Clinical course and risk factors for mortality of adult inpatients with COVID-19 in Wuhan, China: a retrospective cohort study.

Ju Mei,†,‡,∥ Nelson L. C. Leung,†,‡,∥ Ryan T. K. Kwok,†,‡ Jacky W. Y. Lam,†,‡ and Ben Zhong Tang*,†,‡,§ †HKUST-Shenzhen Research Institute, Hi-Tech Park, Nanshan, Shenzhen 518057, China ‡Department of Chemistry, HKUST Jockey Club Institute for Advanced Study, Institute of Molecular Functional Materials, Division of Biomedical Engineering, State Key Laboratory of Molecular Neuroscience, Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China Guangdong Innovative Research Team, SCUT-HKUST Joint Research Laboratory, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, China

Aggregation-Induced Emission: Together We Shine, United We Soar!

As a fascinating conjugated polymer, graphitic carbon nitride (g-C3N4) has become a new research hotspot and drawn broad interdisciplinary attention as a metal-free and visible-light-responsive photocatalyst in the arena of solar energy conversion and environmental remediation. This is due to its appealing electronic band structure, high physicochemical stability, and “earth-abundant” nature. This critical review summarizes a panorama of the latest progress related to the design and construction of pristine g-C3N4 and g-C3N4-based nanocomposites, including (1) nanoarchitecture design of bare g-C3N4, such as hard and soft templating approaches, supramolecular preorganization assembly, exfoliation, and template-free synthesis routes, (2) functionalization of g-C3N4 at an atomic level (elemental doping) and molecular level (copolymerization), and (3) modification of g-C3N4 with well-matched energy levels of another semiconductor or a metal as a cocatalyst to form heterojunction nanostructures. The constructi...

Graphitic Carbon Nitride (g-C3N4)-Based Photocatalysts for Artificial Photosynthesis and Environmental Remediation: Are We a Step Closer To Achieving Sustainability?

Nanocrystals are fundamental to modern science and technology. Mastery over the shape of a nanocrystal enables control of its properties and enhancement of its usefulness for a given application. Our aim is to present a comprehensive review of current research activities that center on the shape-controlled synthesis of metal nanocrystals. We begin with a brief introduction to nucleation and growth within the context of metal nanocrystal synthesis, followed by a discussion of the possible shapes that a metal nanocrystal might take under different conditions. We then focus on a variety of experimental parameters that have been explored to manipulate the nucleation and growth of metal nanocrystals in solution-phase syntheses in an effort to generate specific shapes. We then elaborate on these approaches by selecting examples in which there is already reasonable understanding for the observed shape control or at least the protocols have proven to be reproducible and controllable. Finally, we highlight a number of applications that have been enabled and/or enhanced by the shape-controlled synthesis of metal nanocrystals. We conclude this article with personal perspectives on the directions toward which future research in this field might take.

Shape‐Controlled Synthesis of Metal Nanocrystals: Simple Chemistry Meets Complex Physics?

A method is used for preparing gold NRs with aspect ratios ranging from 1.5 to 10 for which the surface plasmon absorption maxima are between 600 and 1300 nm. This method has been adapted from a previously published seed-mediated growth method (Jana et al. Adv. Mater. 2001, 13, 1389). The disadvantages and limitations of the earlier method (i.e., formation of noncylindrical NRs, φ-shaped particles, and formation of a large fraction of spherical particles) have been overcome by use of a hexadecyltrimethylammonium bromide (CTAB)-capped seed instead of a citrate-capped one. In a single-component surfactant system, the silver content of the growth solution was used to grow NRs to a desired length. This results in reproducible formation of NRs with aspect ratios ranging from 1.5 to 4.5. To grow longer NRs with aspect ratios ranging from 4.6 to 10, a binary surfactant mixture composed of benzyldimethylhexadecylammoniumchloride (BDAC) and CTAB was used. NRs are grown in this mixture either by aging or by additio...

