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排序方式: 共有3094条查询结果,搜索用时 15 毫秒
1.
Yushu Liu Chun Gao Qing Li Prof. Dr. Huan Pang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(9):2141-2160
Nickel oxide (NiO) has emerged as one of the most promising transition-metal oxides (TMOs) for electrochemical capacitors, batteries, catalysis, and electrochromic films, owing to its cost-effectiveness, abundance, and well-defined electrochemical properties. Recent studies have identified that mixing NiO with graphene or graphene derivatives results in novel composites with synergistic effects and superior electrochemical performance. This review summarizes the latest advances in composites of NiO with graphene or graphene derivatives. The synthetic strategies, morphologies, and electrochemical performance of these composites are introduced, as well as their electrochemical applications in supercapacitors, batteries, sensors, catalysis, and so forth. Finally, tentative conclusions and assessments regarding the opportunities and challenges for the future development of these composites and other TMOs/graphene or graphene-derived composites are presented. 相似文献
2.
Bin Li Bin Wang Xiayang Huang Lu Dai Lei Cui Jian Li Xueshun Jia Chunju Li 《Angewandte Chemie (International ed. in English)》2019,58(12):3885-3889
Herein, two new classes of macrocyclic compounds, terphen[n]arenes (TPns) (n=3–6) and quaterphen[n]arenes (QPns) (n=3–6), were designed and synthesized by a one‐step condensation reaction in relatively high yields. They comprise 2,2′′‐dimethoxy terphenyl and 2,2′′′‐dimethoxy quaterphenyl monomers, respectively, linked by methylene bridges. Given their long and rigid monomers, TPns and QPns have much larger cavities and better self‐assembly properties than classic macrocycles. More interestingly, the cyclic pentamers and hexamers TP5, TP6, QP5, and QP6 formed supramolecular organogels, which were composed of interwoven fibers, nanosheets, or entangled macropore networks formed by multiple face‐to‐face and edge‐to‐face π???π stacking interactions. The xerogel materials effectively captured volatile iodine, not only in aqueous media but also in the gaseous state, and could be recycled multiple times without obvious loss in performance. 相似文献
3.
Huile Jin Jun Li James Iocozzia Xin Zeng Pai‐Chun Wei Chao Yang Nan Li Zhaoping Liu Jr Hau He Tiejun Zhu Jichang Wang Zhiqun Lin Shun Wang 《Angewandte Chemie (International ed. in English)》2019,58(43):15206-15226
Hybrid organic–inorganic materials have been considered as a new candidate in the field of thermoelectric materials since the last decade owing to their great potential to enhance the thermoelectric performance by utilizing the low thermal conductivity of organic materials and the high Seebeck coefficient, and high electrical conductivity of inorganic materials. Herein, we provide an overview of interfacial engineering in the synthesis of various organic–inorganic thermoelectric hybrid materials, along with the dimensional design for tuning their thermoelectric properties. Interfacial effects are examined in terms of nanostructures, physical properties, and chemical doping between the inorganic and organic components. Several key factors which dictate the thermoelectric efficiency and performance of various electronic devices are also discussed, such as the thermal conductivity, electric transportation, electronic band structures, and band convergence of the hybrid materials. 相似文献
4.
This study reports the structural and spectroscopic characterization of a novel metal organic compound formulated as [Fe (bpy)3] [Fe (dipic)2]2.7H2O ( 1 ) (dipic = pyridine‐2,6‐dicarboxylate and bpy = 2,2′‐bipyridine). 1 was investigated by elemental analysis, FT‐IR spectroscopy, powder X‐ray diffraction and single crystal X‐ray diffraction (SC‐XRD), which revealed a triclinic structure of expected composition. Thermal degradation of 1 was also investigated. Complex 1 was used as a precursor to prepare superparamagnetic nanoparticles of Fe3O4 by thermal analysis. The obtained Fe3O4 was characterized by Fourier transformed infrared spectroscopy (FT‐IR), powder X‐ray diffraction (XRD) and scanning electron microscopy (SEM). Fe3O4 nanoparticles were used as a nano‐adsorbent to remove Cd2+ from water at room temperature. The results showed that this nano‐adsorbent is effective in removing Cd2+ from contaminated water sources, and that the maximal effectivity of adsorption occurs at pH = 6. Magnetic measurements of complex 1 and Fe3O4 nanoparticles at room temperature revealed paramagnetic and superparamagnetic behavior, respectively. 相似文献
5.
