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A new tyramine derivative, glycosamide A (1), together with two known amide alkaloids, N-benzoyltyramine methyl ether (2) and aurantiamide acetate (3), was isolated from the branches and leaves of Glycosmis craibii Tanaka. Their structures were elucidated through extensive 1D and 2D NMR and HR-ESI-MS spectroscopic analyses. All known compounds were isolated from the genus Glycosmis for the first time. Furthermore, the antiproliferative activities of all isolated alkaloids in vitro were evaluated. Compound 2 displayed weak antiproliferative activities against five human cancer cell lines, HL-60, SMMC-7721, A-549, MCF-7, and SW480.

Two new aldoximes A–B (1−2), and two known analogues (3−4), were identified from ethanolic extracts of Glycosmis craibii. The structures of new compounds 1−2 were unambiguously elucidated based on spectroscopic methods. All isolated aldoximes were evaluated for their anti-inflammatory activity in vivo. Compounds 1−4 displayed remarkable inhibitory effects against nitric oxide (NO) production stimulated by lipopolysaccharide in mouse macrophage RAW 264.7 cells with the IC50 values ranging from 2.38 ± 0.08–8.43 ± 0.21 μM.

Carrier recombination and charge loss at the interfaces of perovskite layers have a significant influence on high-performance planar perovskite solar cells (PSCs). We employed two-dimensional graphitic carbon nitride (g-C3N4), which is a heat-resistant n-type semiconductor, to modify the electron-transport layer/perovskite and perovskite/hole-transport layer interfaces, respectively. g-C3N4 could passivate the surface trap states of the methylammonium lead iodide light absorber through the formation of a Lewis adduct between N and the under-coordinated Pb, and it could also remarkably reduce the grain boundaries between perovskite crystal particles. A maximum power conversion efficiency (PCE) of 19.67% (Voc = 1.14 V, Jsc = 21.45 mA cm−2, FF = 0.807) could be obtained from planar PSCs with long-term stability using dual-positioned g-C3N4. Therefore, we consider that ultrathin semiconductor films with a Lewis base nature are suitable as dual-functional transport materials for devices. This work provides new guidance for dual-interfacial modification to improve the PCE and stability of devices.

Hydrogen energy, as an ideal renewable resource and green energy replacement, has attracted growing attention. However, constructing highly active and stable catalysts for hydrogen evolution from Formic acid (FA) is still a challenging issue for development of renewable hydrogen energy. Herein, we develop a facile defect engineering strategy to construct N-deficient ordered mesoporous graphitic carbon nitride coupled with AgPd nanoparticles (denoted as AgPd/N-ompg-C3N4). Impressively, the as-prepared Ag0.1Pd0.9/N-ompg-C3N4 catalyst exhibits remarkable activity with the Turnover frequency (TOF) value of 1588.2 h−1 and robust stability with only a slight decrease in activity after ten cycles. Such markedly enhanced catalytic performance of Ag0.1Pd0.9/N-ompg-C3N4 is mainly attributed to the unique structure of N-ompg-C3N4 with higher surface area and abundant surface defects, the strong metal − support interaction between AgPd and N-ompg-C3N4, and charge transfer from Pd to Ag. This study provides a novel and efficient strategy for designing efficient catalysts to drive the hydrogen evolution from FA.

Hydrous hydrazine (N2H4∙H2O) is a candidate for a hydrogen carrier for storage and transportation due to low material cost, high hydrogen content of 8.0%, and liquid stability at room temperature. Pt and Pt nanoalloy catalysts have been welcomed by researchers for the dehydrogenation of hydrous hydrazine recently. Therefore, in this review, we give a summary of Pt nanoalloy catalysts for the dehydrogenation of hydrous hydrazine and briefly introduce the decomposition mechanism of hydrous hydrazine to prove the design principle of the catalyst. The chemical characteristics of hydrous hydrazine and the mechanism of dehydrogenation reaction are briefly introduced. The catalytic activity of hydrous hydrazine on different supports and the factors affecting the selectivity of hydrogen catalyzed by Ni-Pt are analyzed. It is expected to provide a new way for the development of high-activity catalysts for the dehydrogenation of hydrous hydrazine to produce hydrogen.

