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Agonists selectively targeting cannabinoid receptor-like G-protein-coupled receptor (GPCR) GPR119 hold promise for treating metabolic disorders while avoiding unwanted side effects. Here we present the cryo-electron microscopy (cryo-EM) structures of the human GPR119-Gs signaling complexes bound to AR231453 and MBX-2982, two representative agonists reported for GPR119. The structures reveal a one-amino acid shift of the conserved proline residue of TM5 that forms an outward bulge, opening up a hydrophobic cavity between TM4 and TM5 at the middle of the membrane for its endogenous ligands-monounsaturated lipid metabolites. In addition, we observed a salt bridge between ICL1 of GPR119 and Gβs. Disruption of the salt bridge eliminates the cAMP production of GPR119, indicating an important role of Gβs in GPR119-mediated signaling. Our structures, together with mutagenesis studies, illustrate the conserved binding mode of the chemically different agonists, and provide insights into the conformational changes in receptor activation and G protein coupling.

The low-percolation-threshold conductive networking structure is indispensable for the high performance and functionalization of conductive polymer composites (CPCs). In this work, conductive carbon black (CCB)-reinforced ultrahigh-molecular-weight polyethylene (UHMWPE)/polypropylene (PP) blend with tunable electrical conductivity and good mechanical properties was prepared using a high-speed mechanical mixing method and a compression-molded process. An interconnecting segregated hybrid CCB-polymer network is formed in electrically conductive UHMWPE/PP/CCB (UPC) composites. The UPC composites possess a dense conductive pathway at a low percolation threshold of 0.48 phr. The composite with 3 phr CCB gives an electrical conductivity value of 1.67 × 10-3 S/cm, 12 orders of magnitude higher than that of the polymeric matrix, suggesting that CCB improves both the electrical conductivity and electromagnetic interference shielding effectiveness (EMI SE) of the composite at the loading fraction over its percolation threshold. The composite with 15 phr CCB presents an absorption-dominated electromagnetic interference shielding effectiveness (EMI SE) as high as 27.29 dB at the X-band. The composite also presents higher tribological properties, mechanical properties, and thermal stability compared to the UP blend. This effort provides a simple and effective way for the mass fabrication of CPC materials with excellent performance.

A simple, sensitive, and enantioselective HPLC-MS/MS method has been developed for the determination of orphenadrine (ORP) enantiomers in rat plasma for the first time. The method used diphenhydramine as the internal standard (IS), and plasma samples were extracted by liquid–liquid extraction with satisfactory recovery. Chiral separation of the ORP enantiomers was obtained on a Chiralcel OD-RH column (150 mm × 4.6 mm, 5 μm). The mobile phase consists of acetonitrile–ammonium bicarbonate buffer (30 mM, pH 9.0) (80 : 20, v/v). Sufficient resolution (Rs = 3.562) was achieved in a short analysis time (7 min). The multiple reaction monitoring (MRM) mode was used for the detection of ORP enantiomers and IS. The transitions of m/z 270.0 → 181.1 and 256.2 → 167.1 were chosen for monitoring the ORP enantiomers and IS, respectively. Linearity was confirmed in the range of 0.1–50.0 ng mL−1 with the lower limit of quantification of 0.1 ng mL−1 for both ORP enantiomers in plasma. After validation, the method was applied to the enantioselective pharmacokinetic study of ORP enantiomers in rat plasma following oral administration of 10 mg kg−1 racemic ORP. Significant differences (P < 0.05) of ORP enantiomers were observed in pharmacokinetic parameters including Cmax, AUC, t1/2, CL, Vd, MRT, and VRT, which indicated that enantioselective pharmacokinetic behavior of ORP enantiomers was present in rats.

Lithium metal anodes have attracted extensive attention due to their high theoretical capacity and low redox potential. However, low Coulombic efficiency, serious parasitic reaction, large volume change, and dendrite growth during cycling have hindered their practical application. The engineering of an anode current collector provides important advances to solve these problems, eliminate excess lithium usage, and substantially increase the energy density. In this review, we summarize the engineering strategies of an anode current collector with emphasis on different methods and applications in lithium metal-based systems. Finally, the perspectives and challenges of current collector engineering for lithium metal anode are discussed.

