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11.
Rechargeable aqueous zinc batteries (RAZB) have been re-evaluated because of the superiority in addressing safety and cost concerns. Nonetheless, the limited lifespan arising from dendritic electrodeposition of metallic Zn hinders their further development. Herein, a metal–organic framework (MOF) was constructed as front surface layer to maintain a super-saturated electrolyte layer on the Zn anode. Raman spectroscopy indicated that the highly coordinated ion complexes migrating through the MOF channels were different from the solvation structure in bulk electrolyte. Benefiting from the unique super-saturated front surface, symmetric Zn cells survived up to 3000 hours at 0.5 mA cm−2, near 55-times that of bare Zn anodes. Moreover, aqueous MnO2–Zn batteries delivered a reversible capacity of 180.3 mAh g−1 and maintained a high capacity retention of 88.9 % after 600 cycles with MnO2 mass loading up to 4.2 mg cm−2.  相似文献   
12.
Integration of MnOx into the carbon matrix proves a viable strategy to improve the electrochemical performance of MnOx materials. Mn3O4 nanoparticle-decorated N-doped carbon composites (Mn3O4@N-doped carbon) were facilely prepared from a non-porous eight-fold interpenetrated ZnII-based MOF, which involves first synthesis of bimetallic Mn/Zn-MOF in one-pot reaction followed by direct pyrolysis at 1000 °C. In 0.1 m KOH solution, the optimal Mn3O4@N-doped carbon exhibits decent oxygen reduction activity with the onset potential (Eonset) of 0.94 V (vs. RHE) and half-wave potential (E1/2) of 0.81 V (vs. RHE), excellent methanol tolerance as well as good durability.  相似文献   
13.
Metal–organic frameworks (MOFs) with long-term stability and reversible high water uptake properties can be ideal candidates for water harvesting and indoor humidity control. Now, a mesoporous and highly stable MOF, BIT-66 is presented that has indoor humidity control capability and a photocatalytic bacteriostatic effect. BIT-66 (V3(O)3(H2O)(BTB)2), possesses prominent moisture tunability in the range of 45–60 % RH and a water uptake and working capacity of 71 and 55 wt %, respectively, showing good recyclability and excellent performance in water adsorption–desorption cycles. Importantly, this MOF demonstrates a unique photocatalytic bacteriostatic behavior under visible light, which can effectively ameliorate the bacteria and/or mold breeding problem in water adsorbing materials.  相似文献   
14.
Antiperovskite Co3InC0.7N0.3 nanomaterials with highly enhanced oxygen reduction reaction (ORR) performance were prepared by tuning nitrogen contents through a metal–organic framework (MOF)‐derived strategy. The nanomaterial surpasses all reported noble‐metal‐free antiperovskites and even most perovskites in terms of onset potential (0.957 V at J=0.1 mA cm?2) and half‐wave potential (0.854 V). The OER and zinc–air battery performance demonstrate its multifunctional oxygen catalytic activities. DFT calculation was performed and for the first time, a 4 e? dissociative ORR pathway on (200) facets of antiperovskite was revealed. Free energy studies showed that nitrogen substitution could strengthen the OH desorption as well as hydrogenation that accounts for the enhanced ORR performance. This work expands the scope for material design via tailoring the nitrogen contents for optimal reaction free energy and hence performance of the antiperovskite system.  相似文献   
15.
We report the synthesis of a set of 2D metal–organic frameworks (MOFs) constructed with organosilicon‐based linkers. These oligosilyl MOFs feature linear SinMe2n(C6H4CO2H)2 ligands (lin‐Sin, n=2, 4) connected by Cu paddlewheels. The stacking arrangement of the 2D sheets is dictated by van der Waals interactions and is tunable by solvent exchange, leading to reversible structural transformations between many crystalline and amorphous phases.  相似文献   
16.
Rational engineering and assimilation of diverse chemo‐ and biocatalytic functionalities in a single nanostructure is highly desired for efficient multistep chemical reactions but has so far remained elusive. Here, we design and synthesize multimodal catalytic nanoreactors (MCNRs) based on a mesoporous metal‐organic framework (MOF). The MCNRs consist of customizable metal nanocrystals and stably anchored enzymes in the mesopores, as well as coordinatively unsaturated cationic metal MOF nodes, all within a single nanoreactor space. The highly intimate and diverse catalytic mesoporous microenvironments and facile accessibility to the active site in the MCNR enables the cooperative and synergistic participation from different chemo‐ and biocatalytic components. This was shown by one‐pot multistep cascade reactions involving a heterogeneous catalytic nitroaldol reaction followed by a [Pd/lipase]‐catalyzed chemoenzymatic dynamic kinetic resolution to yield optically pure (>99 % ee) nitroalcohol derivatives in quantitative yields.  相似文献   
17.
Metal–organic frameworks (MOFs) with long‐term stability and reversible high water uptake properties can be ideal candidates for water harvesting and indoor humidity control. Now, a mesoporous and highly stable MOF, BIT‐66 is presented that has indoor humidity control capability and a photocatalytic bacteriostatic effect. BIT‐66 (V3(O)3(H2O)(BTB)2), possesses prominent moisture tunability in the range of 45–60 % RH and a water uptake and working capacity of 71 and 55 wt %, respectively, showing good recyclability and excellent performance in water adsorption–desorption cycles. Importantly, this MOF demonstrates a unique photocatalytic bacteriostatic behavior under visible light, which can effectively ameliorate the bacteria and/or mold breeding problem in water adsorbing materials.  相似文献   
18.
采用基于单轴各向异性完美匹配层吸收边界的频域有限差分方法研究一种椭圆芯高双折射微结构光纤的特性.通过计算,分析了空气孔尺寸和孔距对模式双折射、泄漏损耗以及模式截止波长的影响;综合研究了双折射微结构光纤的几种特性及其相互之间的影响和制约关系;并首次采用有效面积的方法研究高双折射微结构光纤的模式截止特性,分析单模传输条件;从而为高双折射微结构光纤的设计提供了一定的理论依据.  相似文献   
19.
汪鹏飞  汪丽君 《无机化学学报》2018,34(12):2254-2260
通过一个含3个羧基基团的多功能配体2-羟基-1,3,5-苯基三羧酸(HO-H3BTC)与锌盐构筑了一个三维多孔锌骨架结构配合物,{[Zn4(O-BTC)2(H2O)5]·2DMF·0.5H2O}n1)。通过单晶X射线衍射、粉末X射线衍射、元素分析、红外光谱、热重分析以及固体紫外吸收光谱对该配合物进行了表征。配合物1是通过棒状金属锌-羧酸/羟基次级结构单元构筑的一个三维骨架结构,其在室温下显示强烈的蓝色荧光。此外,在低温条件下(10 K)配合物1显示余晖性质。  相似文献   
20.
金属有机框架材料的研究进展   总被引:1,自引:0,他引:1  
金属有机框架(metal-organic frameworks,MOFs)材料是一类由有机配体与金属中心经过自组装形成的具有可调节孔径的材料。与传统无机多孔材料相比,MOFs材料具有更大的比表面积,更高的孔隙率,结构及功能更加多样,因而已经被广泛应用于气体吸附与分离、传感器、药物缓释、催化反应等领域中。新兴材料的出现极大地促进了各个学科间的相互发展,本文综述了近年来MOFs材料的研究发展,包括MOFs材料自身的特点、国内外发展现状、应用领域以及复合MOFs材料的研究热点,并对今后的发展进行了展望。  相似文献   
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