The removal of cationic dyes, methylene blue(MB) and rhodamine B(RB), and anionic dyes, methyl orange(MO) and eosin Y(EY), from aqueous solutions by adsorption using Cu2Se nanoparticles(Cu2SeNPs) was stu-died. The effects of the initial pH values, adsorbent doses, contact time, initial dye concentrations, salt concentrations, and operation temperatures on the adsorption capacities were investigated. The adsorption process was better fitted the Langmuir equation and pseudo-second-order kinetic model, and was spontaneous and endothermic as well. The adsorption mechanism was probably based on the electrostatic interactions and π-π interactions between Cu2SeNPs and dyes. For an adsorbent of 0.4 g/L of Cu2SeNPs, the adsorption capacities of 23.1(MB), 22.9(RB) and 23.9(EY) mg/g were achieved, respectively, with an initial dye concentration of 10 mg/g(pH=8 for MB and pH=4 for RB and EY) and a contact time of 120 min. The removal rate of MB was still 70.4% for Cu2SeNPs being reused in the 5th cycle. Furthermore, the recycled Cu2SeNPs produced from selenium nanoparticles adsorbing copper were also an ef-fective adsorbent for the removal of dyes. Cu2SeNPs showed great potential as a new adsorbent for dyes removal due to its good stability, functionalization and reusability.

Short DNA represents an important class of biomacromolecules that are widely applied in gene therapy, editing, and modulation. However, the development of simple and reliable methods for their intracellular delivery remains a challenge. Herein, we describe that seven water-soluble, homogeneous supramolecular organic frameworks (SOFs) with a well-defined pore size and high stability in water that can accomplish in situ inclusion of single-stranded (ss) and double-stranded (ds) DNA (21, 23, and 58 nt) and effective intracellular delivery (including two noncancerous and six cancerous cell lines). Fluorescence quenching experiments for single and double end-labeled ss- and ds-DNA support that the DNA sequences can be completely enveloped by the SOFs. Confocal laser scanning microscopy and flow cytometry reveal that five of the SOFs exhibit excellent delivery efficiencies that, in most of the studied cases, outperform the commercial standard Lipo2000, even at low SOF–nucleic acid ratios. In addition to high delivery efficiencies, the water-soluble, self-assembled SOF carriers have a variety of advantages, including convenient preparation, high stability, and in situ DNA inclusion, which are all critical for practical applications in nucleic acid delivery.

SnO2 has attracted extensive attention in planar perovskite solar cells (PSCs) owing to its outstanding photoelectric properties and low temperature preparation. However, pinholes are easy to appear in the annealing process of SnO2 films, which limits its application in planar PSCs. Here lists a simple and low-cost method: Urea-complexed tin oxide in deionized water can effectively control the concentration of SnO2. This process is conducive to forming a compact surface morphology. Meanwhile, the work explored the effect of the properties of PSCs with different thicknesses of SnO2 layers. The system analysis showed that PSCs based on 60 nm SnO2 layer and the methamphetamine lead iodide (MAPbI3) light absorber yielded the highest power conversion efficiency (PCE) over 18%, a fill factor (FF) of 0.793, and good stability. Therefore, we believe our study provides an effective way for preparing electron transport layers.

