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Forthcoming smart energy era is in strong pursuit of full-fledged rechargeable power sources with reliable electrochemical performances and shape versatility. Here, as a naturally abundant/environmentally friendly cellulose-mediated cell architecture strategy to address this challenging issue, a new class of hetero-nanonet (HN) paper batteries based on 1D building blocks of cellulose nanofibrils (CNFs)/multiwall carbon nanotubes (MWNTs) is demonstrated. The HN paper batteries consist of CNF/MWNT-intermingled heteronets embracing electrode active powders (CM electrodes) and microporous CNF separator membranes. The CNF/MWNT heteronet-mediated material/structural uniqueness enables the construction of 3D bicontinuous electron/ion transport pathways in the CM electrodes, thus facilitating electrochemical reaction kinetics. Furthermore, the metallic current collectors-free, CNF/MWNT heteronet architecture allows multiple stacking of CM electrodes in series, eventually leading to user-tailored, ultrathick (i.e., high-mass loading) electrodes far beyond those accessible with conventional battery technologies. Notably, the HN battery (multistacked LiNi0.5Mn1.5O4 (cathode)/multistacked graphite (anode)) provides exceptionally high-energy density (=226 Wh kg−1 per cell at 400 W kg−1 per cell), which surpasses the target value (=200 Wh kg−1 at 400 W kg−1) of long-range (=300 miles) electric vehicle batteries. In addition, the heteronet-enabled mechanical compliance of CM electrodes, in combination with readily deformable CNF separators, allows the fabrication of paper crane batteries via origami folding technique. [ABSTRACT FROM AUTHOR]

The hydrophilicity of the extracellular matrix is one of the most important factors affecting cell adhesion in tissue engineering. In the present study, to improve the cellular biocompatibility of poly( ε -caprolactone) (PCL) nanofiber scaffolds, their surface hydrophilicity was enhanced by electrospinning PCL with biocompatible, amphiphilic poly( N -vinylpyrrolidone)- b -PCL (PVP- b -PCL) block copolymer. The PVP- b -PCL block copolymer ( M n = 26,300 g/mol, M w / M n = 1.14) was synthesized using 2-hydroxyethyl 2-(ethoxycarbonothioylthio)propanoate as a dual initiator for reversible addition–fragmentation chain transfer polymerization and ring opening polymerization in a one-pot procedure. As the content of PVP- b -PCL block copolymer increased, the surface of the PCL/PVP- b -PCL nanofiber scaffolds became more hydrophilic. The scaffolds showed no cytotoxicity, better cell adhesion, and improved viability of primary fibroblasts than PCL scaffolds, and did not lose their structure during cell culture. In particular, the PCL/PVP- b -PCL (90/10, w/w) nanofiber scaffold produced the highest cell viability, suggesting that appropriate scaffold hydrophilicity is required to enhance cell activity. [ABSTRACT FROM AUTHOR]

A new class of highly thin, deformable, and safety-reinforced plastic crystal polymer electrolytes (N-PCPEs) is demonstrated as an innovative solid electrolyte for potential use in high-performance flexible lithium-ion batteries with aesthetic versatility and robust safety. The unusual N-PCPEs are fabricated by combining a plastic crystal polymer electrolyte with a porous polyethylene terephthalate (PET) nonwoven. Herein, the three-dimensional reticulated plastic crystal polymer electrolyte matrix is formed directly inside the PET nonwoven skeleton via in-situ UV-crosslinking of ethoxylated trimethylolpropane triacrylate (ETPTA) monomer, under co-presence of plastic crystal electrolyte. The PET nonwoven is incorporated as a compliant skeleton to enhance mechanical/dimensional strength of N-PCPE. Owing to this structural uniqueness, the N-PCPE shows significant improvements in the film thickness and deformability with maintaining advantageous features (such as high ionic conductivity and thermal stability) of the PCE. Based on structural/physicochemical characterization of N-PCPE, its potential application as a solid electrolyte for flexible lithium-ion batteries is explored by scrutinizing the electrochemical performance of cells. The high ionic conductance of N-PCPE, along with its excellent deformability, plays a viable role in improving cell performance (particularly at high current densities and also mechanically deformed states). Notably, the cell assembled with N-PCPE exhibits stable electrochemical performance even under a severely wrinkled state, without suffering from internal short-circuit failures between electrodes. [ABSTRACT FROM AUTHOR]

