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The construction of chemical libraries containing polysubstituted pyrazoline scaffolds is highly desirable for the discovery of novel chemical ligands for biological targets. Herein, we report a sequential DNA-encoded synthesis strategy for polysubstituted pyrazoline heterocycles, which fuses a broad panel of aldehydes, aryl amines, and alkenes as building blocks. Furthermore, mock library synthesis and selection demonstrated the ability of the method to produce DNA-encoded focused libraries with highly functionalized pyrazoline cores.

Layered vanadium oxides have been promising cathodes for rechargeable aqueous zinc ion batteries (AZIBs) owing to multiple valences of vanadium and relatively high interplanar spacing. However, it undergoes significant capacity decay due to vanadium dissolution and structural instability during cycling, especially at low current densities. Herein, PANI-intercalated V2O5 ((PANI)xV2O5, PAVO) hybrid bronzes with an ultra-high interlayer spacing of 13.9 A for use as an AZIB cathode have been reported. The inserted polyaniline not only acts as structural pillars because of the hydrogen bond between -NH2 group and V-O layer but also plays the role of ‘H+’ reservoir to prevent V-O matrix from H+ attacking. Accordingly, PAVO cathode delivers a specific capacity of 350 mAh g−1 with a capacity of ~90% over 100 cycles at a current density of 0.1 A g−1, which operates for about 1 month. This study unveils the dissolution mechanism of vanadium-based electrodes and improves the stability and electronic conductivity with organic molecule intercalation. Besides, the intercalation of guest molecule generates pros and cons (favorable higher interlayer, while adverse steric hindrance) to the Zn2+ diffusion and accordingly presents a different rate performance when compared to most of the previously reported work. Therefore, a new set of molecular-scale hybrid bronzes would be designed to achieve an optimized performance in the future.

Lithium metal-based secondary batteries are very promising for next generation power battery due to their high energy density. However, lithium anodes suffer from poor electrochemical reversibility in organic electrolytes due to Li dendrites and instability of the solid electrolyte interphase. Recent research demonstrated that the problem can be alleviated via tetraethoxysilane (TEOS) treated lithium metal to form a silicon oxide layer on the lithium surface, however, its reaction mechanism is controversial. Herein, we deeply explore the reaction mechanism between TEOS and Li and propose: Fresh Li can directly react with TEOS even though no lithium hydroxide exists on the lithium surface, and the participation of water will accelerate the reaction process. Moreover, it was found that the silicon oxide layer can promote the uniform deposition of lithium ions by providing lithiophilic nucleation sites, thereby achieving a long cycle life of Li metal batteries.

Nitrocellulose (NC) is proposed to stabilize the electrolytes for Li metal batteries. The nitro group of NC preferentially reacts with Li metal, and along with the cellulose skeleton is tightly wrapped on the surface, so that the polymer-inorganic double layer is formed on the Li surface. XPS profile analysis and corroborative cryo-environmental TEM reveal that the flexible outer layer of the bilayer is a C-O organic layer, while the dense inner layer is mainly composed of crystalline lithium oxide, lithium oxynitride, and lithium nitride. The Li deposition process was observed via in situ optical microscopy, which indicated that the NC-derived bilayer facilitates the uniform deposition of Li ions and inhibits the growth of dendrites. After the introduction of NC into the electrolyte, the cycle life of the Li battery is twice than that of the Li battery without NC at 1.0 and 3.0 mA cm-2 .

Reducing carbon dioxide to high value-added chemicals is of high importance due to its vital role in mitigating CO2 emission and energy crisis. However, seeking for robust catalysts with low overpo...

Aqueous redox flow batteries (ARFBs) are regarded as promising candidates for large-scale energy storage. In particular, ARFBs based on organic redox-active species can largely reduce the capital cost and mineral resource requirements. However, the design of redox-active organic materials with desirable electrochemical performances needs to be further explored. Herein, we report a green and low-cost synthesis of a highly soluble N-alkyl-carboxylate-functionalized derivative of 2,6-diaminoanthraquinone, namely, N,N'-(9,10-anthraquinone-2,6-diyl)-di-β-alanine (DAEAQ), which exhibits a high voltage plateau and long cycling life when serving as an anolyte in ARFBs. The alkaline ARFBs based on DAEAQ anolyte and potassium ferrocyanide (K4Fe(CN)6) catholyte deliver a high open-circuit voltage of 1.12 V at pH ≥12. When sandwiched with a custom highly-sulfonated and nonfluorinated cation exchange membrane, the as-prepared ARFBs achieve an excellent maximum power density of 0.34 W cm−2 and an optimal capacity retention rate of 99.86% day−1. This work highlights the great potential of rationally designed anthraquinone derivatives in ARFBs for grid-scale renewable and sustainable energy storage applications.

The conversion of carbon dioxide to chemicals by the electrochemical reactions (ERC) is an efficient solution to the current energy crisis and excess CO2 emissions. It is still a great challenge and of significance to synthesize a highly selective, efficient, and non−noble metal electrocatalyst that facilitates the ERC reaction. A novel triton X−100 (C14H22O(C2H4O)n) assisted electrodeposition method was developed to synthesize the ordered cone−structured tin (OCSn) electrocatalysts with controllable morphology and structure. The results suggest that Triton X−100 plays an important role in directing the structure of the Sn electrocatalysts during the electrodeposition process. The OCSn synthesized at 60 mA cm−2 achieves the best performances. It selectively catalyzes the ERC on the onset potential about 110 mV lower than Sn synthesized without Triton X−100. In 0.5 M NaHCO3, high faradaic efficiency (92%) for formate product on OCSn has been achieved. More prominently, the catalyst presents excellent stability, showing no performance deterioration during 30 h electrolysis. This work provides an efficient, green, and scalable synthesis method of the electrocatalyst for CO2 reduction to formate.