The battery industry is constantly seeking to improve battery capacity, lifetime, and safety. Electrolytes are a key development focus in achieving these goals, as traditional carbonate-based electrolytes cause capacity fade and gassing through degradation processes, as well as representing a safety risk due to flammability. The release of gasses through electrolyte decomposition is a problem of prominent concern in the battery industry, due to the negative impact of gassing on cell safety and performance. Studies on battery gassing have been reported for a wide range of battery systems,1-3 but the mechanisms and conditions of gas release are complex and not fully understood. Gaining a greater understanding of gassing mechanisms, and the specific electrolyte components that cause them, will allow for precise design of battery electrolyte formulations that optimize performance and minimize gassing. In addition to understanding traditional electrolyte blends, the investigation of new electrolytes and additives is essential in developing low-gassing batteries. Organosilicon (OS) materials have been developed by Silatronix® as critical high stability additions to conventional carbonate electrolytes to enable next-generation Li-ion batteries. This novel organosilicon chemistry involves the merging of a silane with a Li+ coordinating functionality. For example, the OS3® solvent family contains a nitrile functionality. The adoption of new Li-ion battery electrolyte materials is driven by the desire to deploy higher energy density batteries capable of performing under broader operating conditions of temperature and voltage, and the design of OS solvents results in low molecular-weight molecules that have demonstrated superior thermal and electrochemical stability,4,5 as well as good safety properties with a high flash point and low vapor pressure. Silatronix® has conducted commercially relevant performance testing and fundamental mechanistic studies to investigate gassing phenomena in advanced Li-ion chemistries under both cycling and storage test conditions. In these studies, commercially relevant electrolytes were evaluated as well as electrolytes designed to specifically isolate the effect of selected electrolyte components, including OS3® and other industry-relevant solvents. The dependence of gassing on storage and voltage conditions was investigated, and connections between gas analysis and the electrode surface chemistry are also reported. Gas component analysis was performed with a calibrated dual-column GC-TCD, a similar analytical system to that utilized in previous studies,6 which provides excellent resolution and quantification of every gaseous product. Key experimental results show that all OS3® concentrations reduce gas generation after 60°C storage and higher OS3® content provides greater benefit. Overall, we show that organosilicon additives substantially reduce gassing from carbonate-based electrolytes while maintaining good cell performance. Zhang, S.S., Insight into the Gassing Problem of Li-ion Battery. Frontiers in Energy Research 2014, 2, 59. Self, J.; Aiken, C.P.; Petibon, R.; Dahn, J.R., Survey of Gas Expansion in Li-Ion NMC Pouch Cells. Journal of the Electrochemical Society 2015, 162, A796-A802. Jung, R.; Metzger, M.; Maglia, F.; Stinner, C., Chemical vs Electrochemical Electrolyte Oxidation on NMC111, NMC622, LNMO, and Conductive Carbon. The Journal of Physical Chemistry Letters 2017, 8, 4820-4825. Guillot, S.L.; Peña-Hueso, A.; Usrey, M.; Hamers, R.J., Thermal and Hydrolytic Decomposition Mechanisms of Organosilicon Electrolytes with Enhanced Thermal Stability for Lithium-Ion batteries. Journal of the Electrochemical Society 2018, 164, A1907-A1917. Chen, X.; Usrey, M.; Peña-Hueso, A.; West, R.; Hamers, R.J., Thermal and Electrochemical Stability of Organosilicon Electrolytes for Lithium-Ion Batteries. Journal of Power Sources 2013, 241, 311-319. Xiong, D.J.; Ellis, L.D.; Petibon, R.; Hynes, T.; Liu, Q.Q.; Dahn, J.R., Studies of Gas Generation, Gas Consumption and Impedance Growth in Li-Ion Cells with Carbonate or Fluorinated Electrolytes Using the Pouch Bag Method. Journal of the Electrochemical Society 2017, 164, A340-A347.

Intermolecular Stetter reaction of aromatic aldehydes with (E)-(2-nitrovinyl)cyclohexane catalyzed by thiazolium A has been developed. The reaction rate and efficiency are profoundly impacted by the presence of thiourea B. The reaction affords moderate to good yields of the Stetter product. Some factors influencing yield were discussed.

A novel series of lithium alkyl trimethyl borates and lithium aryl trimethyl borates have been prepared and investigated as cathode film forming additives. The borates are prepared via the reaction of lithium alkoxides or lithium phenoxides with trimethyl borate. Incorporation of 0.5–2.0% (wt) of the lithium borates to a baseline electrolyte (1.0 M LiPF6 in 3 : 7 (EC/EMC)) results in improved capacity retention and efficiency of high voltage graphite/LiNi0.5Mn1.5O4 cells especially upon cycling at elevated temperature (55 °C). The improved performance results from the sacrificial oxidation of the lithium borate on the cathode surface to generate a cathode passivation film. The lithium borates can be readily structurally modified to act as a functional group delivery agent to modify the cathode surface. Ex situ surface analysis of the electrodes after cycling confirms that the lithium borates modify the cathode surface and generate a borate rich surface film which inhibits electrolyte oxidation and Mn dissolution.

