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0D metal halides composed of TBA+ cations and anions with different inorganic frameworks possess different emission centres under UV light excitation.

With recent outbreaks of fatal strains of diseases and the emergency of antibiotic resistance, there is a pressing demand to discover bactericidal materials that can effectively reduce or prevent infections by pathogenic bacteria. Herein, silver(I) metal organic frameworks Ag

The mixture of TBAX powder and PbX2 powder were heated and then naturally cooled to form DES-TBAX/PbX2 for the first time, and 1D(TBA)4Pb5Br14−xClx·HBr(Cl)·2H2O and TBAPbI3 perovskites were formed in the DES-TBAX/PbX2 with good thermal stability.

Laser irradiation is used to induce CsPbBr3 NPLs reshaping and morphology control. A hierarchical self-assembly process occurs in the CsPbBr3 NPLs. The crystal growth relies on seeking dynamic balance between heat dissipation and accumulation.

A cheap and easily available ZnEt2 is an effective precatalyst, which can be used for the hydroboration reaction of various organic carbonates and esters with HBpin.

A new type of Pd@mSiO2 composite nanospheres with controlled pore structure, consisting of internal Pd cores and controlled mesoporous silica shells, has been prepared by a facile one-pot method. The thickness and pore size of the shell could be easily tuned by changing the amounts of TEOS and the hydrophobic block length, respectively, during synthesis. In this perspective, the effects of CTAB concentration, pH, and TEOS concentration on the monodisperse sphere morphology of Pd@mSiO2 nanoparticles (NPs) were investigated. In addition, a nucleation mechanism was proposed. Hydrogenation of nitrobenzene to aniline was used as a model reaction to discuss the effect of pore size on the transport rate of the reactants and the product selectivity in metal-catalyzed hydrogenation. The catalysts exhibited a high conversion rate and significantly enhanced stability, leading to a higher recyclability without loss of catalytic activity compared to conventional supported catalysts and commercial catalysts.

Mixed silicon and carbon (Si–C) materials with high capacity are ideal candidates for the substitution of graphite or other carbon anodes in lithium-ion batteries. However, the low coulombic efficiency of the Si–C anode in the first cycle due to the formation of a solid electrolyte interphase and the consumption of active lithium have hindered its commercial applications. Here, we report using Li2S as a prelithiation material to compensate for the loss of active lithium in the first cycle and, consequently, to enhance the specific energy of lithium-ion batteries. The Si–C anode has an initial discharge specific capacity of ∼738 mA h g−1 and a charge specific capacity of ∼638 mA h g−1. The prelithiation material with a core–shell structure is prepared by mixing Li2S, Ketjenblack (KB) and poly(vinylpyrrolidone) (PVP) in anhydrous ethanol, which shows a high irreversible capacity of ∼1084 mA h g−1. The effect of the compensation of lost active lithium is verified via a LiFePO4 (Li2S)/Si–C full cell, which exhibits not only a high specific capacity but also a stable cycling performance. The specific energy of the LiFePO4 (Li2S)/Si–C full cell shows a remarkable increase compared to the LiFePO4/Si–C full cell, exhibiting ∼13.4%, ∼26.7%, ∼65.0% and ∼110.2% more specific energy after the 1st, 10th, 100th and 200th cycle, respectively.

The alkylation reaction of isobutane with 2-butene to yield C8-alkylates was performed using Bronsted–Lewis acidic ionic liquids (ILs) comprising various metal chlorides (ZnCl2, FeCl2, FeCl3, CuCl2, CuCl, and AlCl3) on the anion. IL 1-(3-sulfonic acid)-propyl-3-methylimidazolium chlorozincinate [HO3S-(CH2)3-mim]Cl-ZnCl2 (x=0.67) exhibited outstanding catalytic performance, which is attributed to the appropriate acidity, the synergistic effect originating from its double acidic sites and the promoting effect of water on the formation and transfer of protons. The Lewis acidic strength of IL played an important role in improving IL catalytic performance. A 100% conversion of 2-butene with 85.8% selectivity for C8-alkylate was obtained under mild reaction conditions. The IL reusability was good because its alkyl sulfonic acid group being tethered covalently, its anion [Zn2Cl5]− inertia to the active hydrogen, and its insolubility in the product. IL [HO3S-(CH2)3-mim]Cl-ZnCl2 had potential applicability in the benzene alkylation reaction with olefins and halohydrocarbons.