The electrochemical reduction of CO2 (ERC) to valuable chemicals has attracted extensive attention. However, the relatively low selectivity and efficiency of the reaction remain challenges. In this study, Cu electrodes derived from Cu2 O with predominant (111) facets are synthesized by cetyltrimethylammonium bromide-assisted preparation. The optimized electrode shows a high faradaic efficiency of 90 % for HCOOH obtained by ERC at -2.0 V (vs.SCE), which surpasses most reported Cu electrodes. Based on a comprehensive analysis of the relationship between the catalytic activity and the thickness of the Cu2 O layer, the catalytic activity of the unit active site on the Cu2 O-derived Cu electrodes is found to be higher than that on the blank Cu electrode. DFT calculations indicate that OCHO* would be produced preferentially over *COOH in the presence of cetyltrimethylammonium bromide (CTAB). This deduction is verified by testing of the effects of CTAB and KBr addition on HCOO- selectivity.

Aqueous organic flow batteries have attracted dramatic attention for stationary energy storage due to their resource sustainability and low cost. However, the current reported systems can normally be operated stably under a nitrogen or argon atmosphere due to their poor stability. Herein a stable air-insensitive biphenol derivative cathode, 3,3′,5,5′-tetramethylaminemethylene-4,4′-biphenol (TABP), with high solubility (>1.5 mol L−1) and redox potential (0.91 V vs. SHE) is designed and synthesized by a scalable one-step method. Paring with silicotungstic acid (SWO), an SWO/TABP flow battery shows a stable performance of zero capacity decay over 900 cycles under the air atmosphere. Further, an SWO/TABP flow battery manifests a high rate performance with an energy efficiency of 85% at a current density of 60 mA cm−2 and a very high volumetric capacity of more than 47 Ah L−1. This work provides a new and practical option for next-generation practical large-scale energy storage.

The n-octadecyltrichlorosilane (OTS) had been coated onto the layered double hydroxides (LDH), and the resultant composite of OTS-LDH was further loaded on the surface of melamine sponge by a soaking method to obtain the OTS-LDH/melamine sponge for efficient oil adsorption in this work. The surface chemical compositions of the OTS-LDH/sponge and its precursors were characterized by EDS, XPS, and FTIR. The results from EDS, XPS, and FTIR showed that the OTS had been successfully coated on LDH. The surface morphologies from SEM for the melamine sponge before and after modification illuminated that the surface skeleton of the OTS-LDH/sponge took a rough micro-nanostructure, and the surface had been loaded with the low surface energy material of OTS, which made the OTS-LDH/sponge display the superhydrophobic properties. The experiments of oil–water separation proved that the OTS-LDH/sponge took an excellent oil–water efficiency, and the modified sponge still took the better oil–water separation performance with an oil adsorption capacity of 13.7–21.1 times of the mass of the pristine sponge even after undergoing repeated extrusion for 60 times during the repeated cycle test.

A superoleophilic polyurethane sponge had been constructed by means of an immersion method in an ethanol solution of n-octadecyltrichlorosilane. SEM, FTIR, TGA, and XPS unanimously confirmed that PODS had been successfully coated onto the skeleton of polyurethane sponge. The PODS-modified sponge displayed both excellent hydrophobicity with high water contact angle of 152° and good oil affinity. The PODS-modified sponge took the high adsorptive capabilities for the silicone oil, toluene, and peanut oil with 62.1, 73.7, and 98.2 g · g–1 after 50 cycles of extrusion-release, respectively. The superoleophilic sponge in this work exhibited promising opportunities on the oil/water separation and the oil spill remediation.

Plants maintain a dynamic balance between plant growth and stress tolerance to optimise their fitness and ensure survival. Here, we investigated the roles of a clade A type 2C protein phosphatase (PP2C)-encoding gene, OsPP2C09, in regulating the trade-off between plant growth and drought tolerance in rice (Oryza sativa L.). The OsPP2C09 protein interacted with the core components of abscisic acid (ABA) signalling and showed PP2C phosphatase activity in vitro. OsPP2C09 positively affected plant growth but acted as a negative regulator of drought tolerance through ABA signalling. Transcript and protein levels of OsPP2C09 were rapidly induced by exogenous ABA treatments, which suppressed excessive ABA signalling and plant growth arrest. OsPP2C09 transcript levels in roots were much higher than those in shoots under normal conditions. After ABA, polyethylene glycol and dehydration treatments, the accumulation rate of OsPP2C09 transcripts in roots was more rapid and greater than that in shoots. This differential expression between the roots and shoots may increase the plant's root-to-shoot ratio under drought-stress conditions. This study sheds new light on the roles of OsPP2C09 in coordinating plant growth and drought tolerance. In particular, we propose that OsPP2C09-mediated ABA desensitisation contributes to root elongation under drought-stress conditions in rice.