Six polyphenolic acids (1-6), including the three new compounds citriodolic acids A, B, and C (1-3), were isolated from the leaves of Eucalyptus citriodora. Their structures were elucidated by spectroscopic methods including one dimensional (1D)- and 2D-NMR, high-resolution electrospray ionization (HR-ESI)-MS, and circular dichroism (CD). The potential antivirus activity against respiratory syncytial virus (RSV) of all the isolated compounds was evaluated.

Two dimensional graphitic carbon nitride nanosheets (2D CNNs), as novel types of emerging materials, have aroused considerable research enthusiasm in recent years. Herein, we describe for the first time a new application of 2D CNNs as an ideal scaffold for synthesizing AgPd/2D CNNs through a facile one-step reduction method and further utilized it as catalysts toward photocatalytic hydrogen generation from FA under visible light (λ > 400 nm). Benefiting from plasmonic and Mott-Schottky, alloying effects, as well as the unique 2D nanosheets structure with a high surface area, the resultant Ag0.1Pd0.9/2D CNNs affords superior performance under visible light, including 100% H2 selectivity, 100% conversion, cycle performance, hydrogen evolution rate of 231.6 mmol h−1and the corresponding TOF value of 2936.8 h−1, which is 1.87 times and 3.5-fold higher than that of Ag0.1Pd0.9/2D CNNs under no light (1573.5 h−1) and that of Ag0.1Pd0.9/CN (837.2 h−1) under visible light, respectively, even better than most of the noble metal heterogeneous catalysts. This study not only throws light on modulating the structure of g-C3N4 to enhance the photocatalytic activity toward hydrogen evolution reaction but also offers a versatile method for developing high-performance photocatalyst for hydrogen economy and other applications.

Depression is the most common psychiatric comorbidity in patients. Searching for antidepressant drugs from natural products is very important for the treatment of this disease. The ethanol extract and its fractions of Cyperus rotundus were evaluated for antidepressant activities in mice by our group. The aim of this study was to investigate the potential active components of C. rotundus. The extraction and solvent partition of the rhizomes of C. rotundus, and repeated column chromatography for n-BuOH fraction yielded three new phenolic glycosides, rotunduside D (1), rotunduside E (2), and rotunduside F (3). Their chemical structures were identified on the basis of spectroscopic data analyses including NMR, MS, UV, and IR. The potential antidepressant activity of all the isolated compounds was evaluated. In the despair mice models, rotunduside F (3) showed significant antidepressant activity at the dosage of 50 mg/kg, which was close to the positive control fluoxetine (20 mg/kg).

The ionic conductivity of LiBOB-doped electrolytes containing two silyl solvents, bis[2-(2-methoxyethoxy)ethoxy] dimethylsilane, 1, and [2-(2-methoxyethoxy)ethoxy] trimethylsilane,2, was measured from −10 °C to 50 °C using AC impedance spectroscopy to assess their potential use in commercial Li-ion cells. The effects of salt concentration, solvent composition, and temperature on the conductivity of the electrolytes are reported. In addition, conductivity data were fit using the Vogel-Tamman-Fulcher (VTF) equation to obtain the parameters σ0, T0, and Ea, which correspond closely to conductivity and viscosity. All the electrolytes produced conductivities above the 1.0 mS cm−1 threshold required for commercial application. The 1:1 (vl) solvent composition possesses the highest conductivity, with the optimal 0.8 M salt-loading yielding the highest σ25 at 1.99 ± 0.02 mS cm−1.

Intermolecular Stetter reaction of aromatic aldehydes with (E)-(2-nitrovinyl)cyclohexane catalyzed by thiazolium A has been developed. The reaction rate and efficiency are profoundly impacted by the presence of thiourea B. The reaction affords moderate to good yields of the Stetter product. Some factors influencing yield were discussed.

