A photoelectrochemical method for the C−H alkylation of heteroarenes with organotrifluoroborates has been developed. The merger of electrocatalysis and photoredox catalysis provides a chemical ...oxidant‐free approach for the generation and functionalization of alkyl radicals from organotrifluoroborates. A variety of heteroarenes were functionalized using primary, secondary, and tertiary alkyltrifluoroborates with excellent regio‐ and chemoselectivity.
A radical approach: A photoelectrochemical method has been developed for the C−H alkylation of heteroarenes with organotrifluoroborates under oxidant‐free conditions. A variety of heteroarenes can be functionalized with primary, secondary, and tertiary alkyl groups with excellent regio‐ and chemoselectivity.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Developing high‐performance batteries through applying renewable resources is of great significance for meeting ever‐growing energy demands and sustainability requirements. Biomaterials have ...overwhelming advantages in material abundance, environmental benignity, low cost, and more importantly, multifunctionalities from structural and compositional diversity. Therefore, significant and fruitful research on exploiting various natural biomaterials (e.g., soy protein, chitosan, cellulose, fungus, etc.) for boosting high‐energy lithium‐based batteries by means of making or modifying critical battery components (e.g., electrode, electrolyte, and separator) are reported. In this review, the recent advances and main strategies for adopting biomaterials in electrode, electrolyte, and separator engineering for high‐energy lithium‐based batteries are comprehensively summarized. The contributions of biomaterials to stabilizing electrodes, capturing electrochemical intermediates, and protecting lithium metal anodes/enhancing battery safety are specifically emphasized. Furthermore, advantages and challenges of various strategies for fabricating battery materials via biomaterials are described. Finally, future perspectives and possible solutions for further development of biomaterials for high‐energy lithium‐based batteries are proposed.
Adopting biomaterials for boosting high‐energy lithium‐based batteries strongly benefits sustainable and clean energy storage. This review covers primary strategies for engineering of electrodes, electrolytes, and separators by biomaterials, which aim to resolve the critical issues of high‐energy lithium‐based batteries. Significant contributions from biomaterials to specific battery systems, current challenges for each strategy, and forthcoming opportunities are discussed.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The charge transport system in an energy storage device (ESD) fundamentally controls the electrochemical performance and device safety. As the skeleton of the charge transport system, the “traffic” ...networks connecting the active materials are primary structural factors controlling the transport of ions/electrons. However, with the development of ESDs, it becomes very critical but challenging to build traffic networks with rational structures and mechanical robustness, which can support high energy density, fast charging and discharging capability, cycle stability, safety, and even device flexibility. This is especially true for ESDs with high‐capacity active materials (e.g., sulfur and silicon), which show notable volume change during cycling. Therefore, there is an urgent need for cost‐effective strategies to realize robust transport networks, and an in‐depth understanding of the roles of their structures and properties in device performance. To address this urgent need, the primary strategies reported recently are summarized here into three categories according to their controllability over ion‐transport networks, electron‐transport networks, or both of them. More specifically, the significant studies on active materials, binders, electrode designs based on various templates, pore additives, etc., are introduced accordingly. Finally, significant challenges and opportunities for building robust charge transport system in next‐generation energy storage devices are discussed.
The charge‐transport network structures serving as conduction pathways for ions/electrons play an increasingly critical role in next‐generation energy‐storage devices. They fundamentally control the overall electrochemical performance, device safety, and flexibility. The tremendous efforts on composite electrodes, from the perspective of transport network structures, are summarized and discussed.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Indoles and azaindoles are among the most important heterocycles because of their prevalence in nature and their broad utility in pharmaceutical industry. Reported herein is an unprecedented ...noble‐metal‐ and oxidant‐free electrochemical method for the coupling of (hetero)arylamines with tethered alkynes to synthesize highly functionalized indoles, as well as the more challenging azaindoles.
It's electric: An electrochemical coupling of (hetero)arylamines with tethered alkynes has been developed and provides highly chemo‐ and regioselective access to densely functionalized indoles and azaindoles. The electrochemical reaction employs ferrocene (Cp2Fe), an inexpensive organometallic reagent, as the redox catalyst and produces H2 as the only theoretical byproduct.