Lithium–sulfur (Li–S) batteries have great potential as an electrochemical energy storage system because of the high theoretical energy density and acceptable cost of financial and environment. However, the shuttle effect leads to severe capacity fading and low coulombic efficiency. Here, graphitic carbon nitride (g–C3N4) is designed and prepared via a feasible and simple method from trithiocyanuric acid (TTCA) to anchor the polysulfides and suppress the shuttle effect. The obtained g–C3N4 exhibits strong chemical interaction with polysulfides due to its high N–doping of 56.87 at%, which is beneficial to improve the cycling stability of Li–S batteries. Moreover, the novel porous framework and high specific surface area of g–C3N4 also provide fast ion transport and broad reaction interface of sulfur cathode, facilitating high capacity output and superior rate performance of Li–S batteries. As a result, Li–S batteries assembled with g–C3N4 can achieve high discharge capacity of 1200 mAh/g at 0.2 C and over 800 mAh/g is remained after 100 cycles with a coulombic efficiency more than 99.5%. When the C–rate rises to 5 C, the reversible capacity of Li–S batteries can still maintain at 607 mAh/g.

The capability to maintain a constant system temperature is vital in nature, since it endows the system with enhanced lifetime. This trait also works for zinc-based batteries, because their cycle-life is limited by notorious zinc dendrite/accumulation, which are highly affected by the inhomogeneous distribution of temperature on electrode and relatively low mechanical strength of membrane. Herein, boron nitride nanosheets (BNNSs) with high mechanical strength serving as heat-porter are introduced onto a porous substrate to enable uniform deposition of zinc and further a zinc-based flow battery with long-cycle life. The results indicate that BNNSs can effectively adjust the deposited zinc from needle-like to French fries-like morphology, thus affording the battery with a stable performance for nearly 500 cycles at 80 mA cm-2 . Most importantly, an energy efficiency of above 80 % can be obtained even at 200 mA cm-2 , which is by far the highest value ever reported among zinc-based flow batteries.

In this work, lithium titanate (Li4Ti5O12)/N-doped carbon/stainless steel mesh (LTO/N-C/SSM) flexible electrodes for Li-ion capacitors were successfully prepared without binder via a facile method ...

[Image: see text] Aztreonam, first discovered in 1980, is an FDA approved, intravenous, monocyclic beta-lactam antibiotic. Aztreonam is active against Gram-negative bacteria and is still used today. The oral bioavailability of aztreonam in humans is less than 1%. Herein we describe the design and synthesis of potential oral prodrugs of aztreonam.

The development of primary batteries with high energy density, long shelf life, and stable discharge voltage is essential for civilization and military applications. Primary batteries with high power output and excellent low-temperature performance can further broaden their application. Herein, a Li/LiV2(PO4)3 primary battery was proposed and investigated for the first time. In order to improve the shelf life of the Li/LiV2(PO4)3 primary battery, the mechanism and corresponding inhibition strategy of self-discharge were studied in detail. It was found that the electrolyte composition is a key factor affecting the shelf life of Li/LiV2(PO4)3 primary batteries, where the corrosion of aluminum (Al) current collector triggered by the organic radical cations generated from electrochemical oxidation of the ethylene carbonate (EC) at high potential; and the detrimental reaction between LiV2(PO4)3 and electrolyte lead to the self-discharge of the Li/LiV2(PO4)3 primary battery. When the EC solvent was replaced by the propylene carbonate (PC) solvent, the corrosion of Al foil was alleviated. Moreover, the addition of lithium bis(oxalato)borate (LiBOB) to the electrolyte could improve the stability of cathode/electrolyte interface and enhance the shelf life of the Li/LiV2(PO4)3 primary battery. As a result, 100% capacity could be maintained after over one-month storage, 86% energy could be maintained at 50C, and 63% energy could be maintained at −40 °C at a current density of 0.1C. In addition, the Li/LiV2(PO4)3 primary battery showed great potential for all-weather applications.

Solar redox flow batteries (SRFBs) integrate solar energy conversion devices and redox flow batteries (RFBs) to realize the flexible storage/utilization of solar energy by charging/discharging redo...

Stimuli-responsive membranes exhibit a flexible adjustment in response to environmental stimuli and have been established many applications. In this paper, dual-stimuli-responsive ultrafiltration m...

Self-assembled ultralong Si 3N 4/SiO 2 nanowires (SiNNWs) with core-shell structure are prepared by air jet-spinning followed by high-temperature calcination employing low-cost fumed nano silica and industrial polyacrylonitrile as raw materials. Without using metal catalysts or reductive atmosphere, Si 3N 4/SiO 2 nanowires are generated through autocatalysis and self-assembly. The ultralong SiNNWs are uniform and continuous throughout the entire length with a 3–4 nm amorphous SiO 2 shell layer on surface of the Si 3N 4. The diameter of the SiNNWs is about 80–200 nm with the length being at centimeter level and the main component of the SiNNWs is the standard hexagonal cell of α-Si 3N 4. Moreover, the photoluminescence spectrum of SiNNWs exhibits an intense blue-green light emission at room temperature. The self-assembly mechanism of the SiNNWs is discussed.