The isosteric replacement of C═C by B–N units in conjugated organic systems has recently attracted tremendous interest due to its desirable optical, electronic and sensory properties. Compared with BN-, NBN- and BNB-doped polycyclic aromatic hydrocarbons, NBN-embedded polymers are poised to expand the diversity and functionality of olefin polymers, but this new class of materials remain underexplored. Herein, a series of polymers with BNB-doped π-system as a pendant group were synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization from NBN-containing vinyl monomers, which was prepared via intermolecular dehydration reaction between boronic acid and diamine moieties in one pot. Poly{2-(4-Vinylphenyl)-2,3-dihydro-1H-naphtho[1,8-de][1,3,2]diazaborinine} (P1), poly{N-(4-(1H-naphtho[1,8-de][1,3,2]diazaborinin-2(3H)-yl)phenyl)acrylamide} (P2) and poly{N-(4-(1H-benzo[d][1,3,2]diazaborol-2(3H)-yl)phenyl)acrylamide} (P3) were successfully synthesized. Their structure, photophysical properties and application in metal ion detection were investigated. Three polymers exhibit obvious solvatochromic fluorescence. As fluorescent sensors for the detection of Fe3+ and Cr3+, P1 and P2 show excellent selectivity and sensitivity. The limit of detection (LOD) achieved by Fe3+ is 7.30 nM, and the LOD achieved by Cr3+ is 14.69 nM, which indicates the great potential of these NBN-embedded polymers as metal fluorescence sensors.

Rational construction of high-efficient and low-cost catalyst is one of the most promising ways to produce liberally hydrogen but almost remains a huge dare. Hence, a novel work by the interface engineering and hetero-atom doping to synthesize V doped sulfide/phosphide heterostructure grown on nickel foam (V-Ni 3 S 2 /Ni x P y /NF) is proposed via a phosphating treatment at low temperature. The incorporation of V can adjust the electronic structures of Ni 3 S 2 , optimize electronic transmission, expose more active sites and protect the 3D structure of Ni foam. Meanwhile, the excellent conductivity of NF and the abundant interstices between nanosheets have a positive effort for HER. As a result, the V-Ni 3 S 2 /Ni x P y /NF (VNSP/NF) nanosheets catalyst exhibits the outstanding HER activity with an extremely low overpotential of 90 mV at the current density of 10 mA cm -2 for HER and stable durability in alkaline solution, which exceeds most of the previously reported about Ni-based materials. This work proves the rational design of the interfacial engineering and metal atom incorporation have a significant influence for efficient hydrogen evolution.

Herein, we report the construction of a rose-shaped cobalt phenylphosphonate coordination polymer [Co(PhPO3)] via the solvothermal method, which has been used as a precursor to prepare porous Co2P2O7/C nanohybrid through a thermal transformation process in N2. By controlling the calcination temperature, a series of polyporous rose-shaped Co2P2O7/C-X (X = 600, 700, 800, 900 and 1000) have been successfully obtained. The prepared Co2P2O7/C-X materials present in situ hybrid nanostructures and a unique polyporous structure, which will provide rich electrochemical active centers and enough migration paths for electrons and electrolyte for fast and deep faradaic reactions. As a supercapacitor electrode, the optimized Co2P2O7/C-900 demonstrated a specific capacitance of 349.6 F g−1 at 1 A g−1 and remarkable cycling performances (97.33% retention after 3000 cycles at 2 A g−1). Moreover, using the porous rose-shaped Co2P2O7/C-900 as a cathode with 3D porous graphene gel (3DPG) as an anode, an asymmetric supercapacitor Co2P2O7/C-900//3DPG was fabricated. The device showed an energy density of 21.9 W h kg−1 at a power density of 0.375 kW kg−1 and outstanding cycle stability of maintaining 106.25% initial capacity after 10 000 cycles at 3 A g−1.

The enantiomeric separation of seven imidazole antifungals was first systematically examined on a derivative polysaccharide chiral stationary phase (CSP), i.e. Chiralcel OD-RH in the reversed phase mode. The influence of the type and content of the organic modifier, the pH of buffer solution, type and concentration of buffer salt, and column temperature on enantiomeric separation were evaluated and optimized. The maximum resolution values for flutrimazole, econazole, miconazole, butoconazole, isoconazole, sulconazole, and climbazole were 2.36, 1.55, 0.89, 1.51, 0.96, 1.13, and 2.30. For a better understanding of the chiral recognition mechanism, detailed computational simulations of Chiralcel OD-RH interaction with seven pairs of enantiomers were carried out using the molecular docking software AutoDock. The various interactions affecting enantiomeric separation were confirmed in detail from the the molecular level. The modeling data were in agreement with the chromatographic results concerning enantioselectivity. It was found that the enantiomeric separation of imidazole analytes on Chiralcel OD-RH was the result of a mixture of hydrogen bonds, π–π, hydrophobic, dipole–dipole, and some special interactions. The docking results showed good agreement with our experimental results.