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Within decades of development, carbon nanomaterials such as carbon black, fullerene, carbon nanotube, carbon nanofiber, graphene and their combined nanofillers have been tremendously applied in ...polymer material industries, generating a series of fascinating multifunctional composites in the fields from portable electronic devices, sports, entertainments to automobile, aerospace and military. Among the various material properties of the composites, electrical conductivity and mechanical performance are the two most important parameters for evaluating the effectiveness of nanofillers in the polymer matrices. In this review, we focus on the electrical and mechanical properties of diverse dimensional carbon nanofillers (e.g., zero-, one-, two-, three-dimensional nanofillers or their combinations)-reinforced polymer composites to seek the most efficient and effective approach to obtain high-performance polymeric nanocomposites.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Due to the large volume change of sulfur and the diffusion of dissolved polysulfides, the development of a high-performance binder with functionality beyond mechanical adhesion/support for sulfur ...cathodes is in high demand. This is especially true for the success of high-loading sulfur cathodes. Here, we report a soy-protein-based binder with high mechanical robustness and multiple functionality for high-energy lithium–sulfur batteries. The multi-functional binder (denoted as SP-PAA) is fabricated via facilely incorporating soy protein (SP) with poly(acrylic acid) (PAA) and it has been demonstrated to effectively buffer the large volume change of the sulfur cathode during cycling. More significantly, the abundant polar groups ( e.g. amines, carboxyl groups, etc. ) of soy protein empower the binder with a strong capability to adsorb polysulfides, as evidenced by density functional theory (DFT) calculations. Meanwhile, the good ion-conduction abilities of soy protein notably promote electrochemical reactions. With the use of this binder, the electrochemical performance ( e.g. capacity, cycling stability and rate capability) of the sulfur cathode is substantially enhanced. In addition, owing to the excellent mechanical properties of SP-PAA and its effects on improving electrode microstructures, high-loading sulfur cathodes (>5 mg cm −2 ) with good and stable performance are achieved. The good performance is also attributed to the role that SP-PAA plays in adsorbing polysulfides, sustaining structural stability and promoting electrochemical reactions. This study brings about a cost-effective strategy for the fabrication of superior binders through exploiting natural materials and leads to the realization of high-loading sulfur cathodes for mass production.
C−H/N‐H cross‐coupling is an ideal strategy to synthesize various amines but remains challenging owing to the requirement for sacrificial chemical oxidants and the difficulty in controlling the ...regio‐ and chemo‐selectivity. Herein we report a site‐selective electrochemical amination reaction that can convert benzylic C−H bonds into C‐N linkages via H2 evolution without need for external oxidants or metal catalysts. The synthetic strategy involves anodic cleavage of benzylic C−H to form a carbocation intermediate, which is then trapped with an amine nucleophile leading to C−N bond formation. Key to the success is to include HFIP as a co‐solvent to modulate the oxidation potentials of the alkylbenzene substrate and the aminated product to avoid overoxidation of the latter.
An electrooxidative C−H/N−H cross‐coupling reaction with excellent site selectivity for benzylic positions is presented. The electrochemical C−H amination reaction employs easily available starting materials and proceeds under mild conditions without need for transition‐metal catalysts and external chemical oxidants.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The innovation on the low dimensional nanomaterials brings the rapid growth of nano community. Developing the controllable production and commercial applications of nanomaterials for sustainable ...society is highly concerned. Herein, carbon nanotubes (CNTs) with sp2 carbon bonding, excellent mechanical, electrical, thermal, as well as transport properties are selected as model nanomaterials to demonstrate the road of nanomaterials towards industry. The engineering principles of the mass production and recent progress in the area of CNT purification and dispersion are described, as well as its bulk application for nanocomposites and energy storage. The environmental, health, and safety considerations of CNTs, and recent progress in CNT commercialization are also included. With the effort from the CNT industry during the past 10 years, the price of multi‐walled CNTs have decreased from 45 000 to 100 $ kg−1 and the productivity increased to several hundred tons per year for commercial applications in Li ion battery and nanocomposites. When the prices of CNTs decrease to 10 $ kg−1, their applications as composites and conductive fillers at a million ton scale can be anticipated, replacing conventional carbon black fillers. Compared with traditional bulk chemicals, the controllable synthesis and applicationsof CNTs on a million ton scale are still far from being achieved due to the challenges in production, purification, dispersion, and commercial application. The basic knowledge of growth mechanisms, efficient and controllable routes for CNT production, the environmental and safety issues, and the commercialization models are still inadequate. The gap between the basic scientific research and industrial development should be bridged by multidisciplinary research for the rapid growth of CNT nano‐industry.
