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Bi2WO6/Bi2MoO6 heterostructured photocatalys had been synthesized by a refluxing method. And the photocatalytic activity of Bi2WO6/Bi2MoO6 heterostructured photocatalysts was better than Bi2WO6. The enhancement in photocatalysis activity belonged to the match of energy level between the Bi2MoO6 and Bi2WO6. In order to further enhance the photocatalytic activity of Bi2WO6/Bi2MoO6, Bi2WO6/Bi2MoO6 was used to activate peroxymonosulfate to photodegradate methylene blue. The mechanism of activating peroxymonosulfate was proved by radical quenching experiment which revealed that sulfate radicals governed the removal of methylene blue.

This study presents a quadruple core/shell nanostructure of Ag@SiO 2 @Eu 3+ (tta) 3 Phen@Protein with both excellent fluorescent property and blood compatibility. Surface-plasma resonance (SPR) was utilised to enhance the fluorescence of europium (Eu 3+ ) complexes. In this situation, the fluorescence of Eu 3+ (tta) 3 Phen in the triple Ag@SiO 2 @Eu 3+ (tta) 3 Phen nanostructure is greatly enhanced. To increase the biocompatibility in blood, lysozyme was used to modify the surface of the above triple nanostructure to get the quadruple nanostructure of Ag@SiO 2 @Eu 3+ (tta) 3 Phen@lysozyme. Then, through the clinical anti-coagulation tests in human blood, the blood compatibility of Ag@SiO 2 @Eu 3+ (tta) 3 Phen@lysozyme is largely improved comparing with the triple nanostructure of Ag@SiO 2 @Eu 3+ (tta) 3 Phen, and the values of PT-S, APTT-S, TT-S, and AT-III of quadruple nanostructure blood sample with the modification of protein have the high correlation coefficients, 0.993-0.994, which means that the quadruple nanostructure of Ag@SiO 2 @Eu 3+ (tta) 3 Phen@lysozyme is close to the anti-coagulation property of physiological saline state (0.9% NaCl aqueous solution). Thus, this work provides two key properties of the quadruple nanostructure of Ag@SiO 2 @Eu 3+ (tta) 3 Phen@lysozyme: the excellent fluorescence and the outstanding blood compatibility. This nanomaterial can be applied to bio-imaging and bio-sensing in blood.

Bi2WO6 nanosheets were synthesized by a hydrothermal method with H2WO4 for the first time. The band structure of Bi2WO6 was investigated on the basis of density functional theory calculations. Bi2WO6 photocatalysts showed photocatalytic activity for the degradation of methylene blue under visible light irradiation. Kinetic studies using radical scavenger technologies suggested that holes were the dominant photo-oxidants. After hybridization with C3N4, the photocatalytic activity of Bi2WO6 was obviously enhanced. The enhanced photocatalytic activity of the C3N4/Bi2WO6 photocatalysts could be attributed to the effective separation of photogenerated e-/h+ pairs. The photogenerated holes on the valence band of Bi2WO6 can transfer to the highest occupied molecular orbital of C3N4via the well-developed interface, causing a reduction in the probability of e-/h+ recombination; consequently, large numbers of photogenerated holes led to the enhancement of the photocatalytic activity.

Highly monodispersed core-shell structured NaGdF4:Yb,Er@SiO2@Eu(TTA)3Phen(2-Thenoyltrifluoroacetone (TTA), 1,10-Phenanthroline monohydrate (Phen)) nanospheres were synthesized via two-step process. These nanospheres with diameter of 13 nm were encapsulated in SiO2 shell via micro-emulsion preparation. The ligand-sensitized Eu complexes attached to the outer surface of SiO2. The green (542 nm) and red (610 nm) light were excited by NIR and UV illumination, respectively. Thus, tunable photoresponse was possible in the core-shell structured hybrid nanocomposites. Under upconversion process, 5-fold increase at 542 nm and a 14-fold increase at 660 nm could be achieved under 980 nm laser, respectively.

A highly efficient Z-selective Knovenagel condensation reaction of isatins with nitroacetates mediated by TiCl4 and DMAP was described. The desired 2-nitro-3-ylideneoxindole acetates were obtained in good to excellent stereoselectivities and yields. Other activated methylene derivatives as well as 4-methylbenzenesulfonamide could provide good results too. This method makes it possible to obtain various unreported 3-ylideneoxindole derivatives under mild reaction conditions.

As the advanced functional materials, silver nanoparticles are potentially useful in various fields such as photoelectric, bio-sensing, catalysis, antibacterial and other fields, which are mainly based on their various properties. However, the properties of silver nanoparticles are usually determined by their size, shape, and surrounding medium, which can be modulated by various synthesis methods. In this review, the fabrication methods for synthesizing silver nanoparticles of different shapes and specific size are illustrated in detail. Besides, the corresponding properties and applications of silver nanoparticles are also discussed in this paper.

This paper presents strong fluorescence of spin-coated fluorescent solid organic dye films (SODF) enhanced by surface plasmonic resonance (SPR). In order to manifest the influence of SPR effect on enhancement of organic dye (OD) fluorescence, the organic dye embedded Ag@SiO2 fluorescent films were developed on the glass sheet substrate, in which Ag@SiO2 nanoparticles were embedded in the middle and organic dye was as upper layer. The morphology of the SODFs with and without Ag@SiO2 particles was studied by SEM and EDX, and the tests revealed that the Ag@SiO2 nanoparticles distributed evenly between glass sheet and OD layer. Optical properties were characterized by UV absorption and fluorescence spectroscopy; the lifetime of SODF was tested to discuss the mechanism of SPR enhancement of fluorescence. The results proved that the existence of Ag@SiO2 particles enhanced the fluorescence intensity for 7 times and thus proved the SPR effect for organic dye, especially when the organic dye is the solid films. Therefore, the most important is the creation that the SPR effect of Ag@SiO2 particles works very well under solid organic dye coverage.

An efficient catalyst-, base-, and oxidant-free direct cyanoalkylarylation of isocyanides with AIBN has been developed under mild conditions. This strategy provides an elusive and rapid access to a wide range of cyano-containing phenanthridine derivatives in good yields via a one-pot alkylation/cyclization radical-cascade process. The mild reaction conditions together with no need of any catalyst, base, or oxidant make this protocol environmentally benign and practical.

The combination of a transition-metal catalyst and organocatalyst was designed to achieve a highly enantioselective system for the allylic dearomatization reaction of naphthols with racemic secondary allylic alcohols. The desired β-naphthalenones, bearing an all-carbon quaternary center, were obtained in good yields with high chemo- and enantioselectivities. The cooperative catalytic system, involving a chiral iridium complex and phosphoric acid, provided measurable improvements in yields, and chemo- and enantioselectivities relative to single-catalyst systems. Control experiments indicated that the chiral iridium complex functions as a key species in the control of the absolute configuration, thus enabling the formation of both β-naphthalenone enantiomers by simply employing opposite enantiomeric ligands.