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Nanostructured black TiO2 materials prepared through a hydrogenation process have evoked significant interest in solar energy harvesting and conversion technologies due to their strong light absorption and utilization performances. Herein, by combining RMD simulations and DFT calculations, we systematically unravel the structural evolution mechanisms during the hydrogenation process of the nanosheets and nanoparticles of three different TiO2 phases: anatase, brookite, and rutile. Our results demonstrate that the reduction of TiO2 nanosheets occurs in three typical stages, namely the rapid escaping of free water and inner O atom diffusion, the slow free-water formation and the surface disorder, and eventually the dramatic stress deformation of the sheets. When it comes to the reduction of nanoparticles, orientation-relative anisotropic disorder has been observed. It is found that the preferable disordered surface is along {001} for anatase, {100} for brookite and {001} for rutile, causing anisotropic stress deformation. The surface reactivity of these three structures follows the order: rutile > anatase > brookite for both nanosheets and nanoparticles. Besides, the reduction rates are prominently dependent on the temperature, pressure, and H2 content. We expect that these results would provide theoretical guidance for the rational preparation of black TiO2 to enhance the development of clean energy. [ABSTRACT FROM AUTHOR]

MoS2/reduced graphene oxide (MoS2/rGO) composites are fabricated through a facile supramolecule-mediated hydrothermal route. The effects of the supramolecule (pillar[5]arene) on the microstructure and electrochemical lithium storage performance of the MoS2/rGO composites are investigated. It is found that the MoS2/rGO composites display a wrinkled thin flaky appearance, in which there are a lot of irregular pores and apertures. Few-layer MoS2 sheets are well dispersed and anchored on the rGO surface. When evaluated as a host material for lithium storage, the MoS2/rGO composite exhibits a much higher specific capacity of 1050–1140 mA h g−1 with excellent cyclic performance and a significantly enhanced high-rate capability of 815–875 mA h g−1 at a current density of 1000 mA g−1 in comparison with the pristine MoS2. The improved performance can be ascribed to the robust composite structure and the better synergic effects between few-layer MoS2 and rGO sheets. [ABSTRACT FROM AUTHOR]

The carrier scattering and relaxation dynamics in an n-type In0.83Ga0.17As ternary alloy are investigated by measuring the temperature dependent electron Hall mobilities and the hole lifetimes as a function of doping density. The dominant scattering mechanisms in temperature ranges of T ＜ 80 K, 80 ＜ T ＜ 120 K, and 120 ＜ T ＜ 300 K in lightly doped In0.83Ga0.17As are found to be impurity scattering, alloy disorder scattering and phonon scattering, respectively, while in heavily doped In0.83Ga0.17As alloy scattering dominates over the whole measured temperature range. By fitting the measured temperature dependent carrier lifetimes, the dominant carrier relaxation mechanisms in lightly doped In0.83Ga0.17As are identified to be the radiative recombination and the Shockley–Read–Hall effect for samples grown on InP and GaAs substrates, respectively. The lifetime in heavily doped In0.83Ga0.17As is below 10 ns with an Auger dominated recombination. Lastly, photoluminescence as well as the light absorption measurements are performed, showing that the grown lightly doped In0.83Ga0.17As has a high optical quality comparable to the lattice-matched In0.53Ga0.47As. [ABSTRACT FROM AUTHOR]

A novel diethynyl functionalized pillar[5]arene, that is a pentabenzenacyclodecaphane derivative, has been synthesized and polymerized with p-dihalobenzene to form a fishing rod-like conjugated polymer, where one of the benzenes in the pillar[5]arene rings is incorporated into a poly(arylene ethynylene) backbone. [ABSTRACT FROM AUTHOR]

A pillar[6]arene with mono(ethylene oxide) groups was synthesized and it formed a highly stable inclusion complex with diquat, while the pillar[5]arene analogue did not. [ABSTRACT FROM AUTHOR]

Two 2 : 3 copillar[5]arene constitutional isomers were prepared and host–guest complexation of their derivatives with dicarboxylic acid sodium salts in water was investigated. [ABSTRACT FROM AUTHOR]

By the introduction of trimethylammonium groups at both upper and lower rims, a cationic water-soluble pillar[5]arene was prepared, which forms a stable 1 : 1 host–guest complex with sodium 1-octanesulfonate in water. [ABSTRACT FROM AUTHOR]

(o-Phenyleno)naphthalene dianhydride 7 was synthesized by a six-step reaction. Imidizations of 7 led to various diimides 8. Their optical and electrochemical properties hold promise for organic electronics.

A new water-soluble pillar[5]arene containing ten imidazolium groups was prepared. It can be used as a stabilizer to fabricate gold nanoparticles smaller than 6 nm in water.