The mass production engineering principles and advances in carbon nanotube (CNT) purification, dispersion, as well as bulk applications for nanocomposite and energy storage are reviewed. The environmental, health, and safety considerations of CNTs, and the recent progress on CNT commercialization are also included. The gap between the basic scientific research and industrial development should be bridged by multidisciplinary research for the rapid growth of CNT nano‐industry.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Lithium (Li) dendrites in Li anodes, and dissolution and migration of manganese (Mn) ions in LiMn2O4 (LMO) cathodes, have hampered these extraordinary electrode materials from being efficiently ...applied in high performance Li batteries. Here, a novel, bifunctional, biobased composite gel polymer electrolyte (c‐GPE) is created to simultaneously deal with the two critical issues. The skeleton of c‐GPE is constructed from a sandwich structure composed of porous polydopamine spheres and two layers of the environmentally friendly soy protein isolate‐based nanofiber membranes, and the carbonized polydopamine spheres are coated without any binder on the surface of the membranes. After a facile and innocuous preparation process, the skeleton material displays excellent thermal stability and good affinity to liquid electrolyte, which endows c‐GPE with significant functions of effective mitigation of the dissolution of Mn ions, and chelation of the fleeing Mn ions, as well as the dramatic suppression of Li dendrite growth. Consequently, the LMO/Li batteries involving c‐GPE show a great improvement in the cycling stability and rate performance compared with those of the cells based on commercial Celgard 2400. This work will be quite promising to meet the distinct requirements from Li batteries and provide a high‐efficiency and safe biobased GPE for next generation energy storage systems.
A biobased composite gel polymer electrolyte (c‐GPE) is designed and successfully fabricated for suppressing lithium dendrites and tramping manganese ions simultaneously. The skeleton of the c‐GPE consists of a layer of mesoporous polydopamine spheres, two layers of soy protein‐based nanofiber membranes, and a layer of mesoporous carbonized polydopamine spheres.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Chlorine disinfection to drinking water plays an important role in preventing and controlling waterborne disease outbreaks globally. Nevertheless, little is known about why it enriches the antibiotic ...resistance genes (ARGs) in bacteria after chlorination. Here, ARGs released from killed antibiotic-resistant bacteria (ARB), and culturable chlorine-injured bacteria produced in the chlorination process as the recipient, were investigated to determine their contribution to the horizontal transfer of ARGs during disinfection treatment. We discovered Escherichia coli, Salmonella aberdeen, Pseudomonas aeruginosa and Enterococcus faecalis showed diverse resistance to sodium hypochlorite, and transferable RP4 could be released from killed sensitive donor consistently. Meanwhile, the survival of chlorine-tolerant injured bacteria with enhanced cell membrane permeabilisation and a strong oxidative stress-response demonstrated that a physiologically competent cell could be transferred by RP4 with an improved transformation frequency of up to 550 times compared with the corresponding untreated bacteria. Furthermore, the water quality factors involving chemical oxygen demand (COD
), ammonium nitrogen and metal ions (Ca
and K
) could significantly promote above transformation frequency of released RP4 into injured E. faecalis. Our findings demonstrated that the chlorination process promoted the horizontal transfer of plasmids by natural transformation, which resulted in the exchange of ARGs across bacterial genera and the emergence of new ARB, as well as the transfer of chlorine-injured opportunistic pathogen from non-ARB to ARB. Considering that the transfer elements were quite resistant to degradation through disinfection, this situation poses a potential risk to public health.
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