In this study, carboxymethyl-6-(4-methoxybenzylamino)-β-cyclodextrin (CMCDPN) was synthesized for the first time and managed to be used as a chiral selector to enantioseparate 13 kinds of chiral drugs (chlorpheniramine, brompheniramine, pheniramine, homatropine, homatropine methyl, clorprenaline, terbutaline, procaterol, tulobuterol, cycloclenbuterol, propranolol, pindolol and ofloxacin) by capillary electrophoresis (CE). The analysis was carried out by CE using a fused-silica capillary (50 cm × 50 μm i.d., 40 cm effective length) with 30 mmol L−1 phosphate buffer under an applied voltage of 20 kV. The effect of analysis conditions such as buffer concentration, buffer pH, applied voltage and concentration of the chiral selector on the enantioseparation results was systematically investigated. By the method established by us, eleven of the analytes reached baseline separation and the other two reached partial separation. The molecular dockings were applied to further demonstrate the mechanisms of chiral recognition. The docking results showed good agreement with our experimental results.

The catalytic properties of non-noble metal catalysts are not comparable to those of noble metal catalysts, such as Pt and Ru, on account of the catalytic thresholds of these non-noble metal catalysts. In order to solve this problem, an efficient P, W-MoS2/NiSP/NF catalyst was rationally designed through heteroatom (P and W) doping and heterostructure construction. Interestingly, motivated by the synergistic incorporation of W and P, the 2H-phase MoS2 with limited edge active sites was partially converted into highly active 1T-phase MoS2 with rich defects, which basically activate the hydrogen evolution reaction (HER)-inert basal plane of MoS2 and significantly enlarge the number of active sites, ultimately endowing the well-designed P, W-MoS2/NiSP/NF catalyst with Pt-like HER performance and superior oxygen evolution reaction (OER) performance. Importantly, this work exerts a profound influence on the construction of 1T-MoS2 with defects, the design of multi-stage structures, and the achievement of Pt-like catalytic performance.

The development of highly efficient photocatalysts is vital for solvinge the problem of environmental pollution. In this study, a novel zero-/two-dimensional (0D/2D) S-scheme heterojunction was fabricated by integrating 0D copper phosphide (Cu

Hydrogen evolution reaction (HER) via electrocatalysis using cost-efficient bimetallic phosphide as electrocatalyst holds a great promise for environmentally friendly energy technologies. Here we report a novel strategy to synthesize a series of CoNiP multi-shelled hollow microspheres with different ratios of Co to Ni using metal–organic framework as both the precursor and the template, and the as-obtained CoNiP-0.25 presents a pre-eminent electrocatalytic activity for the hydrogen evolution reaction (HER) in 1.0 M KOH. The CoNiP-0.25 microspheres are found to drive 20 mA cm−2 at a potential of 170 mV vs. RHE, which is 120 mV and 59 mV smaller than that of pure NiP and CoP, respectively. The outstanding HER activity of the CoNiP-0.25 microspheres can be attributed to the optimization of their electronic structure, the typical multi-shelled hollow structure and the massive exposure of the active phase bimetallic phosphide CoNiP. Moreover, the enhanced electrochemical stability of CoNiP electrocatalyst might also stem from its special structure of multi-shelled hollow microsphere, which inhibits its superficial oxidation during the catalytic process.

Transition metal carbonitrides play an important role in high-temperature structural ceramics, high-temperature coatings and alloy reinforcements. In this paper, we have searched for more than a dozen compounds of the type MxCyNz, with the special focus on M2CN compounds. The electronic structure and mechanical properties of transition-metal carbonitrides M2CN (M = V, Ti, Ta, Nb, Hf and Zr) are investigated by the first-principle calculations based on the density functional theory. The stability of ternary compounds M2CN is evaluated by calculating cohesive energy, formation energy and phonon dispersion spectrum. Electronic structures and chemical bonding characteristics are analyzed by the density of states and Mulliken population analysis. The mechanical properties, such as bulk, shear, Young's modulus, hardness and Poisson’s ratio, are obtained, the modulus of M2CN is generally higher than that of other carbonitrides. The anisotropic mechanical properties of M2CN are interpreted, anisotropic index and three-dimensional surface contours show that Ti2CN has the weakest elastic anisotropy. The simple mixed values HM, BM, GM and EM are calculated and are compared with the earlier calculated and experimental values.