Lithium-sulfur (Li-S) batteries have received extensive attention because of their high theoretical energy density and low cost. However, the low sulfur utilization and the shuttle effect of polysulfide cause low initial capacity and serious capacity decay. Herein, fluorinated graphite (FG) is introduced to the cathode to alleviate these issues. The results indicated that the FG could provide additional capacity during the first discharge process and increase the porosity and polarity of the cathode via in situ formation of lithium fluoride (LiF) nanocrystals, which can enhance the infiltration of electrolyte and polysulfide adsorption. As a result, the as-prepared cathode containing FG shows a high initial specific capacity of 1602 mA h g-1 and the reversible specific capacity is 650 mA h g-1 at 0.5C after 300 cycles. Moreover, its specific capacity remains at 860 mA h g-1 at 5C, which is 367% higher than that of the sample without FG. This paper provides a new strategy to improve the energy density and the cycle stability of Li-S batteries.

Tin oxide (SnOX) nanomaterials have received attention as electrode materials due to their large theoretical capacitance, but their use remains limited due to cumbersome processing and limited electrical conductivity. In this work, SnOX nanoparticles, nanowires and nanorods embedded in a layered composite carbon hybrid nanofiber mat are prepared via blow-spinning followed by pre-oxidation and a high-temperature calcination self-assembly process in argon using stannous chloride and polyacrylonitrile as raw materials. As a result, a dual network conductive structure consisting of an upper SnOx nanostructure and underlying hybrid carbon nanofibers is created. The nanostructure morphology is controlled by reaction time through a transformation from nanoparticle to nanowire and lastly to nanorod and the potential formation and growth mechanism is discussed in detail. It is found that pre-oxidation introduces oxygen in the polyacrylonitrile that upon calcination into carbon nanofibers is released as oxygen containing gaseous substances that fuel transformation and oxidation of stannous chlorides and oxides into the self-assembled stannic oxide nanostructures in an approach applicable to other metal oxide structures. The SnO2 nanowire carbon hybrid nanofibers mat (SnO2–NW@CNFMs) exhibits the highest specific capacitance of 420.1 F g − 1 at a scan rate of 5 mV s − 1 and good cyclic stability of 92.5% capacitance retention after 3000 cycles at 1 A g − 1 which exceeds the performance in earlier reported studies of tin oxide nanomaterials. The high electrochemical properties combined with the novel preparation procedure presented in this study promote SnO2–NW@CNFMs as a good choice for electrodes in electronic appliances and electric vehicles.

Membranes with fast and selective ions transport are highly demanded for energy storage devices. Layered double hydroxides (LDHs), bearing uniform interlayer galleries and abundant hydroxyl groups covalently bonded within two-dimensional (2D) host layers, make them superb candidates for high-performance membranes. However, related research on LDHs for ions separation is quite rare, especially the deep-going study on ions transport behavior in LDHs. Here, we report a LDHs-based composite membrane with fast and selective ions transport for flow battery application. The hydroxide ions transport through LDHs via vehicular (standard diffusion) & Grotthuss (proton hopping) mechanisms is uncovered. The LDHs-based membrane enables an alkaline zinc-based flow battery to operate at 200 mA cm−2, along with an energy efficiency of 82.36% for 400 cycles. This study offers an in-depth understanding of ions transport in LDHs and further inspires their applications in other energy-related devices., Membranes with fast and selective ion transport are highly relevant for energy storage devices. Here, the authors report a layered double hydroxide membrane with high ionic selectivity and hydroxide ion conductivity for flow battery applications, and reveal the ions transport mechanism of the membrane.

A polybenzimidazole (PBI) solvent resistant nanofiltration (SRNF) membrane with super high stability is designed and fabricated by a simple and effective intermolecular cross-linking reaction. There is a dramatic improvement in the solvent stability of the PBI membranes after crosslinking. The membrane keeps stable in even strong apolar solvent like N,N-dimethyl formamide (DMF), N,N-dimethylacetamide (DMAc) after crosslinking. The morphology together with performance can be easily tuned by the polymer concentration. The results indicate that with increasing polymer concentration in cast solution, an increased rejection and a decreased flux are realized. The prepared cross-linked membranes show a rejection of 99% on Rose Bengal (RB) in Ethanol, isopropanol (IPA) and DMF, exhibiting very good prospects in SRNF application. This paper provides a simple and versatile way to create PBI SRNF membranes.

Polybenzimidazole membranes with dual proton transport channels (B-PBI) are designed and fabricated for vanadium flow battery (VFB) applications. The dual channels are established by introducing pyridine groups (channel-1) in the PBI chain (B-PBI), which contains imidazole rings (channel-2). The proton transport channels can endow the B-PBI membrane with dramatically enhanced proton conductivity, while the repulsion between the positively charged pyridine and imidazole nitrogens after doping with protons and the vanadium ions can afford the membrane with excellent ion selectivity. Hence, the prepared B-PBI membrane delivers an excellent performance in terms of high proton conductivity, ion selectivity and chemical stability. A VFB with a B-PBI membrane exhibits a coulombic efficiency (CE) of 99.16% and a voltage efficiency (VE) of 88.86% at a current density of 80 mA cm−2, which is much higher than does a battery with a pristine PBI membrane (CE of 98.54%, VE of 84.10%) and with a Nafion 115 membrane (CE of 95.13%, VE of 87.05%). The chemical stability of the B-PBI is confirmed by a stable performance of 600 cycles at 160 mA cm−2 and the ex-situ oxidation stability test. These results suggest that the B-PBI membrane with dual proton transport channels can be served as promising candidate for vanadium flow battery.