Summary: Quantum dots (QDs) are luminescent nanoparticles with unique optical properties that have been exploited for single-cell and whole-animal imaging. When coated with proteins or biocompatible polymers, QDs are not deleterious to cells and organisms. However, when QDs are retained in cells or accumulated in the body for a long period of time, their coatings may be degraded, yielding “naked” QDs. Here, we show that “naked” QDs induce damage to the plasma membrane, mitochondrion, and nucleus, leading to cell death. Reactive oxygen species (ROS) are important players in mediating QD-induced cellular damage. QD-induced cytotoxicity can be reduced or even eliminated without covalent binding of protective agents to the QD surface. Results from these studies suggest the critical role of several subcellular compartments in QD-induced cytotoxicity and point toward multiple molecular targets in nonclassical apoptosis. [Copyright &y& Elsevier]

Silica solid substrates such as fused silica, silicon wafers with a natural oxide layer, and glass were treated with aziridine to produce reactive primary amine groups on the top surface. We found that the hydroxyl group on the substrate was able to initiate the ring-opening polymerization of aziridine, resulting in highly branched poly(ethyleneimine) on the surface. In dichloromethane, the thickness of the organic film reached 25 A˚ in 20 h and the absolute density of the primary amine group on the surface was 23 amines/nm2. Atomic force microscopy shows an embossed morphology after the polymerization in dichloromethane, while use of toluene gives a rather smooth surface. The resulting organic layer shows high thermal and pH stability. [Copyright &y& Elsevier]

Explores the scope of an azomethine ylide-forming photoreaction by probing the excited state chemistry of N-trimethylsilylmethyl substituted cyclic and acyclic imides and amide analogs. Photolysis of N-[(trimethylsilyl)methyl]maleimide; Irradiation in solutions with high concentrations of dipolarophiles; Electrocyclization of ylides to form transient aziridine intermediates.

The first synthesis of a triphenylmethine (TM) library of compounds and screening of their Surface Enhanced Raman Scattering (SERS) capability was carried out to identify novel Raman reporters with high sensitivity. We identified three novel SERS reporters (B2, B7, and C7) with higher signal intensity than that of commonly used crystal violet (CV). These reporters may find potential applications in developing sensitive SERS based biosensors. [ABSTRACT FROM AUTHOR]

The discovery of a reliable electrolyte system remains one of the key challenges for the development of advanced lithium–oxygen batteries. To date, no single electrolyte is verified to be stable and compatible with both the cathode (e.g., oxygen radicals, lithium peroxide, etc.) and anode (lithium metal) for lithium–oxygen batteries. In this work, a novel liquid‐based Janus electrolyte system consisting of two different immiscible liquid phases is proposed and it is demonstrated that this system is remarkably effective in promoting the sustainable operation of redox‐mediated lithium–oxygen batteries. The liquid‐based Janus electrolyte is rationally designed by considering its compatibility with the lithium–oxygen cell environment, the solubility difference of target soluble species, and the mutual immiscibility of the two liquid phases. By combining spectral characterization, a phase‐separation experiment, and in situ observation of the electrochemical cell, it is revealed that the liquid‐based Janus electrolyte suppresses the migration of redox mediators from one liquid phase to the other, thereby preventing the detrimental shuttle effect. The enhanced stability of redox mediation leads to improved cycling performance of the cell. The various combinations possible for the liquid‐based Janus electrolyte open a new unexplored pathway for the design of advanced electrolyte systems for lithium–oxygen batteries. [ABSTRACT FROM AUTHOR]

We examine the impact of current and future climate on crop mixes over space in the US. We find using historical data that temperature and precipitation are among the causal factors for shits in crop production location and mixes, with some crops being more sensitive than others. In particular, we find that when temperature rises, cotton, rice, sorghum and winter wheat are more likely to be chosen. We also find that barley, sorghum, winter wheat, spring wheat and hay are more likely to be chosen as regions become drier, and corn, cotton, rice and soybeans are more likely to be selected in wetter regions. Additionally, we assess how much of the observed crop mix shifts between 1970 and 2010 were contributed to by climate change. There we find climate explains about 7-50% of the shift in latitude, 20-36% in longitude and 4-28% of that in elevation. Finally, we estimate climate change impacts on future crop mix under CMIP5 scenarios. There we find shifts in US production regions for almost all major crops with the movement north and east. The estimates describe how the farmers respond to altering climate and can be used for planning future crop allocations. [ABSTRACT FROM AUTHOR]

On page 6029, S.‐Y. Lee, S.‐Y. Lee, and co‐workers present cellulose nanofibril/multiwall carbon nanotube‐based hetero‐nanonet paper batteries as 1D material‐mediated cell architectures to enable ultrahigh energy density and shape versatility far beyond those achievable with conventional battery technologies. Benefiting from 3D bicontinuous electron/ion transport pathways and exceptional mechanical compliance, the hetero‐nanonet paper batteries provide unprecedented improvements in the electrochemical reaction kinetics, energy density, and origami foldability. [ABSTRACT FROM AUTHOR]