Commercial graphite, as an attractive cathode material, has been extensively applied in rechargeable aluminum batteries. However, low capacity and complex cathode preparation procedures limit its further development. Herein, graphite nanosheets as cathode of aluminum battery have been prepared by a novel pencil-drawing strategy, which shows superior capacity of 96 mAh g

The traditional oxygen reduction/evolution reaction (ORR/OER) catalysts are mainly noble metal-based materials, but their scarcity and instability impede their practical applications, especially in Zn–air batteries. Hence, identifying a bifunctional catalyst with low-cost and high-stability is very crucial for Zn–air batteries. Herein, we report a simple method to prepare core–shell-structured Co@Co3O4 nanoparticles encapsulated into N-doped carbon polyhedra by carbonization and controlled oxidation of metal–organic frameworks (MOFs), which are then applied as a bifunctional catalyst for Zn–air batteries. Using such a configuration, enhanced performances, including a high power density of ∼64 mW cm−2, a stable voltage profile over 80 h battery operation with four mechanical recharges, a small discharge/charge overpotential of ∼0.66 V and a long-life of 100 cycles for 200 h operation at 5 mA cm−2, have been achieved. These excellent performances can be attributed to abundant graphited carbon and CNTs, high N-doping, plentiful pores, the synergy between the semiconductive Co3O4-coating layer and the conductive Co bulk, and the uniform Co@Co3O4 nanoparticles in this catalyst which effectively improve electrical conductivity/ion transfer and further concertedly promote the catalytic activity towards the ORR/OER. Moreover, the belt-shaped polymer Zn–air battery with this catalyst also shows good electrochemical stability under different deformations.

The metal organic framework derived materials (CoFe2O4@NC) activated peroxymonosulfate (PMS) to degrade Norfloxacin (NOR) owing to the characteristics of high surface area (109.658 m2 g−1) and abundant mesoporous structure. The characterization results demonstrated that the optimal ratio of bimetal and of bimetallic to organic ligands (M/O) had good crystal structure and stability (Fe/Co = 3:1, M/O = 2:1). Moreover, NOR (10 mg L−1) removal of 98.78% was achievable in 60 min with an optimum concentration of PMS (0.32 mM) and dosage of CoFe2O4@NC (0.1 g L−1). The radical quenching results suggested that SO4·-, ·OH and 1O2 functioned in the presence of the system certificated by XPS spectra. The presence of Cl− and CO32−/HCO3− promoted the catalyst reaction. The recoverability revealed high removal efficiency of NOR of 93.55% could still be maintained. Furthermore, four pathways of NOR degradation were proposed, including dehydroxylation, defluorination, quinolone group conversion and piperazine ring transformation, which were attributed to the synergy of reactive oxygen species. The above results highlight that the method is of great significance to the practical application of heterogeneous catalysts in aqueous solutions.

Two novel inorganic–organic hybrid zinc phosphites, namely, [Zn(1,2-bimb)0.5(HPO3)]n (1) and [Zn(1,4-bmimb)0.5(HPO3)]n (2), (1,2-bimb = 1,2-bis(imidazol-1ylmethyl)benzene; 1,4-bmimb = 1,4-bis((2-methyl-1H-imidazol-1yl)methyl)benzene) were synthesized for the first time by hydrothermal reaction. Compound 1 generates a three-dimensional (3D) pillared-layer structure with a 2-nodal 3,4-connected 3,4T15 topology. While compound 2 exhibits a 2D hybrid zinc phosphite sheet with a 3,4-connected 3,4L83 topology network. Utilizing compound 1 and compound 2 as templates and Na2S as an etching agent, a series of highly efficient ZnO/ZnS photocatalysts were obtained. The optimized 1-160 sample demonstrates the highest evolution rate of 22.6 mmol g−1 h−1, exceeding the rate of commercial ZnS samples by more than 14.5 times. The remarkable photocatalytic activity should be attributed to the unique heterojunction structure which shortens the free path of charge carriers and enhances the charge separation efficiency. This work provides a facile strategy for preparing photocatalysts with efficient photocatalytic hydrogen production derived from inorganic–organic hybrid material.

SnS2 has aroused great interests for application of sodium-ion batteries, because of its graphene-like structure and high theoretical capacity. Herein, we present an effective nanocasting strategy to fabricate the SnS2/enteromorpha prolifera derived carbon (SnS2/EPC) composite, whose microstructure anchors the SnS2 nanosheets on enteromorpha prolifera (EP) derived carbon. It can effectively solve the problems of poor conductivity and volume expansion of SnS2 electrode during charging and discharging process. The optimized SnS2/EPC could deliver high reversible capacity of 443 mA h g−1 at 0.1 A g−1, and maintain reversible capacity of 340 mA h g−1 at high rate of 2 A g−1 after 450 cycles, indicating that SnS2/EPC is a promising anode material for sodium storage.

