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Combination of these strategies ultimately will lead us closer to the large-scale application of LMBs which often is called the "Holy Grail" of energy storage systems.Dioxygen (O2) activation is a vital step in many oxidation reactions, and a graphitic carbon nitride (g-C3N4) sheet is known as a famous semiconductor catalytic material. Here, we report that the atomic boron (B)-doped g-C3N4 (B/g-C3N4) can be used as a highly efficient catalyst for O2 activation. Our first-principles results show that O2 can be easily chemisorbed at the B site and thus can be highly activated, featured by an elongated O-O bond (∼1.52 Å). Interestingly, the O-O cleavage is almost barrier free at room temperatures, independent of the doping concentration. It is revealed that the B atom can induce considerable spin polarization on B/g-C3N4, which accounts for O2 activation. The doping concentration determines the coupling configuration of net-spin and thus the magnitude of the magnetism. However, the distribution of net-spin at the active site is independent of the doping concentration, giving rise to the doping concentration-independent catalytic capacity. The unique monolayer geometry and the existing multiple active sites may facilitate the adsorption and activation of O2 from two sides, and the newly generated surface oxygen-containing groups can catalyze the oxidation coupling of methane to ethane. The present findings pave a new way to design g-C3N4-based metal-free catalysts for oxidation reactions.Luminescent liquid crystals (LLCs) attract considerable attention because of their broad applications in displays, chemosensors, and anti-counterfeiting. However, it remains challenging to achieve a high luminescence efficiency in LCs because of the common aggregation-caused quenching effect. Herein, we demonstrate a facile approach to designing LLCs with a high quantum yield up to 88% by deliberately tuning the aggregation behavior of platinum(II) complexes with alkoxy chains (C n H2n+1O-). LLCs in hexagonal columnar and rectangular columnar phases are achieved when n = 12 and 16, respectively, as revealed by one-dimensional wide-angle X-ray diffraction and small-angle X-ray scattering. These LLCs are able to not only exhibit strong emission at elevated temperatures but also show attractive reversible vapochromism upon alternative CH2Cl2 and EtOH fuming, which imparts added functions and promises technological utility.The superhydrophilic/underwater superoleophobic membrane materials have attracted considerable attention in oil/water separation. However, most materials are extremely susceptible to pollution during oil-water separation, which drastically restricts their widespread applications. Herein, a momordica-charantia-like nanofibrous membrane (MCNM) with underwater superoleophobic performance was fabricated through a sacrifice template strategy by the electrospinning solution of zeolitic imidazolate framework-8 (ZIF-8) and polyacrylonitrile particles. The opened voids and wrinkles left after removing the template of nanocrystals ZIF-8 not only increased the porosity and roughness of the as-prepared fibrous membrane but also tremendously improved the underwater superoleophobicity. Therefore, the as-prepared MCNM showed excellent self-cleaning performance toward crude oil under water, avoiding the decrease of the separation efficiency and flux caused by membrane fouling during oil-water separation. [https://www.selleckchem.com/products/PHA-793887.html selleck chemicals] Meanwhile, the separation efficiency of various surfactant-stabilized oil-in-water emulsions was higher than 99.6% with a flux up to 1580 ± 30 L m-2 h-1 solely driven by gravity. Moreover, no obvious wrinkles and cracks were observed on the resulted nanofibrous membrane after the sand impact and bent testing. More importantly, the as-prepared MCNM still maintained exceptional underwater superoleophobicity in harsh environment (3.5 wt % NaCl, 4 M HCl, 50 °C hot water) even after ultrasound for 1 h. The robust mechanical and chemical stability makes the antifouling MCNM exhibit tremendous potential for practical applications in dealing with oily wastewater in the future.BiSbTeSe2 is a 3D topological insulator (3D-TI) with Dirac type surface states and low bulk carrier density, as donors and acceptors compensate each other. Dominating low-temperature surface transport in this material is heralded by Shubnikov-de Haas oscillations and the quantum Hall effect. Here, we experimentally probe and model the electronic density of states (DOS) in thin layers of BiSbTeSe2 by capacitance experiments both without and in quantizing magnetic fields. By probing the lowest Landau levels, we show that a large fraction of the electrons filled via field effect into the system ends up in (localized) bulk states and appears as a background DOS. The surprisingly strong temperature dependence of such background DOS can be traced back to Coulomb interactions. Our results point at the coexistence and intimate coupling of Dirac surface states with a bulk many-body phase (a Coulomb glass) in 3D-TIs.Herein, we report a new photochemical method for C(sp3)-H chlorination of amides which employs tert-butyl hypochlorite as the chlorinating agent and a household compact fluorescent lamp as the light source. The reaction proceeds via N-heterocyclic carbene SIPr·HCl-promoted N-H chlorination and subsequent photoinduced Hofmann-Löffler-Freytag chlorine atom transfer. The latter process is facilitated by (diacetoxyiodo)benzene. This protocol exhibits a broad scope and is suitable for site-selective chlorination of methyl hydrogen as well as methylene and methine hydrogen.This paper reports a highly site-selective alkylation of heteroarene N-oxides using hypervalent iodine(III) carboxylates to serve as an alkylating agent in the presence of a cheap copper catalyst under visible light conditions. This mild method proceeds at room temperature in an air atmosphere and can withstand various heteroarene N-oxides as well as various primary, secondary, and tertiary alkyl carboxylic acids. It also provides a practical method for enabling the rapid conversion of commercially available raw materials into medically relevant "drug-like" molecules.