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1.
《Mendeleev Communications》2022,32(2):226-227
We report a nickel tetrathiooxalate (NiTTO) coordination polymer as a cathode material for potassium batteries. In a potential range of 1.3–3.6 V vs. K+/K, the specific capacity of the material is 209 mA h g?1 at a current density of 0.1 A g?1, which roughly corresponds to the two-electron reduction of polymer repeating units. The charge–discharge mechanisms of NiTTO in potassium cells were examined using operando Raman spectroscopy.  相似文献   
2.
Metal-sulfur batteries are a promising next-generation energy storage technology, offering high theoretical energy densities with low cost and good sustainability. An active area of research is the development of electrolytes that address unwanted migration of sulfur and intermediate species known as polysulfides during operation of metal-sulfur batteries, a phenomenon that leads to low energy efficiency and short life-spans. A particular class of electrolytes, gel polymer electrolytes, are especially attractive for their ability to repel polysulfides on the basis of structure, electrostatics, and other polymer properties. Herein, within the context of magnesium- and lithium-sulfur batteries, we investigate the impact of gel polymer electrolyte cation solvation capacity, a property related to network dielectric constant and chemistry, on sulfur/polysulfide-polymer interactions, an understudied property-performance relationship. Polymers with lower cation solvation capacity are found to permanently absorb less polysulfide active material, which increases sulfur utilization for Li−S batteries and significantly increases charge efficiency and life-span for Li−S and Mg−S batteries.  相似文献   
3.
Yuejun Ding 《中国物理 B》2022,31(6):68201-068201
Na-ion batteries (NIBs) are regarding as the optimum complement for Li-ion batteries along with the rapid development of stationary energy storage systems. In order to meet the commercial demands of cathodes for NIBs, O3-type Cu containing layered oxide Na0.90Cu0.22Fe0.30Mn0.48O2 with good comprehensive performance and low-cost element components is very promising for the practical use. However, only part of the Cu3+/Cu2+ redox couple participated in the redox reaction, thus impairing the specific capacity of the cathode materials. Herein, Mg2+-doped O3-Na0.90Mg0.08Cu0.22Fe0.30Mn0.40O2 layered oxide without Mn3+ was synthesized successfully, which exhibited improved reversible specific capacity of 118 mAh/g in the voltage range of 2.4-4.0 V at 0.2 C, corresponding to the intercalation/deintercalation of 0.47 Na+ (0.1 more than that of Na0.90Cu0.22Fe0.30Mn0.48O2). This work demonstrates an important strategy to obtain advanced layered oxide cathodes for NIBs.  相似文献   
4.
双金属有机骨架及其衍生物一方面具有单金属有机骨架孔道丰富、比表面积大、结构可调、活性位点丰富等特点,另一方面具有双组分与多孔结构之间的协同效应,因而受到了研究人员的密切关注,在储能、催化、分离、传感器、医药、气体存储等领域广泛应用。和单金属MOFs类似,双金属MOFs的导电性不佳、结构易坍塌,这极大地限制了其在电化学储能中的应用。通过对双金属MOFs进行热处理,易得到分布均匀的多孔碳@双金属氧化物/硫化物/磷化物/硒化物等衍生物,不仅保持了独特的多孔结构,而且提高了材料的导电性和结构稳定性,有利于在电化学储能中的应用。因此,本文从双金属MOFs中的主要金属离子入手,综述了双金属MOFs及其衍生物用于超级电容器、锂离子电池、钠离子电池、金属空气电池等电化学储能器件的最新应用进展。在此基础上,总结了双金属MOFs在电化学储能应用中的优势,并对其制备、作用机理和后处理研究提出了建议。  相似文献   
5.
Thiacalixarene-supported Co32nanoclusters encapsulated in polyacrylonitrile nanofibers(Co32@PAN-NFs) by electrospinning have been utilized as precursors to fabricate N-doped CoO@Co9S8 carbon nanofibers(CoO@Co9S8@CNFs) for superior Li-ion storage. The S-rich Co32 clusters capped by organic sheets afforded the well dispersed cobalt oxide/sulfide nanoparticles embedded in carbon nanofiber composites by direct calcination. The N-doped CoO@Co9S8@CNFs nanocomposites have been utilized as anode materials for lithium ion battery with the reversible capabilities being of 1051.8, 967.6, 894.7, 782.7, 669.5 and 525.4 mA·h/g at 0.1, 0.2, 0.5, 1, 2 and 3 A/g, respectively. The CoO@Co9S8@CNFs also showed a relatively high stable capacity of 551.7 mA·h/g at the current density of 1 A/g after 200 cycles of rate experiments. The as-obtained N-doped CoO@Co9S8@CNFs nanocomposites exhibited superior reversible capacity, rate performance, Coulomb efficiency(74.5% vs. 63.9%) and cyclic stability comparing with the CoO@Co9S8@C derived from simple annealing of Co32 templates.  相似文献   
6.