Developing efficient and low-cost catalysts is the key part for electrochemical reduction of CO2, and the bimetallic approach is a cost-effective strategy to find promising electrocatalysts for CO2...

Electrocatalytic reduction of carbon dioxide to high value-added chemicals is essential for sustainable development of human civilization. Seeking catalysts with high activity, selectivity, stabili...

A blend membrane with the core-shell structure was designed and prepared for vanadium flow batteries (VFBs). The core is the membrane manufactured by poly(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP) and polyvinylpyrrolidone (PVP) anion exchange resin, while the shell is composed of cage-shaped pores induced by VO2+ treatment. The high ion selectivity of PVDF-HFP/PVP blend membranes with the core-shell structure is assured by the ion sieving effect of cage-shaped pores and Donnan exclusion effect of anion exchange resin. The convection mechanism of charge carriers across pores on the surface and surface layers, together with the Grotthuss mechanism across the deep-seated anion exchange membrane jointly contributes to high ion conductivity of blend membranes. A great balance between high ion selectivity and high ion conductivity can thus be achieved. Moreover, the formation of cage-shaped pores can remedy the loss of chemical stability caused by anion exchange groups in PVP. A VFB with the resultant membrane could achieve a columbic efficiency of 98.16%, and an energy efficiency of 88.01% at 80 mA cm−2, much higher than those of Nafion 115. This core-shell structural blend membrane is an entirely novel concept to combine advantages of porous membranes and ion exchange membranes, while avoid their drawbacks simultaneously.

An asymmetric structure is the necessary requirement for second-order nonlinear-optical (NLO) materials, which have important applications in modern science and technology. Here we report two isostructural asymmetric compounds, RbBPO4F and CsBPO4F. Both compounds crystallize in cubic space group P213 (No. 198) with three-dimensional (3D) gismondine-like structures. Remarkably, in spite of the same basic structural units BO3F and PO4, both structures are distinct from the previously reported derivative KBPO4F, which crystallizes in a monoclinic space group Cc (No. 9) with a two-dimensional (2D)-layered structure. Careful structural analysis reveals that this structural transformation (from a monoclinic 2D structure to cubic 3D structures) should be aroused by the different alkaline ionic radii. To the best of our knowledge, such an abrupt structural transformation by alkaline elements is reported in all-inorganic asymmetric compounds for the first time. The structural transformation from 2D to 3D structures is favorable to eliminate the layered growth habit. This study will shed deep insight in the structural modulation of asymmetric compounds.

Magnesium ion batteries (MIBs) have attracted significant research attention owing to their low cost, high energy density, and the natural abundance of magnesium. However, lack of compatible cathode materials hinders their further development. Herein, we present a magnesium–lithium hybrid ion battery (MLIB) comprising a Li3V2(PO4)3 (LVP) cathode and magnesium metal anode, where fast reaction kinetics of Li+ ions at the LVP cathode and that of Mg2+ ions at the anode led to high reversible capacities. As a result, a rechargeable MLIB shows excellent rate performance (147.8 and 65.3 mA h g−1 at 50 and 2500 mA g−1 respectively) and capacity retention (99% for 200 cycles), which are the highest values among the reported hybrid batteries using lithium cathodes. To improve temperature adaptability of the designed MLIB, two different kinds of magnesium electrolytes (i.e. all-phenyl-complex and magnesium borohydride in diglyme) and inorganic lithium additives were investigated. It is found that the all-phenyl-complex along with LiCl additives can suppress the freezing of electrolytes effectively even at −40 °C. While, high reversible capacities of 117, 93.4, and 63.1 mA h g−1 can be obtained at 0, −20, and −40 °C respectively, at a current density of 100 mA g−1, showing a very promising prospect for low temperature applications.

A zinc–iodine single flow battery (ZISFB) with super high energy density, efficiency and stability was designed and presented for the first time. In this design, an electrolyte with very high concentration (7.5 M KI and 3.75 M ZnBr2) was sealed at the positive side. Thanks to the high solubility of KI, it fully meets the areal capacity of zinc deposition on the negative side. Most importantly, the ZISFB can be charged to nearly 100% state of charge (SOC) or I− can be fully charged to solid state I2 so as to get a maximum energy density. Besides, the blockage of the pump and pipelines on the positive side caused by solid I2 can be inhibited due to the avoidance of electrolyte circulation. Besides, the employment of a highly composite porous polyolefin ion conducting membrane with a super thin Nafion layer effectively improved the membrane selectivity. As a result, the ZISFB demonstrated a CE of 97% and an EE of 81% at a current density of 40 mA cm−2, and the battery could continuously run for more than 500 cycles. The battery demonstrated a high energy density of 205 W h L−1 (theoretical energy density is about 240 W h L−1) (7.5 M KI and 3.75 M ZnBr2 as the electrolyte), which is the highest cycling energy density ever reported. With super high energy density, long cycling life, and a simple structure, a ZISFB becomes a very promising candidate for large scale energy storage and even for power batteries.

An ultra-high voltage viologen/Br2 flow battery was designed based on a novel two-electron viologen derivative, a highly-conductive and low-cost porous polyolefin membrane, and an effective complexing agent, making the battery one of the most stable two-electron viologen-based flow batteries with superior energy and power density at the same time.

