Achieving high loading of active sulfur yet rational regulating the shuttle effect of lithium polysulfide(LiPS)is of great significance in pursuit of high-performance lithium-sulfur(Li-S)***,we develop a free-standing...
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Achieving high loading of active sulfur yet rational regulating the shuttle effect of lithium polysulfide(LiPS)is of great significance in pursuit of high-performance lithium-sulfur(Li-S)***,we develop a free-standing graphene nitrogen(N),phosphorus(P)and fluorine(F)co-doped mesoporous carbon-sulfur(G-NPFMC-S)film,which was used as a binder-free cathode in Li-S *** developed mesoporous carbon(MC)achieved a high specific surface area of 921 m^(2)·g^(-1)with a uniform pore size distribution of 15 *** inserted graphene network inside G-NPFMC-S cathode can effectively improve its electrical conductivity and simultaneously restrict the shuttle of LiPS.A high sulfur loading of 86%was achieved due to the excellent porous structures of graphene-NPFMC(G-NPFMC)*** implemented as a freestanding cathode in Li-S battery,this G-NPFMC-S achieved a high specific capacity(1,356 mAh·g^(-1)),favorable rate capability,and long-term cycling stability up to 500 cycles with a minimum capacity fading rate of 0.025%per cycle,outperforming the corresponding performances of NPFMC-sulfur(NPFMC-S)and MC-sulfur(MC-S).These promising results can be ascribed to the featured structures that formed inside G-NPFMC-S film,as that highly porous NPFMC can provide sufficient storage space for the loading of sulfur,while,the N,P,F-doped carbonic interface and the inserted graphene network help hinder the shuttle of LiPS via chemical adsorption and physical barrier *** proposed unique structure can provide a bright prospect in that high mass loading of active sulfur and restriction the shuttle of LiPS can be simultaneously achieved for Li-S battery.
The molecular orientations of conjugated materials on the substrate mainly include edge-on,face-on,and ***-on and face-on orientations have been widely observed,while end-on orientation has been rarely *** in organic ...
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The molecular orientations of conjugated materials on the substrate mainly include edge-on,face-on,and ***-on and face-on orientations have been widely observed,while end-on orientation has been rarely *** in organic solar cells(OSCs)charge transport is along the vertical direction,end-on orientation with conjugated backbones perpendicular to the substrate is recognized as the ideal microstructure for *** this work,we for the first time obtained the preferential end-on orientation in a conjugated molecular dyad that contains a conjugated backbone as donor and perylene bisimide side units as *** was realized by introducing a fused-ring structure to replace linear terthiophenes with conjugated backbones,yielding F-MDPBI and L-MDPBI ***,a shifting trend of the molecular orientation from dominating edge-on in L-MDPBI to preferential end-on in F-MDPBI was *** a consequence,vertical charge carrier mobilities in F-MDPBI are one order of magnitude higher than those with preferential edge-on orientation,so single-component OSCs based on this molecular dyad as a single photoactive layer provided a power conversion efficiency of 4.89% compared to 1.70% based on L-MDPBI with preferential edge-on orientation.
Advances in research and development of carbon-based metal-free electrocatalysts(C-MFECs)have provided potential alternatives to precious metal catalysts for various reactions important to renewable energy and environ...
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Advances in research and development of carbon-based metal-free electrocatalysts(C-MFECs)have provided potential alternatives to precious metal catalysts for various reactions important to renewable energy and environmental *** timely but critical review provides an overview of recent breakthroughs(within the past 5 years or so)on C-MFECs in all aspects,including the design and regulation of intrinsic catalytic active sites,design and synthesis of carbon composite and hybrid carbon catalysts,mechanism understanding,and potential applications in clean energy storage and energy/chemical *** challenges and future opportunities in the field of metal-free carbon electrocatalysis are also discussed to provide forward-looking opportunities for their potential applications in various catalytic processes of practical significance.
Pre-polymerized vinyl trimethoxy silane(PVTMS)@MWCNT nano-aerogel system was constructed via radical polymerization,sol-gel transition and supercritical CO_(2)*** fabricated organic-inorganic hybrid PVTMS@MWCNT aeroge...