Novel tricyclic fluoroquinolones, [1,2,4]triazolo[3,4-h][1,8]naphthyridine-8-one-7-carboxylic acid derivatives 4a – 4h bearing carrying a functional Mannich-base moiety at the C-8 position, were synthesized and evaluated for their antimicrobial activity. The results showed that some compounds with a piperazine side chain exhibited comparable or better antibacterial activity than comparator cirprofloxacin. Furthermore, the targeted compounds also displayed a broad spectrum of activity against resistant strains including both Gram-negative and Gram-positive bacteria. In particular, compound 4h showed an MIC of 0.25 μg/mL in antibacterial assay against multiple drug-resistant Escherichia coli , which represents an about 30-fold increase of potency compared to ciprofloxacin. Thus, their excellent antibacterial activity against resistant strains suggests that triazole-fused fluoroquinolones warrant further optimization as novel anti-infective chemotherapies.

A series of cis-2,3-disubstituted cyclopropane 1,1-diesters were examined in the AlCl3-promoted [3 + 2]-annulations with aldehydes. In this reaction, these cis-cyclopropanes displayed reactivities starkly different from their trans counterparts in terms of the high chemical yields (up to 98%) and provided the desired annulation products with excellent diastereomeric purity. This protocol provides a facile and highly stereoselective way to construct synthetically useful pentasubstituted tetrahydrofurans not easily accessible using other methods.

Methyl butyrate (MB) has been investigated as a co-solvent for lithium-ion battery electrolytes to improve the performance at low temperature (−10 to −30 °C). The cycling performance of graphite/LiNi1/3Co1/3Mn1/3O2 cells with 1.2 M lithium tetrafluorooxalatophosphate (LiFOP) in 2:2:6 EC/EMC/MB was compared to 1.2 M LiPF6 in both 3:7 EC/EMC and 2:2:6 EC/EMC/MB. The LiFOP/MB electrolyte has a good operational temperature window and comparable cycling performance to the LiPF6 electrolyte at both room temperature and low temperature (−10 °C). However, after accelerated aging the LiFOP/MB electrolyte has worse performance at very low temperature (−30 °C) compared to LiPF6 electrolytes. Ex-situ surface analysis was conducted by scanning electron microscopy, X-ray photoelectron spectroscopy, and Fourier transfer infrared spectroscopy to provide insight into the performance differences.

A new triterpene saponin, ilexoside P (1), along with three known triterpene saponins, ilexoside O (2), ilexsaponin B3 (3) and ilexpublesnin A (4) was isolated from the roots of Ilex pubescens. Their chemical structures were elucidated on the basis of UV, IR, MS, and NMR spectroscopic analyses coupled with chemical degradation. In addition, the xanthine oxidase (XOD) inhibitory activity of the isolated saponins was reported. Compound 1 exhibited weak XOD inhibitory activity in the test.

The cycling performance of LiPF 4 (C 2 O 4 ) (LiFOP) electrolyte with propylene carbonate (PC) as a cosolvent is compared with LiPF 6 electrolyte with ethylene carbonate (EC) as a cosolvent in the presence of different cathode materials, such as LiNi 1/3 Co 1/3 Mn 1/3 O 2 and LiFePO 4 . The cycling performance of cells with LiFOP and PC is similar to cells with LiPF 6 with EC at room temperature and superior at low temperature (−10 °C). After thermal abuse the room temperature performance of cells with LiFOP electrolyte and PC is worse than cells with LiPF 6 and EC. A detailed analysis of the surface films on both the anode and the cathode via X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and Fourier transfer infrared spectroscopy (FT-IR) in the attenuated total reflection (ATR) mode was conducted to provide a better understanding of performance differences.

The reduction mechanism of ethylene sulfite (ES) in propylene carbonate (PC) based electrolyte is investigated using density functional theory in gas phase. Based on the electron affinity energy and lowest unoccupied molecular orbital (LUMO) energy, it can be known that free ES is reduced most easily compared with ES-Li + and ES-Li + -PC, generating SO 2 and propanal. However, the binding energy of ES-Li + and ES-Li + -PC is quite negative, indicating that both of them are more possible in electrolyte solution than the free ES. The reductive decomposition products of ES-Li + and ES-Li + -PC are OSO 2 Li, OSO 2 Li-R and ethylene. OSO 2 Li and OSO 2 Li-R are the main compositions of the solid electrolyte interphase film on the anode of lithium ion battery, which inhibits the reductive decomposition of PC. These calculations provide a detailed explanation on the experimental phenomena.