Preparation and Growth Mechanism of Gold Nanorods (NRs) Using Seed-Mediated Growth Method

Supramolecular Chirality in Self-Assembled Systems

In this paper, we have reported that well-defined graphene oxide (GO) enwrapped Ag/AgX (X = Br, Cl) nanocomposites, which are composed of Ag/AgX nanoparticles and gauze-like GO nanosheets, could be facilely fabricated via a water/oil system. We have shown that thus-synthesized GO-based hybrid nanocomposites could be used as a stable plasmonic photocatalyst for the photodegradation of methyl orange (MO) pollutant under visible-light irradiation. Compared with the corresponding bare Ag/AgX nanospecies, the GO-involved nanocomposites (Ag/AgX/GO) display distinctly enhanced photocatalytic activities. The hybridization of Ag/AgX with GO nanosheets causes the nice adsorptive capacity of Ag/AgX/GO to MO molecules, the smaller size of the Ag/AgX nanoparticles in Ag/AgX/GO, the facilitated charge transfer, and the suppressed recombination of electron–hole pairs in Ag/AgX/GO. It is suggested that these multifactors, resulting from the hybridization of GO, contribute to the enhanced photocatalytic performance observ...

Graphene oxide enwrapped Ag/AgX (X = Br, Cl) nanocomposite as a highly efficient visible-light plasmonic photocatalyst.

A versatile and scalable mixed solvent strategy was developed to prepare monolayer C3N4 nanosheets with tunable concentration for the first time. This approach could also be used to prepare other 2D nanosheets from their layered materials (such as MoS2, BN, WS2 etc.). The structural features and intrinsic semiconductor properties of the as-prepared C3N4 nanosheets have been investigated in detailed. The photocatalytic activities were evaluated by photocatalytic oxidation of both benzyl alcohol and rhodamine B (RhB) under visible light irradiation. Results showed that the as-prepared monolayer C3N4 nanosheets with thickness of 0.4 nm still retained the structural features of g-C3N4 layer. The functionalities of C3N4 nanosheets well inherited from the layered parent counterpart. Furthermore, due to the exceptionally high 2D anisotropy, C3N4 nanosheets showed the distinctive physicochemical properties and unique electronic structures, such as high surface area, lower surface defects, stronger reduction ability of the photogenerated electrons, increased photoelectric response, and promoted the charge-carrier migration and separation. All of these favorable factors co-contributed to the greatly improved photocatalytic activities over C3N4 nanosheets compared with those of its bulk counterpart.

Efficient synthesis of monolayer carbon nitride 2D nanosheet with tunable concentration and enhanced visible-light photocatalytic activities

Currently, the development of circularly polarized luminescent (CPL) materials has drawn extensive attention due to the numerous potential applications in optical data storage, displays, backlights in 3D displays, and so on. While the fabrication of CPL-active materials generally requires chiral luminescent molecules, the introduction of the "self-assembly" concept offers a new perspective in obtaining the CPL-active materials. Following this approach, various self-assembled materials, including organic-, inorganic-, and hybrid systems can be endowed with CPL properties. Benefiting from the advantages of self-assembly, not only chiral molecules, but also achiral species, as well as inorganic nanoparticles have potential to be self-assembled into chiral nanoassemblies showing CPL activity. In addition, the dissymmetry factor, an important parameter of CPL materials, can be enhanced through various pathways of self-assembly. Here, the present status and progress of self-assembled nanomaterials with CPL activity are reviewed. An overview of the key factors in regulating chiral emission materials at the supramolecular level will largely boost their application in multidisciplinary fields.

Circularly Polarized Luminescence in Nanoassemblies: Generation, Amplification, and Application.

Transfer of both chirality and energy information plays an important role in biological systems. Here we show a chiral donor π-gelator and assembled it with an achiral π-acceptor to see how chirality and energy can be transferred in a composite donor-acceptor system. It is found that the individual chiral gelator can self-assemble into nanohelix. In the presence of the achiral acceptor, the self-assembly can also proceed and lead to the formation of the composite nanohelix. In the composite nanohelix, an energy transfer is realized. Interestingly, in the composite nanohelix, the achiral acceptor can both capture the supramolecular chirality and collect the circularly polarized energy from the chiral donor, showing both supramolecular chirality and energy transfer amplified circularly polarized luminescence (ETACPL).

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Minghua Liu

Papers

Supramolecular Chirality in Self-Assembled Systems

Graphene oxide enwrapped Ag/AgX (X = Br, Cl) nanocomposite as a highly efficient visible-light plasmonic photocatalyst.

Efficient synthesis of monolayer carbon nitride 2D nanosheet with tunable concentration and enhanced visible-light photocatalytic activities

Circularly Polarized Luminescence in Nanoassemblies: Generation, Amplification, and Application.

Chirality and energy transfer amplified circularly polarized luminescence in composite nanohelix