This review examines the most recent electrochemical developments for nitrate, nitrite and ammonium detection for on-site water monitoring. There remains a high demand for effective field-based detection of the dissolved inorganic nitrogen (DIN) analytes to aid in mitigating nitrogen loading. Electrochemical approaches show increasing potential to fill this role as advancements in nanotechnology continually improve analytical performance and on-site applicability. However, translating these improvements into the field still faces the resonating challenges of reaching analytical proficiency (selectivity, sensitivity, robustness, stability), practical end-user functionality, minimal matrix interferences and cost effectiveness. Herein, we elaborate on these challenges via a critical evaluation of current studies and examine how realistic the prospects of on-site nitrate, nitrite and ammonium are. We also present recommendations in addressing these gaps to conclude the review. 相似文献
6.
Jonas H. Muessig Melanie Thaler Rian D. Dewhurst Valerie Paprocki Jens Seufert James D. Mattock Alfredo Vargas Holger Braunschweig 《Angewandte Chemie (International ed. in English)》2019,58(13):4405-4409
The lability of B=B, B?P, and B–halide bonds is combined in the syntheses of the first diiododiborenes. In a series of reactivity tests, these diiododiborenes undergo cleavage of all six of their central bonds in different ways, leading to products of B=B hydrogenation and dihalogenation as well as halide exchange. 相似文献
7.
We present novel inorganic–organic hybrid catalyst to accomplish domino multi‐component reaction (MCR) for synthesis of 3‐amino‐2′‐oxospiro[benzo[c]pyrano[3,2‐a]phenazine‐1,3′‐indoline]‐2‐carbonitrile/carboxylate derivatives. This methodology offers remarkable development by easy production of H3PMo12O40/Hyd‐SBA‐15 in regard to solving the problem of using harsh catalysts, also it demonstrates to be impressive and environmentally friendly in term of low reaction times and high yields. 相似文献
8.
蛭石对高钠高钙准东煤结渣特性影响研究 总被引:1,自引:0,他引:1
采用一维沉降炉,辅以灰熔点仪的实验方法,将蛭石与高钠高钙准东煤掺混燃烧,研究其对高钠高钙准东煤结渣特性的影响。结果表明,随着蛭石掺烧量的提高,灰熔点温度呈现先降低后升高的趋势,当掺烧量为6%时灰熔点温度最低;蛭石掺烧量越高,高钠高钙准东煤结渣情况改善越明显,当掺烧量达到4%时,渣样变得疏松多孔,质地变脆,渣样与沉积探针之间的黏附性较弱,极易通过吹灰除去,建议蛭石掺烧量为4%;煤灰中原始矿物质以石英、钙铝黄长石或钙黄长石以及辉石类的低熔点矿物质为主,掺烧蛭石后,含钠的绿辉石矿物质被转化为韭闪石,含铁的斜辉石、赤铁矿等矿物质被转化为铁橄榄石,渣样中的矿物质均以高熔点的镁橄榄石为主;蛭石具有固钠的作用,取样温度越低,蛭石掺混量越高,其固钠效果越明显。 相似文献
9.
Khaled Tawfik Alali Dr. Jingyuan Liu Dr. Rongrong Chen Dr. Qi Liu Dr. Hongsen Zhang Jundong Li Jindi Hou Prof. Rumin Li Prof. Jun Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(51):11892-11902
Semiconductor metal oxides (SMO)-based gas-sensing materials suffer from insufficient detection of a specific target gas. Reliable selectivity, high sensitivity, and rapid response–recovery times under various working conditions are the main requirements for optimal gas sensors. Chemical warfare agents (CWA) such as sarin are fatal inhibitors of acetylcholinesterase in the nerve system. So, sensing materials with high sensitivity and selectivity toward CWA are urgently needed. Herein, micro-nano octahedral Co3O4 functionalized with hexafluoroisopropanol (HFIP) were deposited on a layer of reduced graphene oxide (rGO) as a double-layer sensing materials. The Co3O4 micro-nano octahedra were synthesized by direct growth from electrospun fiber templates calcined in ambient air. The double-layer rGO/Co3O4-HFIP sensing materials presented high selectivity toward DMMP (sarin agent simulant, dimethyl methyl phosphonate) versus rGO/Co3O4 and Co3O4 sensors after the exposure to various gases owing to hydrogen bonding between the DMMP molecules and Co3O4-HFIP. The rGO/Co3O4-HFIP sensors showed high stability with a response signal around 11.8 toward 0.5 ppm DMMP at 125 °C, and more than 75 % of the initial response was maintained under a saturated humid environment (85 % relative humidity). These results prove that these double-layer inorganic–organic composite sensing materials are excellent candidates to serve as optimal gas-sensing materials. 相似文献
10.
Xiao‐Ping Zhang Yan‐Ni Li Yi‐Yang Sun Tao Zhang 《Angewandte Chemie (International ed. in English)》2019,58(51):18718-18718