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11.
Dr. Shiyong Zuo Dr. Xijun Xu Prof. Shaomin Ji Zhuosen Wang Dr. Zhengbo Liu Prof. Jun Liu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(3):830-860
As concerns about the safety of lithium-ions batteries (LIBs) increases, aqueous zinc-ion batteries (ZIBs) with a lower cost, higher safety, and higher co-efficiency have attracted more and more interest. However, finding suitable cathode materials is still an urgent problem in ZIBs. In recent years, a lot of significant works have been reported, including manganese-based cathodes, vanadium-based cathodes, Prussian blue analog-based materials, and sustainable quinone cathodes. In this review, some typical cathode materials are introduced. The detailed storage mechanisms and methods for improving the reaction kinetics of the zinc ions are summarized. Finally, the issues, challenges, and the research directions are provided. 相似文献
12.
Jazer Jose H. Togonon Eugene A. Esparcia Jr. Prof. Julie Anne D. del Rosario Prof. Joey D. Ocon 《ChemistryOpen》2021,10(4):471-476
Biodegradable primary batteries, also known as transient batteries, are essential to realize autonomous biodegradable electronic devices with high performance and advanced functionality. In this work, magnesium, copper, iron, and zinc – metals that exist as trace elements in the human body – were tested as materials for biomedical transient electronic devices. Different full cell combinations of Mg and X (where X = Cu, Fe, and Zn and the anodized form of the metals) with phosphate buffered saline (PBS) as electrolyte were studied. To form the cathodes, metal foils were anodized galvanostatically at a current density of 2.0 mA cm−2 for 30 mins. Electrochemical measurements were then conducted for each electrode combination to evaluate full cell battery performance. Results showed that the Mg−Cuanodized chemistry has the highest power density at 0.99 mW/cm2. Nominal operating voltages of 1.26 V for the first 0.50 h and 0.63 V for the next 3.7 h were observed for Mg−Cuanodized which was discharged at a current density of 0.70 mA cm−2. Among the materials tested, Mg−Cuanodized exhibited the best discharge performance with an average specific capacity of 2.94 mAh cm−2, which is comparable to previous reports on transient batteries. 相似文献
13.
Martin Sweeney Darren Conboy Styliana I. Mirallai Fawaz Aldabbagh 《Molecules (Basel, Switzerland)》2021,26(9)
This review article provides a perspective on the synthesis of alicyclic and heterocyclic ring-fused benzimidazoles, imidazo[4,5-f]benzimidazoles, and imidazo[5,4-f]benzimidazoles. These heterocycles have a plethora of biological activities with the iminoquinone and quinone derivatives displaying potent bioreductive antitumor activity. Synthesis is categorized according to the cyclization reaction and mechanisms are detailed. Nitrobenzene reduction, cyclization of aryl amidines, lactams and isothiocyanates are described. Protocols include condensation, cross-dehydrogenative coupling with transition metal catalysis, annulation onto benzimidazole, often using CuI-catalysis, and radical cyclization with homolytic aromatic substitution. Many oxidative transformations are under metal-free conditions, including using thermal, photochemical, and electrochemical methods. Syntheses of diazole analogues of mitomycin C derivatives are described. Traditional oxidations of o-(cycloamino)anilines using peroxides in acid via the t-amino effect remain popular. 相似文献
14.
15.
Modified High‐Nickel Cathodes with Stable Surface Chemistry Against Ambient Air for Lithium‐Ion Batteries 下载免费PDF全文
Dr. Ya You Dr. Hugo Celio Jianyu Li Dr. Andrei Dolocan Prof. Dr. Arumugam Manthiram 《Angewandte Chemie (International ed. in English)》2018,57(22):6480-6485
High‐Ni layered oxides are promising next‐generation cathodes for lithium‐ion batteries owing to their high capacity and lower cost. However, as the Ni content increases over 70 %, they have a high dynamic affinity towards moisture and CO2 in ambient air, primarily reacting to form LiOH, Li2CO3, and LiHCO3 on the surface, which is commonly termed “residual lithium”. Air exposure occurs after synthesis as it is common practice to handle and store them under ambient conditions. The air exposure leads to significant performance losses, and hampers the electrode fabrication, impeding their practical viability. Herein, we show that substituting a small amount of Al for Ni in the crystal lattice notably improves the chemical stability against air by limiting the formation of LiOH, Li2CO3, LiHCO3, and NiO in the near‐surface region. The Al‐doped high‐Ni oxides display a high capacity retention with excellent rate capability and cycling stability after being exposed to air for 30 days. 相似文献
16.