An advanced porous membrane containing slit-like selective layer on its top surface is designed and prepared for flow battery application. The structure is realized by regulating the parameters during membrane formation process. The porous membrane exhibits a thick skin layer with narrow slits and sponge-like support layer in the cross-section. The thick and comparatively hydrophobic skin layer hinders the passage of vanadium ions. Meanwhile, the slit structure and comparatively hydrophilic support layer facilitates the transport of protons. The resulting poly(ether sulfone) (PES)/sulfonated poly(ether ether ketone) (SPEEK) porous membrane containing slit-like selective layer achieves an excellent balance between ion selectivity and proton conductivity, resulting in a columbic efficiency of 98.5%, a voltage efficiency of 91.7%, and an energy efficiency of 90.4% at 80 mA cm−2, which is much higher than a vanadium flow battery (VFB) with the commercial Nafion 115. Therefore, this paper provides a simple and economical method to develop high-performance, low-cost membranes for VFB applications.

Polyetherimide (PEI) porous membranes with tunable morphology are constructed via a typical phase inversion method and applied in lithium-ion batteries (LIBs). The morphology of PEI membranes is adjusted by introducing hydrophilic additives, polyvinyl pyrrolidone (PVP), in the cast solution. The obtained PEI porous membranes show typical sponge-like microstructure and more connected and bigger pores are formed in the membranes with the increase amount of PVP. Under LIBs test condition, batteries with PEI membranes show superior thermal stability, good electrolyte wettability, and tunable ion conductivity and rate performance. As a result, a battery with a PEI-2 membrane exhibited comparable electrochemical performance to that of commercial separators. A 96.4% capacity retention rate was obtained after cycling for 100 cycles for a battery with a PEI-2 membrane. Thus, the membranes with controlled performance in LIBs can be realized via adjusting their morphologies. This paper provides an effective way to optimize fabrication parameters of porous membranes for LIBs application.

Nafion series cation exchange membranes are extensively investigated and applied in proton exchange membrane fuel cells and flow battery technologies because of their excellent stability and easy availability. However, a deep understanding of their ions transport mechanism and behavior under the alkaline based flow battery media is very limited. Here, the ion transport mechanism through Nafion membrane under alkaline medium is investigated by small-angle X-ray scattering and atomic force microscope techniques. The results indicate that a membrane showed a higher degree of phase separation and larger cluster radius in a NaOH solution than those in a KOH solution, which endows the membrane with a much higher ion conductivity in the NaOH solution. Density functional theory-based simulation also indicates that the adsorption and desorption between the Na+ and the –SO3- in Nafion is faster than those of K+. Inspired by these results, an alkaline zinc iron flow battery with a Nafion 212 membrane using NaOH as the supporting electrolyte exhibits a coulombic efficiency of ~ 99% and an energy efficiency of ~ 86% at 80 mA cm−2. This work offers insights into ways to obtain an improved battery performance for the existing as well as the emerging alkaline based flow battery technologies.

Genetic and epigenetic contributions to various diseases and biological processes have been well-recognized. However, simultaneous identification of single-nucleotide variants (SNVs) and DNA methylation levels from traditional bisulfite sequencing data is still challenging. Here, we develop double strand bisulfite sequencing (DSBS) for genome-wide accurate identification of SNVs and DNA methylation simultaneously at a single-base resolution by using one dataset. Locking Watson and Crick strand together by hairpin adapter followed by bisulfite treatment and massive parallel sequencing, DSBS simultaneously sequences the bisulfite-converted Watson and Crick strand in one paired-end read, eliminating the strand bias of bisulfite sequencing data. Mutual correction of read1 and read2 can estimate the amplification and sequencing errors, and enables our developed computational pipeline, DSBS Analyzer (https://github.com/tianguolangzi/DSBS), to accurately identify SNV and DNA methylation. Additionally, using DSBS, we provide a genome-wide hemimethylation landscape in the human cells, and reveal that the density of DNA hemimethylation sites in promoter region and CpG island is lower than that in other genomic regions. The cost-effective new approach, which decodes DNA methylome and genomic variants simultaneously, will facilitate more comprehensive studies on numerous diseases and biological processes driven by both genetic and epigenetic variations.

Compared with the commonly used ester-based electrolytes, more excellent Na+ storage performances can be achieved for hard carbon in the ether-based electrolyte. Whereas, the mysteries underlying such excellent electrochemical performances are still unclear. Herein, the impressive Na+ storage behaviors of hard carbon in the ether-based electrolyte were clarified based on a profound insight of Na+ storage mechanism. It’s revealed that the co-intercalation behavior is responsible for the lower de-solvation energy, which contributes to a facile de-solvation process and the enhanced charge transfer kinetic. Besides, a thin, amorphous and flexible solid-electrolyte interface (SEI) in ether-based electrolyte with a specific structure where the amorphous nanoparticles are coated with organic species was probed. And the resulted SEI is beneficial to achieving much lower activation energy for Na+ diffusion through SEI and a stable interface during cycling due to its excellent ion-conducting ability and mechanical flexibility. It’s also demonstrated that ether-based solvent with short chain length plays a positively impact on the Na+ storages, which also well agrees with the above synergistic effect. The research plays a significant role in elucidating the uniqueness of ether-based electrolytes to hard carbon and promoting its practical application in future sodium-based battery chemistries.

