Silicon nanowires (SiNWs) are widely used as photocathodes because of their large electrochemically available surface-area density and inherent ability to decouple light absorption from the transport of minority carriers. In order to minimize overpotential for solar-driven hydrogen (H) production, a combination of an ultrathin molybdenum disulfide (MoS) layer with SiNWs as photocathode has attracted much attention. Herein, for the first time, this study presents the synthesis of a composite photocathode via direct growth of ultrathin MoS nanosheets on SiNWs (referred to as SiNWs/MoS) by one-step chemical vapor deposition (CVD). Due to the high surface-area density of the arrays of SiNWs, the discontinuous MoS nanosheets grown on the SiNWs achieved a much higher density of active sites. Moreover, the coating of MoS on the SiNWs was found to protect the photocathode during the photoelectrochemical (PEC) reaction. A high efficiency with photocurrent j of 16.5 mA cm (at 0 V vs. reversible hydrogen electrode) and an excellent stability over 48 h of PEC operation were achieved under a simulated 1 sun irradiation.

A practical protocol for the preparation of quinoxaline-2,3(1H,4H)-diones through direct C (sp 2 )À H hydroxylation of quinoxalin-2(1H)-ones in recyclable DL-α-Tocopherol methoxypolyethylene glycol succinate solution (2 wt% in water) (TPGS-750-M/H 2 O) was developed. The target products were exclusively generated and could be collected through extraction and recrystallization.

Nanostructured molybdenum disulfide (MoS) has been considered as one of the most promising catalysts in the hydrogen evolution reaction (HER), for its approximately intermediate hydrogen binding free energy to noble metals and much lower cost. The catalytically active sites of MoS are along the edges, whereas thermodynamically MoS favors the presence of a two-dimensional (2-D) basal plane and the catalytically active atoms only constitute a small portion of the material. The lack of catalytically active sites and low catalytic efficiency impede its massive application. To address the issue, we have activated the basal plane of monolayer 2H MoS through an ultrathin alumina mask (UTAM)-assisted nanopore arrays patterning, creating a high edge density. The introduced catalytically active sites are identified by Cu electrochemical deposition, and the hydrogen generation properties are assessed in detail. We demonstrate a remarkably improved HER performance as well as the identical catalysis of the artificial edges and the pristine metallic edges of monolayer MoS. Such a porous monolayer nanostructure can achieve a much higher edge atom ratio than the pristine monolayer MoS flakes, which can lead to a much improved catalytic efficiency. This controllable edge engineering can also be extended to the basal plane modifications of other 2-D materials, for improving their edge-related properties.

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The rapid development of chiral inorganic nanostructures has greatly expanded from intrinsically chiral nanoparticles to more sophisticated assemblies made by organics, metals, semiconductors, and their hybrids. Among them, lots of studies concerning on hybrid complex of chiral molecules with achiral nanoparticles (NPs) and superstructures with chiral configurations were accordingly conducted due to the great advances such as highly enhanced biocompatibility with low cytotoxicity and enhanced penetration and retention capability, programmable surface functionality with engineerable building blocks, and more importantly tunable chirality in a controlled manner, leading to revolutionary designs of new biomaterials for synergistic cancer therapy, control of enantiomeric enzymatic reactions, integration of metabolism and pathology via bio-to nano or structural chirality. Herein, in this review our objective is to emphasize current research state and clinical applications of chiral nanomaterials in biological systems with special attentions to chiral metal- or semiconductor-based nanostructures in terms of the basic synthesis, related circular dichroism effects at optical frequencies, mechanisms of induced optical chirality and their performances in biomedical applications such as phototherapy, bio-imaging, neurodegenerative diseases, gene editing, cellular activity and sensing of biomarkers so as to provide insights into this fascinating field for peer researchers.

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Mechanochromic luminescence, thermally activated delayed fluorescence, aggregation-induced emission, and electroluminescence properties are combined in a single organic molecule, 2-(carbazol-9-yl)-anthraquinone (Cz-AQ).