V. B. Vol'eva T. I. Prokofeva A. I. Prokofev I. S. Belostotskaya N. L. Komissarova V. V. Ershov 《Russian Chemical Bulletin》1995,44(9):1720-1724
The interaction of 3,6-di-tert-butyl-ortho-benzoquinone (1) and 3,5-di-tert-butyl-ortho-benzoquinone (2) with NH3 in water—alcohol medium and with (NH4)2CO3 in a solid phase has been studied. Redox processes with participation of a nucleophile of the medium take place for1, while2 reacts with NH3 at the carbonyl group with transformation of the quinone imide. The mechanism of redox transformation of1 has been proposed.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1789–1793, September, 1995.This work was carried out with financial support from the Russian Foundation for Basic Research (Project No. 94-03-08653). 相似文献
17.
Dr. Sheng Cao Robin Christiansen Prof. Xiaohua Peng 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(27):9050-9058
A series of arylboronic esters containing different aromatic substituents and various benzylic leaving groups (Br or N+Me3Br?) have been synthesized. The substituent effects on their reactivity with H2O2 and formation of quinone methide (QM) have been investigated. NMR spectroscopy and ethyl vinyl ether (EVE) trapping experiments were used to determine the reaction mechanism and QM formation, respectively. QMs were not generated during oxidative cleavage of the boronic esters but by subsequent transformation of the phenol products under physiological conditions. The oxidative deboronation is facilitated by electron‐withdrawing substituents, such as aromatic F, NO2, or benzylic N+Me3Br?, whereas electron‐donating substituents or a better leaving group favor QM generation. Compounds containing an aromatic CH3 or OMe group, or a good leaving group (Br), efficiently generate QMs under physiological conditions. Finally, a quantitative relationship between the structure and activity has been established for the arylboronic esters by using a Hammett plot. The reactivity of the arylboronic acids/esters and the inhibition or facilitation of QM formation can now be predictably adjusted. This adjustment is important as some applications may benefit and others may be limited by QM generation. 相似文献
18.
《Angewandte Chemie (International ed. in English)》2017,56(40):12064-12084
Magnesium metal is a superior anode which has double the volumetric capacity of lithium metal and has a negative reduction potential of −2.37 V vs. the standard hydrogen electrode. A major benefit of magnesium is the apparent lack of dendrite formation during charging which is one of the crucial concerns of using a lithium metal anode. In this Review, we highlight the foremost research in the development of electrolytes and cathodes and discuss some of the significant challenges which must be overcome in realizing a practical magnesium battery. 相似文献
19.
本文对几种人工光合作用反应中心系统,做一个简单的综述,其中包括叶绿素和细菌叶绿素二聚体,卟啉二聚体,卟啉-苯醌共价键络合物以及其他合成中心。 相似文献
20.
Selectivity in the Aerobic Dearomatization of Phenols: Total Synthesis of Dehydronornuciferine by Chemo‐ and Regioselective Oxidation 下载免费PDF全文
Kenneth Virgel N. Esguerra Prof. Dr. Jean‐Philip Lumb 《Angewandte Chemie (International ed. in English)》2018,57(6):1514-1518
We describe a selective aerobic oxidation of meta‐biaryl phenols that enables rapid access to functionalized phenanthrenes. Aerobic oxidations attract interest due to their efficiency, but remain underutilized in complex molecule settings due to challenges of selectivity. We discuss these issues in the context of Cu catalysis, and highlight the advantages of confining oxygen activation and substrate oxidation to the catalyst's inner‐coordination sphere. This gives rise to predictable selectivity that we use for a concise synthesis of the aporphine dehydronornuciferine. 相似文献