Aqueous organic-based flow batteries are increasingly receiving attention owing to their appealing traits of high safety and low cost. An economic and high-performance membrane is always regarded as the heart of the batteries. Here, we introduce a cost-effective, homemade porous membrane with high performance for alkaline quinone-based flow batteries. The membrane is constituted by highly stable poly(ether sulfone) (PES) and sulfonated poly(ether ether ketone) (SPEEK) that serves dual functions of (1) adjusting the membrane microstructure and (2) endowing the membrane with a charge trait. Benefiting from the well-tuned structure and charge property of the membrane, a high ion selectivity and transport of OH- with much higher mobility serving as the primary charge-balancing ion can be realized. By employing alkaline alizarin red (ARS)/ferro-ferricyanide flow battery as the platform, a battery delivers a coulombic efficiency (CE) of 98.28% and an energy efficiency (EE) of 85.81% at 40 mA cm-2, which is higher than that of the battery with a Nafion 212 membrane (CE ∼ 99.19%, EE ∼ 84.60%), however, with much lower cost. The successful application of homemade porous membrane may provide a new strategy to engineer and fabricate membranes with high efficiency for alkaline quinone-based flow batteries and further decrease the batteries' cost.

Langbeinite-type inorganic compounds have a wide range of applications, but nonlinear-optical properties are rarely mentioned in this series. Here, we report a new orthophosphate, LiCs2Y2(PO4)3, with a langbeinite-type structure, which is the first example in the system of mixed alkali-metal yttrium phosphates. Notably, LiCs2Y2(PO4)3 exhibits a moderate second-harmonic-generation efficiency of 0.9KH2PO4 and is transparent down to 200 nm. In addition, the thermal stability and theory calculations, including the electronic band structure, second-order nonlinear-optical coefficients, and dipole moment analysis, are also reported. This work not only expands the langbeinite-type system but also inspires a study on their nonlinear-optical properties.

The gas separation performance and miscibility of Matrimid and fluorinated sulfonated aromatic poly (ether ether ketone) (F-SPEEK) blend membranes prepared by solution casting method were studied. F-SPEEK polymer with fixed degree of sulfonation (40%) was used for membrane synthesis. Physical miscibility of both Matrimid and F-SPEEK was observed over the whole composition range, as confirmed by DSC studies and visual observation. The effect of variation in F-SPEEK composition on gas permeability and selectivity of blend membranes was investigated. The gas permeability and selectivity values fall in between those of the individual polymers, varying systematically with variation of F-SPEEK content in the blend. The addition of F-SPEEK in the blend led to simultaneous increase in the gas permeability and selectivity. In order to further study the stability and potential industrial application of these membranes, they were tested at different conditions of feed temperature (298–338 K), feed pressures (10–40 bar) and CO2 concentration in feed. The effect of feed pressure on CO2 permeation was linked to CO2 plasticization of the membranes. The addition of F-SPEEK component in the blend shifted the plasticization pressure thereby imparting anti-plasticization properties to the blend. Improvement in anti-plasticization properties along with enhanced gas separation properties confirms F-SPEEK/Matrimid blend membranes as an excellent candidate for the separation of gaseous mixtures at industrial scale.

The development of novel catalysts with both high catalytic activity and low cost toward the hydrolysis of ammonia borane is an important subject in the field of hydrogen energy. In this communications, NixCu1-xO microstructures with different morphology have been synthesized and their catalytic activities in AB hydrolysis is studied. It's found that bracelet-like nanoplatelets were obtained at x = 0.4 and exhibit highest catalytic performance with turnover frequency of 33.43 molhydrogen min-1 mol cat - 1 , which much higher than those of most of CuNi-based catalysts in the literature. Pronounced synergistic effects between CuO and NiO in AB hydrolysis also have been observed. Due to the superior catalytic performance and cheapness, the prepared bracelet-like nanoplatelets Ni0.4Cu0.6O catalysts can be a strong catalyst candidate in AB hydrolysis.

Commercial poly(vinylidene fluoride) (PVDF) membranes were modified by dip-coating and crosslinking hydrophilic poly(vinyl alcohol) (PVA) on the membrane surface. The antioxidation performance of the modified PVDF membranes was evaluated via exposing the modified membranes to sodium hypochlorite and potassium permanganate solutions for 5–30 days, respectively. The evaluation was based on the influences of the two oxidants on the permeability, rejection, and hydrophility of the modified membranes, which were characterized by water flux, ink rejection, water contact angle, x-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy, and x-ray diffraction (XRD) measurements. The XPS and water contact angle results show that the hydrophilicity of PVDF membranes was significantly improved when PVA was crosslinked on the surface of PVDF membranes. When the modified membranes had been treated with sodium hypochlorite or potassium permanganate for 30 days, the permeability and hydrophilicity were basically maintained and the rejection was slightly decreased. XPS and XRD indicated that some of PVAs coated on the membrane surface could be oxidized and peeled.

Electrochemical reduction of CO2 to value-added products is an important and challenging reaction for sustainable energy study. Herein, bismuth nanosheets with thickness of around 10 nm were prepared through the electrochemical reduction of Bi3+ . Ultrathin Bi nanosheets with numerous low-coordination sites can efficiently reduce CO2 to formate in aqueous solution. Within the potential range of -0.9 to -1.2 V vs. reversible hydrogen electrode (RHE), the faradaic efficiency of formate is over 90 %, outperforming many Bi catalysts. At -0.7 V, the Bi nanosheets exhibit much higher current for formate generation than that of bulk Bi, attributed to a high surface area and also modified intrinsic electronic properties brought about by the ultrathin structure. DFT calculations demonstrate that Bi nanosheets have much higher density of states at the Fermi level compared to bulk Bi, favoring improved CO2 reduction on Bi nanosheets. At -1.0 V, Bi nanosheets exhibit high selectivity for formate and excellent stability during 5 h of electrolysis.