The formation of Li dendrites is effectively inhibited by utilizing a small amount of polysulfide (1 to 2 mM Li2Sx, 2 ≤ x ≤ 8) in a conventional carbonate electrolyte to introduce a significant amount of polyethylene oxide (PEO)-like polymers into solid-electrolyte interphase (SEI) films. The polysulfide added likely acts as a catalyst rather than an additive, which is not consumed during repeated charging/discharging cycles. Thus the stability of Li-metal batteries during prolonged cycling is remarkably improved.

Detailed investigation of the influence of surface modification using a typical oxide (TiO2) on the electrochemical cycling performance of LiNi0.5Mn1.5O4 at room temperature (25 °C) and elevated temperature (55 °C) is reported. This spinel cathode material is commonly surface-modified with various metal oxides to improve its electrochemical cycling performance in lithium ion batteries. However, the underlying mechanisms of such a treatment, with respect to the surface crystal structure and chemistry evolution, have remained unclear. Bare-LiNi0.5Mn1.5O4 and TiO2-modified LiNi0.5Mn1.5O4 both show excellent cycling performance, i.e. almost no capacity retention and ∼99% coulombic efficiency for 150 cycles, at room temperature. However, at 55 °C the latter shows significantly better electrochemical cycling performance, with 93% capacity retention and ∼96% coulombic efficiency for 100 cycles, than the former with 70% capacity retention and ∼93% coulombic efficiency. Via advanced electron microscopy techniques, we observed that titanium ions migrated into the surface region of LiNi0.5Mn1.5O4 during the surface modification process at high temperature and reconstructed the (1–3 nm) surface spinel structure into a rocksalt-like structure and the subsurface (several nanometers) into a pseudo-rocksalt-like structure. The reconstruction of the surface and subsurface of the LiNi0.5Mn1.5O4 spinel cathode material mitigates not only the migration of Mn ions from the bulk into the electrolyte but also the formation of a solid state electrolyte interface, which plays a critical role in the improvement of electrochemical cycling performance at elevated temperatures.

Low-temperature, solution-processed perovskite solar cells (PSCs), which utilized organic poly[4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]-thiophenediyl] (PTB7) as a hole-transport layer (HTL), achieved a power conversion efficiency (PCE) as high as 13.29% when fabricated in ambient air. Through a comparative study, we demonstrate this PCE value to be superior compared to its counterparts with spiro-OMeTAD or P3HT as the HTL; the superiority consists of a higher fill factor (FF) and open-circuit voltage (Voc). By probing the absorption spectrum of CH3NH3PbI3−xClx before and after spin-coating the PTB7, it is discovered that the spin coating of PTB7 has little influence on the quality of the perovskite films. Furthermore, it is shown that PTB7 possesses higher conductivity compared with conventional HTLs, including spiro-OMeTAD, P3HT and PCDTBT. Moreover, in order to further improve device performance, the prevalent additives lithium bis (trifluoromethylsulphony) imide (LiTFSI) and 4-tert-butylpyridine (t-Bp) are investigated, along with a post-annealing process that is applied to the whole device. The results presented here and the overall fabrication method represent a helpful new approach for fabricating highly efficient perovskite-based photovoltaic devices.

Nanostructured MoS2 is very promising as an electrocatalyst for hydrogen evolution due to a greater number of active edge sites. However, a very large resistance between basal planes decreases the overall efficiency of hydrogen evolution, and greatly limits its application in industry. Herein we develop a facile strategy to synergistically increase the number of active edge sites and the conductivity of MoS2. MoS2 nanosheet arrays can be grown vertically on a carbon fiber cloth (CFC) substrates by a facile strategy. On the one hand, ammonium fluoride in the reaction system could effectively etch the inert basal plane of the MoS2 nanosheets, leading to the formation of pits in the inert basal plane of the MoS2 nanosheets. Thereby the number of active edge sites is significantly increased. On the other hand, the vertical growth of MoS2 nanosheet arrays on CFCs can significantly decrease the resistance of MoS2-based electrocatalysts. As a result, the MoS2-based electrocatalysts exhibit excellent catalytic activity for hydrogen evolution reactions, with a small Tafel slope and a large cathodic current density. Moreover, the CFC can be repeatedly utilized as a template to grow ultrathin MoS2 nanosheet arrays for HERs. The excellent activity and recyclable utilization, as well as mass production, indicate that the composite has promising applications in industry.