Lithium difluoro (oxalate) borate (LiDFOB) is used as thermal stabilizing and solid electrolyte interface (SEI) formation additive for lithium-ion battery. The enhancements of electrolyte thermal stability and the SEIs on graphite anode and LiFePO4 cathode with LiDFOB addition are investigated via a combination of electrochemical methods, nuclear magnetic resonance (NMR), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared-attenuated total reflectance (FTIR-ATR), as well as density functional theory (DFT). It is found that cells with electrolyte containing 5% LiDFOB have better capacity retention than cells without LiDFOB. This improved performance is ascribed to the assistance of LiDFOB in forming better SEIs on anode and cathode and also the enhancement of the thermal stability of the electrolyte. LiDFOB-decomposition products are identified experimentally on the surface of the anode and cathode and supported by theoretical calculations.

Polyethylene (PE)-supported poly(methyl methacrylate-vinyl acetate)-co-poly(ethylene glycol) diacrylate with and without doping nano-Al 2 O 3 , namely P(MMA-VAc)-co-PEGDA/PE and P(MMA-VAc)-co-PEGDA/Al 2 O 3 /PE, are prepared and their performances as gel polymer electrolytes (GPEs) for lithium ion battery are studied by mechanical test, scanning electron microscopy, thermogravimetric analyzer, electrochemical impedance spectroscopy, cyclic voltammetry, and charge/discharge test. It is found that the doping of nano-Al 2 O 3 in the P(MMA-VAc)-co-PEGDA/PE improves the comprehensive performances of the GPE and thus the rate performance and cyclic stability of the battery. With doping nano-Al 2 O 3 , the mechanical and thermal stability of the polymer and the ionic conductivity of the corresponding GPE increases slightly, while the battery exhibits better cyclic stability. The mechanical strength and the decomposition temperature of the polymer increase from 15.9 MPa to 16.2 MPa and from 410 °C to 420 °C, respectively. The ionic conductivity of the GPE is from 3.4 x 10 ―3 S cm ―1 to 3.8 x 10 ―3 S cm ―1 . The discharge capacity of the battery using the GPE with doping nano-Al 2 O 3 keeps 90.9% of its initial capacity after 100 cycles and shows good C-rate performance.

The insecticidal and repellent activities of essential oil from leaves ofEucalyptus grandisagainstCulex pipiens quinquefasciatuswere investigated. The essential oil was obtained by hydro-distillation and analyzed by gas chromatography-mass spectrometry (GC-MS). The principal constituents in the essential oil werep-cymene (26.794%),α-pinene (15.864%), eucalyptol (6.281%),α-terpineol (4.100%), limonene (3.614%) and borneol (2.519%). The results indicated that the essential oil ofEucalyptus grandisleaves hold insecticidal and repellent activities againstCulex pipiens quinquefasciatus. The complete protection time for people againstCulex pipiens quinquefasciatuswas correlative with its concentration. It could protect people for 7h when its concentration was 50%. Fumigating insecticidal activity was evaluated by airtight fumigation in conical flask. The LC50values of the essential oil for adults ofCulex pipiens quinquefasciatuswere 4.5%(0.5h), 3.6%(1h), 2.6%(2h), 2.1%(4h), 0.56%(8h) and 0.56%(24h). The LT50value of the essential oil was 19.1 min when its concentration was 6.4%.

A new gel polymer electrolyte (GPE) is reported in this paper. In this GPE, blending polymer of poly(ethylene oxide) (PEO) with poly(vinylidene fluoride-hexafluoropropylene) (P(VdF-HFP)), doped with nano-Al2O3 and supported by polypropylene (PP), is used as polymer matrix, namely PEO–P(VdF-HFP)–Al2O3/PP. The performances of the PEO–P(VdF-HFP)–Al2O3/PP membrane and the corresponding GPE are characterized with mechanical test, CA, EIS, TGA and charge–discharge test. It is found that the performances of the membrane and the GPE depend to a great extent on the content of doped nano-Al2O3. With doping 10 wt.% nano-Al2O3 in PEO–P(VdF-HFP), the mechanical strength from 9.3 MPa to 14.3 MPa, the porosity of the membrane increases from 42% to 49%, the electrolyte uptake from 176% to 273%, the thermal decomposition temperature from 225 °C to 355 °C, and the ionic conductivity of corresponding GPE is improved from 2.7 × 10−3 S cm−1 to 3.8 × 10−3 S cm−1. The lithium ion battery using this GPE exhibits good rate and cycle performances.