The conversion efficiency and product selectivity of the electroreduction of carbon dioxide have been largely limited by the low CO2 solubility in aqueous solution. To relieve this problem, Cu3(BTC)2 (Cu-MOF) as CO2 capture agent was introduced into a carbon paper based gas diffusion electrode (GDE) in this study. The faradaic efficiencies (FEs) of CH4 on GDE with Cu-MOF weight ratio in the range of 7.5–10% are 2–3-fold higher than that of GDE without Cu-MOF addition under negative potentials (−2.3 to −2.5 V vs SCE), and the FE of the competitive hydrogen evolution reaction (HER) is reduced to 30%. This work paves the way to develop GDE with high catalytic activity for ERC.

Lithium–sulfur batteries are promising for next-generation energy storage devices due to the high energy density and low material cost. However, their development is hampered by the short cycling life and severe polarization induced by shuttle effect of polysulfides and sluggish kinetics of Li2S. Herein, for the first time, LiTi2(PO4)2.88F0.12 (LTP-F0.12) is proposed to anchor and activate sulfide based on its strong interaction with lithium polysulfide and rapid charge transfer behavior. By adding 10 wt% LTP-F0.12 to the cathode, the discharge capacity and discharge rate performance were apparently improved, while the capacity retention of about 70% at 0.1C after 200 cycles was realized, which was much higher than that of pure SP–S cathode (lower than 50%). The activation energy (voltage polarization) was decreased by almost 40%. Additional capacity of 132 mA h g−1 was also provided by the LTP-F0.12 from 3.0 to 1.85 V. This study presents a new insight in promoting the polysulfide conversion kinetics in the sulfur cathode.

Solvent treatment has been proved to be a very simple and efficient method to prepare high-performance porous membranes for flow batteries. In this article, the process parameters of solvent treatment were regulated to further investigate the formation mechanism of porous membranes. The effect of the solvent evaporation temperature, the solvent immersion time and the solvent composition on the morphology and performance of porous membranes was studied systematically. The adjustment of these process parameters made the acting mechanisms of the polymer–solvent interaction and the cohesive force of polymers more clear. The factors affecting the polymer–solvent interaction and the cohesive force, along with the acting principles of process parameters, were also elucidated in detail. The formation mechanism of porous membranes during solvent treatment was accordingly clarified distinctly. As a result, an optimized VFB performance of treated membranes with a coulombic efficiency of 98.33%, and an energy efficiency of 81.17% at 160 mA cm−2 was achieved, which was much higher than that of Nafion 115 and among the highest values ever reported. Moreover, this VFB could continually run over 2600 cycles at 200 mA cm−2, without obvious efficiency fade. Thus, this paper provides a simpler, quicker and more economical method to prepare high-performance porous membranes for flow batteries.

Sulfates have long been ignored as nonlinear optical materials over the past decades. Here we report a new sulfate deep-ultraviolet nonlinear optical material Li8NaRb3(SO4)6·2H2O synthesized by the facile water solution method. It crystallizes in the asymmetric monoclinic space group C2 (No. 5). Its single-crystal structure features a three-dimensional framework made up of SO4 and LiO4 tetrahedra. Powder second-harmonic generation tests demonstrate that Li8NaRb3(SO4)6·2H2O is phase-matchable with a second-harmonic generation response of about 0.5 × KH2PO4. Ultraviolet-visible-near-infrared diffuse reflectance spectra illustrate that the ultraviolet cutoff edge of Li8NaRb3(SO4)6·2H2O may be as low as λ < 190 nm. Theoretical calculations reveal that the optical properties of Li8NaRb3(SO4)6·2H2O are mainly attributed to S–O groups. All these results reveal that Li8NaRb3(SO4)6·2H2O may possess potential use in the deep-ultraviolet nonlinear optics field. We believe that the discoveries in our work will attract scientists’ attention to sulfate systems for their potential as deep-ultraviolet nonlinear optical materials.

The rational design of cathode hosts with superior polysulfide (PS) confinement properties, excellent Li+/e− transport and improved cyclability is of the utmost importance for high-areal-capacity lithium–sulfur (Li–S) batteries. Herein, multi-functional nanowall arrays (MNWAs) combining the aforementioned properties are fabricated to improve the electrochemical performance of Li–S batteries with high areal sulfur loadings. The integrated conductive networks and top-down vertically aligned Li+ transport channels are beneficial to Li+/e− transport, resulting in high rate performance with a discharge capacity of 620 mA h g−1 at a high current density of 9.6 mA cm−2 for 4 mg cm−2 sulfur-loaded S/MNWA electrodes. Additionally, the strong PS shuttling suppression via the synergetic effects of physical confinement and chemical adsorption leads to Li–S batteries with a sulfur loading of 10 mg cm−2 capable of delivering a high areal capacity of 12.4 mA h cm−2 with a high capacity retention of nearly 85% for over 100 cycles. What's more, the Li–S batteries assembled with 4 mg cm−2 sulfur-loaded S/MNWA electrodes show an ultra-low capacity decay of 0.07% per cycle over 400 cycles at 3.2 mA cm−2.