The transition metal phosphate with lower price and rich abundance have a tendency to replace Pt-based catalytic materials for hydrogen evolution reaction (HER). Nevertheless, for transition metal phosphate based electrocatalyst, the further improvement of the electrocatalytic performance and the deep exploration of the regulation and control mechanism are still bottleneck problems. At present, we use a novel method to prepare the Ti foil supported the CoP acacia-like arrays decorated with RuP4 nanoparticles composite (RuP4@CoP/Ti). The obtained RuP4@CoP/Ti possesses excellent electrocatalytic performance, which needs the overpotential of 66.2 mV to reach the current of density of 10 mA cm−2 and has the Tafel slope of 52.6 mV dec−1 in 0.5 M H2SO4. In addition, it requires the overpotential of 36 mV to reach the current of density of 10 mA cm−2 and has Tafel slope of 54.8 mV dec−1 in 1 M KOH. Moreover, the obtained RuP4@CoP/Ti also presents outstanding long-term durability under either acidic or alkaline condition. The reason for such excellent properties is due to the unique acacia-like structure, the synergistic effect between CoP and RuP4, the existence of Ti foil and the introduction of Ru, which can optimize the electronic structure of Co and P.

Ni Mo/diamond composite coatings were electrodeposited on stainless steel from a plating bath containing micron-sized diamond particles. Effects of electrodeposition parameters on the composition, microstructure, mechanical properties and corrosion resistance are studied. Results show that the chemical composition of coatings strongly depends on the selection of electrodeposition parameters. The Ni Mo matrix of coatings consisted of Ni(Mo) solid solution with ultrafine nanograins. The hardness of coatings was enhanced by adding diamonds and annealing treatment, and the highest hardness was about 11.3 GPa. Meanwhile, the wear rate of composite coatings was at least about 1/6 of that for Ni Mo coating. Furthermore, the corrosion resistance of coatings in 3.5 wt% NaCl solution was slightly decreased due to the micro-galvanic cells between the matrix and diamonds.

Correction for ‘In situ encapsulation of core–shell-structured Co@Co3O4 into nitrogen-doped carbon polyhedra as a bifunctional catalyst for rechargeable Zn–air batteries’ by Ziyang Guo et al., J. Mater. Chem. A, 2018, 6, 1443–1453, DOI: 10.1039/C7TA09958D.

Monodispersed nickel phosphide nanocrystals (NCs) with different phases (Ni12P5, Ni2P and Ni5P4) were synthesized via the thermal decomposition approach using nickel acetylacetonate as the nickel source, trioctylphosphine as the phosphorus source and oleylamine in 1-octadecene as the reductant. The phases of the as-synthesized nickel phosphide NCs could easily be controlled by changing the P : Ni precursor ratio. The structure and morphology of the as-synthesized nickel phosphide NCs were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDX), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR) and N2 adsorption–desorption. A formation mechanism for the as-synthesized nickel phosphide NCs was proposed. We further studied the influence of the phase of the nickel phosphide NCs on the electrocatalytic properties for the hydrogen evolution reaction (HER). All phases showed good catalytic properties, and the Ni5P4 NCs with a solid structure exhibited higher catalytic activity than the Ni12P5 and Ni2P NCs. This superior catalytic activity is attributed to the higher positive charge of Ni and a stronger ensemble effect of P in Ni5P4 NCs. This study demonstrates that the crystalline phase is important for affecting the electrocatalytic properties.

Ti6Al4V substrates were multiply modified to create a surface with improved biocompatibility and functional properties. The multi-modifications of Ti6Al4V alloy involve depositing diamond-like carbon (DLC) on it as a bio-mechanical coating and then grafting 1H,1H,2H,2H-perfluorodecyl acrylate on DLC from neat liquids upon irradiation at 254 nm to form a dense monolayer. The as-fabricated multilayer films were characterized using X-ray photoelectron spectroscopy (XPS), contact angle meter (CA), and 3D surface profiler. Results show that the bifunctional alkenes are successfully photochemically grafted to DLC-coated Ti6Al4V and the multi-modifications evidently reduce both the surface energy and roughness. By in vitro cytotoxicity test with MC3T3-E1 osteoblasts, the as-fabricated films exhibit admirable cytocompatibility. The longtime soaked films also display the behavior for excellent anticorrosion and friction in the simulated body fluid (SBF) environment. All results suggest that the biocompatibility and functional properties of the multiply modified Ti6Al4V substrates have been continuously adapted to a desired value. Owing to the DLC which can be deposited on most substrate materials and the probable application extension of photochemical grafting to wide range, we envisage that this method will provide a potential and effective approach for the surface modification of DLC coated and other implant biomaterials.