The carbon composite materials have been a research hotspot in the fields of catalysis, energy conversion and so on, because of their features of large structure and morphology variety, good chemical and electrochemical stability, and high electronic conductivity, large specific surface area and rich active sites. This paper summarizes some research progress of carbon composite materials, including assembly methodologies, their structure regulation, properties, and related applications. Moreover, the current challenges and the prospects of these materials are also discussed.  相似文献   
7.
Controlling redox activity of judiciously appended redox units on a photo-sensitive molecular core is an effective strategy for visible light energy harvesting and storage. The first example of a photosensitizer - electron donor coordination compound in which the photoinduced electron transfer step is used for light to electrical energy conversion and storage is reported. A photo-responsive Ru-diimine module conjugated with redox-active catechol groups in [Ru(II)(phenanthroline-5,6-diolate)3]4− photosensitizer can mediate photoinduced catechol to dione oxidation in the presence of a sacrificial electron acceptor or at the surface of an electrode. Under potentiostatic condition, visible light triggered current density enhancement confirmed the light harvesting ability of this photosensitizer. Upon implementation in galvanostatic charge-discharge of a Li battery configuration, the storage capacity was found to be increased by 100 %, under 470 nm illumination with output power of 4.0 mW/cm−2. This proof-of-concept molecular system marks an important milestone towards a new generation of molecular photo-rechargeable materials.  相似文献   
8.
A mathematical model of simultaneous cobalt deposition and hydrogen evolution was developed and applied to the electroreduction process of 5 mM Co2+ ions investigated by cyclic voltammetry (CV) technique at different hydrogen ion concentrations (pH=2, 3, 4). The kinetic parameters of such a complex process were determined, and the validity of the model and its sensitivity to changes in individual parameters were verified. The relative value of the approximate standard deviation (ASD%) was used to determine the degree of fit of the model to the experimental data. The catalytic effect of cobalt on the hydrogen evolution process was comprehensively confirmed.  相似文献   
9.
徐涵  潘兆瑞  亓昭鹏  孙洁 《无机化学学报》2022,38(12):2479-2490
在溶剂热条件下,合成了3个基于V型配体的Zn(Ⅱ)金属有机骨架:{[Zn2(BIDPS)2(OBA)2]·DMA}n(1)、{[Zn (BIDPT)(PA)]·DMF}n(2)和{[Zn (BIDPS)(PA)(H2O)2]·2H2O}n(3)(BIDPS=4,4''-二(1-咪唑基)苯砜,H2OBA=4,4''-二苯醚二甲酸,H2PA=帕莫酸,BIDPT=4,4''-二(1-咪唑基)苯硫醚)。利用X射线单晶衍射、红外光谱、元素分析、热重分析、X射线粉末衍射对其结构进行了表征。配合物1具有二重穿插的三维cds拓扑网络结构。配合物2为二维(4,4)层状结构,层与层之间通过互锁形成2D→3D的三维金属有机骨架。配合物3具有一维链状结构,一维链通过分子内和分子间氢键连接,形成三维超分子结构。荧光研究表明,配合物1~3可以在pH=4~10的水溶液中稳定存在,且在水中具有较强的发光性能,可作为检测2,4,6-三硝基苯酚和Fe3+的发光传感器,具有较高的灵敏度和选择性。  相似文献   
10.
祁育  章福祥 《化学学报》2022,80(6):827-838
利用太阳能光催化分解水制氢是解决能源环境问题并实现太阳能有效转化和储存最有前途的技术之一, 这一“圣杯”式反应经过几十年不懈努力取得了诸多重要研究进展. 本文将综述光催化分解水制氢体系的基本概念、活性测试方法与注意事项、光催化材料种类等; 并从光催化分解水制氢的光吸收、光生电荷分离和表面催化反应等基本过程和关键科学问题的角度总结其重要研究进展, 最后对于太阳能光催化分解水制氢的挑战和潜在的发展方向进行分析和展望. 希望通过本综述的简要介绍能让刚从事光催化分解水制氢研究的青年科技人员清晰地了解掌握该领域的一些基本概念、操作规范、研究总体进展和现状等.  相似文献   
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