Flexible lithium-ion batteries are the key to powering a new generation of flexible electronics such as roll-up displays, smart electronics, and wearable devices. Here we report, for the first time, one-step hydrothermal synthesis of a three-dimensional (3D) hierarchical MoS2 nanoflake array/carbon cloth which shows potential for improving the performance of flexible lithium-ion batteries. Structural characterizations show that the 3D hierarchical MoS2 nanoflake array/carbon cloth has a similar ordered woven structure to the bare carbon cloth. Each carbon microfiber is covered with many highly ordered 3D MoS2 nanoflake arrays, and a typical MoS2 nanoflake, with expanded spacing of the (002) crystal plane, has a uniform width of about 400 nm and a thickness of less than 15 nm. The flexible 3D MoS2 nanoflake array/carbon cloth as a flexible lithium-ion battery anode has a high reversible capacity of 3.0–3.5 mA h cm−2 at a current density of 0.15 mA cm−2 and outstanding discharging/charging rate stability. Moreover, a fabricated full battery, with commercial LiCoO2 powder and the hierarchical architectures as electrodes, exhibits high flexibility and good electrochemical performance, and can light a commercial red LED even after 50 cycles of bending the full battery.

MoS2 nanoflake array films on different glass substrates were fabricated by an in situ growth method. The nonlinear absorption (NLA) properties of the MoS2 nanoflake array films were investigated by an open-aperture Z-scan technique. The MoS2 nanoflake array films exhibited different NLA properties dependent on the input energy. In the case of lower input energy, the films exhibited saturable absorption (SA); however, if the input energy was increased, a changeover from SA to reverse saturable absorption (RSA) was observed. The interesting NLA properties of the films could be attributed to the competition between the ground-state absorption and the excited-state absorption in terms of the energy-level model of MoS2.

In the paper, we find that graphene has a strong dielectric loss, but exhibits very weak attenuation properties to electromagnetic waves due to its high conductivity. As polyaniline nanorods are perpendicularly grown on the surface of graphene by an in situ polymerization process, the electromagnetic absorption properties of the nanocomposite are significantly enhanced. The maximum reflection loss reaches −45.1 dB with a thickness of the absorber of only 2.5 mm. Theoretical simulation in terms of the Cole–Cole dispersion law shows that the Debye relaxation processes in graphene/polyaniline nanorod arrays are improved compared to polyaniline nanorods. The enhanced electromagnetic absorption properties are attributed to the unique structural characteristics and the charge transfer between graphene and polyaniline nanorods. Our results demonstrate that the deposition of other dielectric nanostructures on the surface of graphene sheets is an efficient way to fabricate lightweight materials for strong electromagnetic wave absorbents.

The micelle structure of octenyl succinic anhydride modified ε-polylysine (M-EPL), an anti-microbial surfactant prepared from natural peptide ε-polylysine in aqueous solution has been studied using synchrotron small-angle X-ray scattering (SAXS). Our results revealed that M-EPLs formed spherical micelles with individual size of 24–26 Å in aqueous solution which could further aggregate to form a larger dimension with averaged radius of 268–308 Å. Furthermore, M-EPL micelle was able to encapsulate curcuminoids, a group of poorly-soluble bioactive compounds from turmeric with poor oral bioavailability, and improve their water solubility. Three loading methods, including solvent evaporation, dialysis, and high-speed homogenization were compared. The results indicated that the dialysis method generated the highest loading capacity and curcuminoids water solubility. The micelle encapsulation was confirmed as there were no free curcuminoid crystals detected in the differential scanning calorimetry analysis. It was also demonstrated that M-EPL encapsulation stabilized curcuminoids against hydrolysis at pH 7.4 and the encapsulated curcuminoids showed elevated cellular antioxidant activity compared with free curcuminoids. This work suggested that M-EPL could be used as new biopolymer micelles for delivering poorly soluble drugs/phytochemicals and improving their bioactivities.