4,5-Dimethyl-[1,3]dioxol-2-one (DMDO) was used as a novel electrolyte additive for lithium-ion batteries. The effect of DMDO on the formation of the solid electrolyte interface (SEI) on anode and cathode of MCMB/LiNi0.8Co0.2O2 cells was investigated via a combination of electrochemical methods, X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) calculations. It is found that cells with electrolyte containing 2% DMDO have better capacity retention than cells without DMDO and this improved performance is ascribed to the assistance of DMDO in forming better SEIs on anode and cathode. DMDO-decomposition products are identified experimentally on the surface of the anode and cathode and supported by theoretical calculations.

Catalytic electrolysis of ammonia provides a promising technique for generation of hydrogen and, simultaneously, maintenance of environmental sustainability. In this work, the electro-oxidation of ammonia on platinum (Pt) electrode was systematically studied in alkaline solution by cyclic voltammetry. The effects of operating conditions and the electrochemical test parameters, such as ammonia concentration, KOH concentration, electrode rotating speed, temperature, upper switch potential, potential sweep rate and cyclic number, on the ammonia oxidation and hydrogen evolution were investigated. The ammonia oxidation on Pt electrode is controlled by mass-transfer process of ammonia towards the electrode surface. However, the adsorption and desorption of NxHy intermediates play important roles in ammonia oxidation and hydrogen evolution. Determination of the ammonia electro-oxidation kinetics depends on a comprehensive consideration of mass-transfer and adsorption/desorption processes. There is an optimal ammonia concentration and KOH concentration to maximize the ammonia oxidation and hydrogen evolution simultaneously. The ammonia electro-oxidation current decreases with the increasing electrode rotating speed, and increases with the elevated temperature. The cell efficiency for ammonia electrolysis on Pt electrode can be up to 45%. Increasing ammonia and KOH concentrations could increase the electrolytic cell efficiency slightly.

Electrosynthesis of glyoxylic acid by electroreduction of oxalic acid has long been well known. However, attempts to commercialize the process have encountered problems due to rapid deactivation of the cathode. The cathode activity can be continuously restored by adding small amounts of chemical activators to the catholyte. In this paper the structural effect of chemical activator on electrode reaction is studied. The results show that (1) It is the cation of the chemical activator, but not the anion that affects the current efficiency and the reaction selectivity. (2) The more symmetrical the cation, or the shorter the longest alkyl chain, the higher the current efficiency and the reaction selectivity become. (3) Mechanism of the activation is discussed. Adsorption of the cations of the activator on the cathode surface protects the electrode. (4) Quantitative characterization of the activator molecule is given using some topological indices, with which the activation ability can be predicted, and screening of the proper activator is made possible.

A facile and highly stereoselective synthesis to pentasubstituted tetrahydrofuran derivatives, which are not easily accessible by other methods, is presented.

In the title compound, C(20)H(22)O(8)S, the dihedral angle between the two benzene rings is 81.6 (3)°. The benzene-connected portions of the alk-oxy substituents are almost coplanar with their respective rings [C-C-O-C torsion angles of 174.77 (17) and -178.5 (4)°]. One of the butanoic acid groups is disordered over two conformations with a site-occupancy ratio 0.719 (6):0.281 (6). In the crystal, pairs of O-H⋯O hydrogen bonds link the mol-ecules into infinite zigzag chains along [130].

A novel nonflammable electrolyte for lithium-ion batteries has been developed. The optimized electrolyte is composed of LiPF 6 in a mixture of carbonate solvents with added dimethyl methylphosphonate as a flame retarding cosolvent and lithium bis(oxalatoborate) as an anode film forming additive. Conductivity, thermal stability, electrochemical stability, self extinguishing times, electrochemical cycling, and ex situ surface analysis of the cycled electrodes are reported. This novel electrolyte has a comparable cycling efficiency to the current state-of-the-art electrolytes for lithium-ion batteries but is nonflammable.