Thin, deformable, and safety‐reinforced plastic crystal polymer electrolytes for use in high‐performance flexible lithium‐ion batteries with aesthetic versatility and robust safety features is reported on page 44 by S.‐Y. Lee and co‐workers. The combination of a plastic crystal polymer electrolyte matrix with a compliant nonwoven skeleton enables the fabrication of the innovative polymer electrolyte with optimized attributes. The cell assembled with the polymer electrolyte exhibits stable electrochemical performance under severely deformed states (even a wrinkled state), without suffering from internal short‐circuit failures. [ABSTRACT FROM AUTHOR]

Abstract: Anti-glycation activity of our anti-oxidant quinone library was measured and several 2,3-dimethoxy-5-methyl-1,4-benzoquinones and 2-methyl-1,4-naphthoquinones were identified as novel inhibitors of glycation, of which 2,3-dimethoxy-5-methyl-1,4-benzoquinones 13b is the most potent glycation inhibitor with around 50μM of the IC50 value. [Copyright &y& Elsevier]

The inability to guide the nucleation locations of electrochemically deposited Li has long been considered the main factor limiting the utilization of high‐energy‐density Li‐metal batteries. In this study, an electrical conductivity gradient interfacial host comprising 1D high conductivity copper nanowires and nanocellulose insulating layers is used in stable Li‐metal anodes. The conductivity gradient system guides the nucleation sites of Li‐metal to be directed during electrochemical plating. Additionally, the controlled parameter of the intermediate layer affects the highly stable Li‐metal plating. The electrochemical behavior is confirmed through experiments associated with the COMSOL Multiphysics simulation data. The distributed Li‐ion reaction flux resulting from the controlled electrical conductivity enables stable cycling for more than 250 cycles at 1 mA cm−2. The gradient system effectively suppresses dendrite growth even at a high current density of 5 mA cm−2 and ensures Li plating and stripping with ultra‐long‐term stability. To demonstrate the high‐energy‐density full‐cell application of the developed anode, it is paired with the LiNi0.8Co0.1Mn0.1O2 cathode. The cells demonstrate a high capacity retention of 90% with an extremely high Coulombic efficiency of 99.8% over 100 cycles. These results shed light on the formidable challenges involved in exploiting the engineering aspects of high‐energy‐density Li‐metal batteries. [ABSTRACT FROM AUTHOR]

Keywords: all-solid-state Li-sulfur batteries; bipolar configuration; immiscible gel electrolytes; nonflammability; printing In article number 1901841, Sang-Young Lee and co-workers fabricate all-solid-state printed bipolar Li-S batteries via a solvent-drying-free, ultraviolet curing-assisted stepwise printing process under ambient conditions. All-solid-state Li-sulfur batteries, bipolar configuration, immiscible gel electrolytes, nonflammability, printing. [Extracted from the article]

Despite their potential advantages over currently widespread lithium‐ion batteries, lithium–sulfur (Li–S) batteries are not yet in practical use. Here, for the first time bipolar all‐solid‐state Li–S batteries (ASSLSBs) are demonstrated that exhibit exceptional safety, flexibility, and aesthetics. The bipolar ASSLSBs are fabricated through a solvent‐drying‐free, ultraviolet curing‐assisted stepwise printing process at ambient conditions, without (high‐temperature/high‐pressure) sintering steps that are required for inorganic electrolyte‐based all‐solid‐state batteries. Two thermodynamically immiscible and nonflammable gel electrolytes based on ethyl methyl sulfone (EMS) and tetraethylene glycol dimethyl ether (TEGDME) are used to address longstanding concerns regarding the grain boundary resistance of conventional inorganic solid electrolytes, as well as the polysulfide shuttle effect in Li–S batteries. The EMS gel electrolytes embedded in the sulfur cathodes facilitate sulfur utilization, while the TEGDME gel composite electrolytes serve as polysulfide‐repelling separator membranes. Benefiting from the well‐designed cell components and printing‐driven facile processability, the resulting bipolar ASSLSBs exhibit unforeseen advancements in bipolar cell configuration, safety, foldability, and form factors, which lie far beyond those achievable with conventional Li–S battery technologies. [ABSTRACT FROM AUTHOR]

The excellent stability of sulfide solid electrolytes with solvate ionic liquids Li(triethylene glycol dimethyl ether)bis(trifluoromethanesulfonyl)imide (Li(G3)TFSI), and their application for high‐performance, all‐solid‐state lithium‐ion batteries are successfully demonstrated. The addition of a small amount of Li(G3)TFSI gives an alternative ionic pathway through normally poor solid–solid contacts, leading to a dramatic increase in LiFePO4 composite electrode capacity. [ABSTRACT FROM AUTHOR]

