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61.
Hierarchically disorder sponge-like macro/mesoporous titania was prepared by adding distilled water dropwise to a coating of tetrabutyl titanate. The results reveal that the un-calcined samples show obvious photocatalytic activity and multi-modal pore-size distribution. With increasing calcination temperatures, the photocatalytic activity and crystallinity increase. At 400°C, the calcined sample shows the highest photocatalytic activity. Further increasing the calcination temperatures results in the decrease of photocatalytic activity due to the drastic decrease of specific surface areas. However, the 600°C-calcined sample exhibits the highest specific photocatalytic activity due to high anatase crystallinity.  相似文献   
62.
This review briefly summarizes recent advances in fluorine ions-mediated morphology control of anatase TiO(2) in the forms of nanotube arrays, nanosheets with high-energy facets, and hollow spheres. The correlations between the enhanced photocatalytic activity and structural and morphological modifications of anatase TiO(2) by fluorine ions are addressed.  相似文献   
63.
Bimodal nanocrystalline mesoporous TiO2 powders with highly photocatalytic activity were prepared by a hydrothermal method using tetrabutylorthotitanate as precursor, and then dried in microwave oven. The prepared samples were characterized by XRD, SEM, TEM, HRTEM and N2 adsorption-desorption measurement. The photocatalytic activity was evaluated by the photocatalytic degradation of acetone in air under UV light irradiation at room temperature. The effects of microwave drying on the microstructures and photocatalytic activity of the TiO2 powders were investigated and discussed. The results show that microwave drying not only promotes the growth of the pores but also greatly reduces the state of agglomeration within the powders. All the microwave-dried TiO2 powders show higher photocatalytic activity than Degussa P-25 (P25) and the TiO2 powders dried by conventional method.  相似文献   
64.
Bladder cancer (BC) is a prevalent disease with high morbidity and mortality; however, in vivo optical imaging of BC remains challenging because of the lack of cancer-specific optical agents with high renal clearance. Herein, a macromolecular reporter (CyP1) was synthesized for real-time near-infrared fluorescence (NIRF) imaging and urinalysis of BC in living mice. Because of the high renal clearance (ca. 94 % of the injection dosage at 24 h post-injection) and its cancer biomarker (APN=aminopeptidase N) specificity, CyP1 can be efficiently transported to the bladder and specially turn on its NIRF signal to report the detection of BC in living mice. Moreover, CyP1 can be used for optical urinalysis, permitting the ex vivo tracking of tumor progression for therapeutic evaluation and easy translation of CyP2 as an in vitro diagnostic assay. This study not only provides new opportunities for non-invasive diagnosis of BC, but also reveals useful guidelines for the development of molecular reporters for the detection of bladder diseases.  相似文献   
65.
ZnIn2S4 microspheres (ZIS MSs) were for the first time decorated with carbon quantum dots (CQDs) and platinum nanoparticles (NPs) as dual co‐catalysts of for photocatalytic H2 production. The ZIS MSs co‐loaded with CQDs and Pt exhibited a high photocatalytic H2 production rate of 1032.2 μmol h?1 g?1 with an apparent quantum efficiency of 2.2 % (420 nm) in triethanolamine aqueous solution under visible‐light irradiation, which was much higher than the respective photocatalytic rates of pure ZIS, Pt loaded ZIS, and CQDs‐decorated ZIS. Such a great enhancement was attributed to the integrative effect of good crystallization, enhanced light absorption, high electrical conductivity of CQDs, and the vectorial electron transfer from ZIS to CQDs and Pt NPs (ZIS→CQDs→Pt).  相似文献   
66.
We report the fabrication of BiOCl nanoflake film by a simple and reliable hydrolysis of BiCl(3) ethanol solution at room temperature. The as-prepared film, when modified with 1H,1H,2H,2H,-perfluorodecyltrichlorosilane (FDTS), exhibits excellent superhydrophobicity and long-term durability under UV light irradiation for the first time.  相似文献   
67.
Optical imaging plays a crucial role in biomedicine. However, due to strong light scattering and autofluorescence in biological tissue between 650–900 nm, conventional optical imaging often has a poor signal-to-background ratio and shallow penetration depth, which limits its ability in deep-tissue in vivo imaging. Second near-infrared fluorescence, chemiluminescence, and photoacoustic imaging modalities mitigate these issues by their respective advantages of minimized light scattering, eliminated external excitation, and ultrasound detection. To enable disease detection, activatable molecular probes (AMPs) with the ability to change their second near-infrared fluorescence, chemiluminescence, or photoacoustic signals in response to a biomarker have been developed. This Minireview summarizes the molecular design strategies, sensing mechanisms, and imaging applications of AMPs. The potential challenges and perspectives of AMPs in deep-tissue imaging are also discussed.  相似文献   
68.
Using bimetallic Prussian blue analogue (PBA) as a precursor is effective for preparing electrocatalysts for the oxygen evolution reaction (OER); however, the role of these PBA-derived catalysts in the OER is still ambiguous. Herein, by simply controlling synthesis temperature, a bimetallic PBA-derived O,N-codoped Ni–Fe carbide, can be well tuned to optimize structure and OER performance. Importantly, by a series of ex situ and in situ investigations, real active species of NiFeOxHy are in situ formed on the surface during the OER, which reveals a “pre-catalyst” role of O,N-codoped Ni–Fe carbides. Furthermore, it has been successfully applied to highly efficient Zn–air batteries and outplays its RuO2 counterpart. When applied to photoelectrocatalytic water oxidation as the co-catalyst, it improves the performance of the BiVO4 photoanode by enhancing hole collecting and transporting ability. We believe this research not only provides a highly efficient and low-cost electrocatalyst for the OER, but also unveils the “pre-catalyst” role of PBA-derived materials in energy-storage and conversion devices.  相似文献   
69.
自1990年Burroughes等首次报道聚对亚苯亚乙烯的电致发光以来,由于电致发光高分子材料在平面显示(特别是大面积显示)方面具有其他显示材料难以比拟的优势,因而近年来受到人们的广泛关注,在合成方法、加工性能、发光颜色的调控以及器件性能等多方面取得显著进展,不  相似文献   
70.
Little hollow! Monodisperse ZnS hollow nanospheres (see figure) of about 200 nm in size have been fabricated on a large scale by a hydrothermal method and they show good photocatalytic activity in the decolorization of an aqueous solution of rhodamine B under UV irradiation.

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