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C/Ti3C2/g-C3N4 hollow microspheres (HM) were prepared by the template method to construct Ti3C2/g-C3N4 Schottky junctions on the spherical surface. The C/Ti3C2/g-C3N4 HM Schottky junctions presented excellent photocatalytic properties for producing hydrogen and decomposing organic pollutants simultaneously from wastewater without the addition of a sacrifice agent. The research revealed that the built-in electric field between g-C3N4 and Ti3C2 MXene could decrease the charge transfer resistance, leading to efficient photo charge separation, and the organic pollutant tetracycline (TC) could act as a sacrifice agent for splitting water. The H2 evolution rate of the CN-TCM-3 sample in deionized water with a sacrifice agent reached 105.4 μmol g−1 h−1, and the TC removal rate reached 100% within 120 min. The hydrogen production efficiency of CN-TCM-3 in the natural water of Slender West Lake without or with TC as a sacrifice agent was 2.3 μmol g−1 h−1 and 3.2 μmol g−1 h−1, respectively. The addition of TC improved the hydrogen production efficiency by 39%. This research indicated that the C/Ti3C2/g-C3N4 HM Schottky junctions could be a potential photocatalyst for producing hydrogen and decomposing organic pollutants in sewage simultaneously. [ABSTRACT FROM AUTHOR]

The introduction of unexpected solvent is inevitable in the crystallization process of rifampicin in industry, which could lead to products with different morphologies. Therefore, the study of crystal habit is needed for preparing rifampicin with better performance. In this work, an unreported solvate of rifampicin was prepared in n-butanol/acetone solvent. The interactions among solutes were analyzed through Hirshfeld surfaces and population fingerprints. The crystal morphology of the solvate in a vacuum was predicted by employing the attachment energy (AE) model, acquiring six habit faces. Surface structures of the faces were studied. Molecular electrostatic potentials (ESPs), concentration distribution and mean squared distribution (MSD) were then used to analyze the crystal face–solvent interface. By using the modified attachment energy (MAE) model, the morphology of rifampicin in n-butanol/acetone was finally obtained through calculations. The results show that the intermolecular interactions of solvate molecules were dominantly H⋯H and H⋯O/O⋯H contacts. Six morphologically important faces were found in the solvate crystal simulated in a vacuum, and among them, the (0 −2 0), (0 2 0), (0 0 1) and (1 0 0) faces were morphologically more important. It was found that the diffusion ability, surface structure and ESP were all important to the inhibitory effect. The morphology of the solvate was largely altered in the presence of n-butanol/acetone solvent and was consistent with the experiment result. [ABSTRACT FROM AUTHOR]

Currently, the aerobic oxidation of ethylbenzene to acetophenone has been found to be efficient and environmentally friendly, but homogeneous N-hydroxyphthalimide (NHPI), being active in the catalytic transformation suffers from separation and recovery. Here, NHPI was covalently anchored on commercial SiO2 using symmetric aromatic dianhydrides and (3-aminopropyl) triethoxysilane as precursors and a linking molecule, respectively, and the grafting bonds formed were convincing based on their IR absorption, chemical state(s) of N atoms, and the decomposition temperatures. Also, the catalyst synthesized using pyromellitic dianhydride (PMDA) as the precursor presented a grafting density of 0.70 mmolN–OH gsilica−1. The immobilized NHPI catalyzed the selective aerobic oxidation of ethylbenzene to acetophenone, and an ethylbenzene conversion of 63.8% and a selectivity to acetophenone of 79.0% were observed under optimal reaction conditions. An excellent catalytic reusability of the grafted NHPI catalyst was observed in repeated evaluations and this could be attributed to the confirmed stability of the structure and composition arising from the robust imide bonds anchoring. The anchoring method and the resulting NHPI catalysts could open access to converting organics with benzylic C–H bond(s) into their oxygenated value-added products, suggesting a promising application prospect. [ABSTRACT FROM AUTHOR]

Hydroxyapatite has found wide application in bone tissue engineering. Here we use a macroporous carbon template to generate highly ordered macroporous hydroxyapatite bioceramics composed of close-packed hollow spherical pores with interconnected channels. The template has advantages for the preparation of ordered materials. [ABSTRACT FROM AUTHOR]

Very few materials expand two-dimensionally under pressure, and this extremely rare phenomenon, namely negative area compressibility (NAC), is highly desirable for technological applications in pressure sensors and actuators. Hitherto, the few known NAC materials have dominantly been limited to 2D crystals bonded via coordination interactions while other 2D systems have not been explored yet. Here, we report the large NAC of a hydrogen-bonded 2D supramolecular coordination complex, Zn(CH 3 COO) 2 ·2H 2 O, with a synergistic microscopic mechanism. Our findings reveal that such an unusual phenomenon, over a wide pressure range of 0.15-4.44 GPa without the occurrence of any phase transitions, arises from the complex cooperation of intra-layer coordination and hydrogen-bonding interactions, and inter-layer van der Waals forces. In addition, we propose that these NAC crystals could have important applications as pressure-converting materials in ultrasensitive pressure sensing devices.

Mechanically robust, hollow carbon nanotube composite spheres that are permeable to large chemical species were prepared by a layer-by-layer assembly and templating technique.

Ordered arrays of oblate titania bodies were template synthesized using opal gel templates under uniaxial compression at ambient temperature during the favorable titania sol/gel process. The aspect ratio was controllable by the compression degree.