A series of tetraphenylcyclopenta-2,4-dienones with various substituents including hydrogen, thiophene and methoxy groups were prepared to compare their suitability as materials for forming alkali metal- based (Li or Na) solvated electron solutions (SESs) for potential use as anode materials for flow Li-Air (or Na) batteries at ambient temperature condition. The materials are amorphous, not luminescent and have moderate E g, opt in range 1.84–1.91 eV. They also possess good thermal stability (stable above 200 °C), exhibit quasi-reversible reduction and oxidation reactions. It was also found that the type of substituent can influence the ability of the cyclopentadienones to form SES with alkali metals, where the derivatives with hydrogen or methoxy units were found to form SESs with lithium, but the thienyl derivative did not. Parallel studies also indicated that our big π-systems were thermodynamically more favorably to solvate the electrons than small and simple aromatic or polar aprotic solvent molecules such as benzene, toluene, xylene, tetrahydrofuran, solvate acetone, etc. [ABSTRACT FROM AUTHOR]

ABSTRACT Amphiphilic, biocompatible poly( N-vinylpyrrolidone)- b-poly( l-lactide) (PVP- b-PLLA) block polymers were synthesized at 60 °C using a hydroxyl-functionalized N,N-diphenyldithiocarbamate reversible addition-fragmentation chain transfer (RAFT) agent, 2-hydroxyethyl 2-( N,N-diphenylcarbamothioylthio)propanoate (HDPCP), as a dual initiator for RAFT polymerization and ring-opening polymerization (ROP) in a one-step procedure. 4-Dimethylamino pyridine was used as the ROP catalyst for l-lactide. The two polymerization reactions proceeded in a controlled manner, but their polymerization rates were affected by the other polymerization process. This one-step procedure is believed to be the most convenient method for synthesizing PVP- b-PLLA block copolymers. HDPCP can also be used for the one-step synthesis of poly( N-vinylcarbazole)- b-PLLA block copolymers. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 1607-1613 [ABSTRACT FROM AUTHOR]

Abstract: As a facile and scalable approach to the surface modification of high-voltage cathode materials for lithium-ion batteries, direct UV-assisted conformal coating of poly(tris(2-(acryloyloxy)ethyl) phosphate) (PTAEP) gel polymer electrolyte on as-formed LiNi1/3Co1/3Mn1/3O2 (NCM) cathode is presented. The smooth and continuous PTAEP coating layer with nanometer-thickness (∼20 nm) is successfully introduced on the NCM surface without impairing electronic/ionic conduction pathways preformed in the NCM cathode. Owing to this structural uniqueness, the PTAEP-coated NCM cathode significantly improves the high-voltage (4.6 V) cycling performance and mitigates the exothermic reaction between the delithiated NCM and liquid electrolyte. This demonstrates that the conformal PTAEP nanocoating layer proposed herein, which is completely different from conventional inorganic material-based coating layers, acts as a new ion-conductive protective film that effectively suppresses unwanted interfacial side reactions between the high-voltage cathode materials and liquid electrolyte. [Copyright &y& Elsevier]

Electrical Conductivity Gradients: Electrical Conductivity Gradient Based on Heterofibrous Scaffolds for Stable Lithium-Metal Batteries (Adv. Funct. Keywords: cellulose nanofibers; copper nanofiber scaffolds; electrical conductivity gradients; lithium metal anodes; stable plating EN cellulose nanofibers copper nanofiber scaffolds electrical conductivity gradients lithium metal anodes stable plating 1 1 1 04/08/20 20200403 NES 200403 In article number 1908868, Hyun-Wook Lee, Ki-Suk Lee, Sang-Young Lee, and co-workers present an electrical conductivity gradient interfacial host comprising 1D high conductivity copper nanowires and nanocellulose insulating layers for stable lithium metal anodes. Cellulose nanofibers, copper nanofiber scaffolds, electrical conductivity gradients, lithium metal anodes, stable plating. [Extracted from the article]

Bulk‐type all‐solid‐state lithium batteries are highly promising candidates for large scale energy storage applications because of their superior safety. In article 1500865, Yoon Seok Jung and co‐workers demonstrate a strategy to obtain a dramatically improved performance by ensuring favorable ionic contacts. This is acheived via the addition of a small amount of solvate ionic liquids (Li(G3)TFSI), which demonstrate excellent compatibility with the sulfide solid electrolyte in composite electrodes. [ABSTRACT FROM AUTHOR]