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Pre-polymerized vinyl trimethoxy silane(PVTMS)@MWCNT nano-aerogel system was constructed via radical polymerization,sol-gel transition and supercritical CO_(2)*** fabricated organic-inorganic hybrid PVTMS@MWCNT aerogel structure shows nano-pore size(30-40 nm),high specific surface area(559 m^(2)g^(−1)),high void fraction(91.7%)and enhanced mechanical property:(1)the nano-pore size is beneficial for efficiently blocking thermal conduction and thermal convection via Knudsen effect(beneficial for infrared(IR)stealth);(2)the heterogeneous interface was beneficial for IR reflection(beneficial for IR stealth)and MWCNT polarization loss(beneficial for electromagnetic wave(EMW)attenuation);(3)the high void fraction was beneficial for enhancing thermal insulation(beneficial for IR stealth)and EMW impedance match(beneficial for EMW attenuation).Guided by the above theoretical design strategy,PVTMS@MWCNT nano-aerogel shows superior EMW absorption property(cover all Ku-band)and thermal IR stealth property(ΔT reached 60.7℃).Followed by a facial combination of the above nano-aerogel with graphene film of high electrical conductivity,an extremely high electromagnetic interference shielding material(66.5 dB,2.06 mm thickness)with superior absorption performance of an average absorption-to-reflection(A/R)coefficient ratio of 25.4 and a low reflection bandwidth of 4.1 GHz(A/R ratio more than 10)was experimentally obtained in this work.
The development of Integrated Enset processing technology is significant for the easy availability of stable food in the current condition for fulfilling the pangs of hunger in Ethiopia, currently; individual manual t...
The development of Integrated Enset processing technology is significant for the easy availability of stable food in the current condition for fulfilling the pangs of hunger in Ethiopia, currently; individual manual technologies such as decortication, corm granting, bulla extraction, and fermenting techniques eventually contribute to utilizing food security such as Kocho, which is not affordable for the marginal farmers of Ethiopia. However, there is a lack of integrated compromise of the all-function process of corm granting, decortication, and pulverization in one machine wholesome of the product such as Kocho, and bulla within consuming time and labor. Therefore, it is decided to design and develop an integrated enset processing machine for central high land of Ethiopian farmers with high-quality production. The physical and mechanical properties of the enset is studied to get an efficient and robust design of the various components. The overall design and development of proposed machine components were carried out at Adama science and Technology University, Ethiopia by using ANSYS 2023 R1 software by considering the engineering economics and material specifications as per ASTM standards. The process parameters of the proposed machine are identified as feed rate, drum speed, concave to drum clearance, power requirement, etc. Also, the enset characteristics were considered as decorticating and granting, fiber cutting resistance, fiber length, dimension, shape, and weight. The overall developed enset integrated machine assembles are analyzed for granting and decorticating with drum clearance and bulla extraction throughput capacity, reliability, simplicity, safety, and overall cost. The machine's safety from a Design Perspective is checked and validated by a simulation study on the critical parts subjected to higher stresses. The cost of available individual decorticators, granting, pulverized, and bulla squeezer machines is costly to the farmer’s community. Theref
Through-space conjugation(TSC)is a noncovalently electronic interaction that is emerging as a potential complement to through-bond conjugation(TBC)-based strategies for constructing luminescent ***,the design of effic...
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Through-space conjugation(TSC)is a noncovalently electronic interaction that is emerging as a potential complement to through-bond conjugation(TBC)-based strategies for constructing luminescent ***,the design of efficient luminogens based on TSC is currently challenging due to a lack of established structure-property *** is particularly true in the case of luminogens displaying aggregation-induced emission(AIE)*** this work,three terphenyl derivatives were prepared,and their photophysical properties were systemically *** was found that relative to the corresponding m-and p-linked analogues,the electronic interaction of TBC is weakened while the strength of TSC is commensurately enhanced in the constitutional isomer containing an o-linked fjordtype *** this set of luminogens,the presence of a fjord-type arrangement promotes a transformation from aggregation-caused quenching to *** investigations involving congeneric quaterphenyl and pentphenyl isomers support the universality of the fjord-type unit as a framework for synthesizing AIE-active luminogens(AIEgens)with inherent *** work not only provides a novel set of AIEgens but also establishes the utility of TSC in controlling the photophysical properties of nonconventional and twisted luminogens.
The fiberization and integration of electronic devices into textiles represent an important strategy to design wearable and comfortable intelligent ***,the function realization of existing intelligent textiles often d...
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The fiberization and integration of electronic devices into textiles represent an important strategy to design wearable and comfortable intelligent ***,the function realization of existing intelligent textiles often depends on complex and rigid silicon-based computation components,which have posed significant challenges in terms of integration,energy consumption and user *** has spurred the need for a paradigm shift towards more seamless and efficient *** advent of chipless interactive textile electronics presents a promising pathway for overcoming these challenges and unlocking new possibilities in wearable technology.
In this study, we focus on examining the stability of Al-based inorganic-organic hybrid thin films deposited through the molecular atomic layer deposition (MALD) process in ambient environment. Our observations reveal...
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