》2022,47(69):29685-29697
Electrocatalytic water splitting is an important method to produce green and renewable hydrogen (H2). One of the hindrances for wide applications of electrocatalysis in H2 production is the lack of freshwater resources. Comparatively, seawater splitting has become an effective approach for large-scale H2 production due to its abundant reserves. However, the increased complexity of seawater content emerged more problems in electrocatalytic seawater splitting. Recently, various strategies have been reported on improving the performance of electrocatalysts applied in seawater. Herein, this review firstly analyzed the mechanisms and challenges of electrocatalytic seawater splitting to evolve H2, and summarized the recent progress on H2 production in electrocatalytic seawater splitting. Furthermore, suggestions for future work have been provided for guidance. 相似文献
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《Ceramics International》2022,48(7):9651-9657
Friction is a common clean energy and can be harvested and converted into electricity energy via triboelectricity, which can electrochemically drive dye decomposition in theory. In this work, the tribocatalytic Rhodamine B dye decomposition has been experimentally realized in strontium titanate (SrTiO3) nanofibers, which are synthesized via a hydrothermal method. In the tribocatalytic dye decomposition process, the friction is exerted in the interface between catalyst surface and a polytetrafluoroethylene (PTFE) Teflon rod setup with the different stirring speed. The RhB dye decomposition ratios of SrTiO3 nanofibers at these stirring speeds of 200 rpm, 400 rpm, 600 rpm, and 800 rpm are respectively 24.2%, 51.8%, 73.9% and 88.6%, yielding to these reaction rate constants of ~0.0112 h?1, ~0.0260 h?1, ~0.0562 h?1 and ~0.0877 h?1. The main active species, which play an important role in tribocatalytic process, are the superoxide radicals and holes on basis of the active species quenching experiment results. The excellent tribocatalysis activity makes SrTiO3 nanofibers potential for application in dye wastewater treatment through utilizing the environmental friction energy. 相似文献
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合金元素对铝合金在泰国曼谷地区初期腐蚀行为的影响 总被引:1,自引:0,他引:1
在泰国曼谷地区对5083、6063和7020 3种铝合金进行为期1 a的暴晒实验,采用SEM、电化学实验、XPS和扫描Kelvin探针显微镜(SKPFM)对3种铝合金初期腐蚀形貌及腐蚀机理进行研究。结果表明:6063铝合金中Mg、Si、Fe等合金元素含量较少,腐蚀电位相对较高,约为-0.66 V (vs SCE),腐蚀产物膜较为致密,耐蚀性较好,在泰国曼谷地区的腐蚀速率约为0.7 g/(m^2·a)。7020铝合金含有较多Mg、Zn等合金元素,腐蚀电位约为-0.78 V (vs SCE),腐蚀最为严重,腐蚀速率约为3.26 g/(m^2·a)。3种铝合金均含有Mn、Si、Fe等合金元素,从而形成Fe-Si-Al或Fe-Si(Mn)-Al第二相,第二相表面电位高于基体225~280 mV,在大气环境中第二相作为阴极相,周围的基体Al优先溶解脱落,成为点蚀坑。 相似文献
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《International Journal of Hydrogen Energy》2020,45(38):19601-19610
Solid polymer electrolytes provide high safety and good electrochemical stability in solid-state lithium batteries (SSLBs) compared with conventional liquid electrolytes. In this work, a novel solid polymer composite electrolyte based on poly (ethylene oxide) (PEO) filled with rod-like Zn2(OH)BO3 particles was prepared by a grinding process followed with a heating treatment process and a cold pressing process. The effect of the incorporation amount of rod-like Zn2(OH)BO3 particles on the ionic conductivity was investigated systemically. It is found that 10 mol% of rod-like Zn2(OH)BO3 particles addition resulted in a highest ionic conductivity of 2.78 × 10−5 at 30 °C and the improved ionic conductivity was considered to be caused by the reducing of PEO crystallinity and the increasing of Li ion migrating pathway on the interface between the Zn2(OH)BO3 and PEO. In addition, the optimum composite electrolyte exhibited a high electrochemical stability window of 4.51 V (vs. Li/Li+), good lithium stability and excellent thermal stability. 相似文献
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丙烯醇是一种十分重要的中间体和化学原料。近年来,以甘油为原料直接制备丙烯醇的研究引起了许多科学家的关注。本文参考了最近十年来发表的文献,详细介绍了均相甲酸诱导的甘油脱氧脱水反应、催化剂作用下的甘油脱氧脱水反应、液固相甘油氢解反应和气固相甘油氢转移反应等过程制备丙烯醇的相关工艺、反应机理和催化剂的研究进展及发展趋势,并对比了上述工艺的优缺点。其中,均相甲酸诱导的甘油脱氧脱水工艺比较成熟,已经在实验室中得到验证和应用,但是甲酸的消耗量大,整个过程的原子经济性很差。 甘油脱氧脱水反应和液固相甘油氢解反应不仅需要采用价格昂贵的铼基催化剂,而且丙烯醇的选择性较低。 铁基催化剂作用下的气固相甘油氢转移反应制备丙烯醇,由于催化剂的价格低廉、制备工艺简单、产品分离容易等优势而备受关注,是最近五年的研究热点。在文献基础上,认为今后研究应该重点关注催化剂的酸碱性、氢转移能力及其与速率控制步骤的匹配,并有针对性地对催化剂进行优化和改进。 相似文献
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