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The support used in a composite catalyst has an important influence on the catalytic performance of the catalyst. Amorphous metals have good electron-transfer properties and the presence of defect structures on the surface will introduce additional active sites and should be excellent catalyst supports. In this study, an Ag@AgCl composite catalyst with amorphous Cu (a-Cu) as the support is prepared by a two-step precipitation method at room temperature and a light irradiation reduction method. Compared to the Ag@AgCl and a-Cu, the catalytic rate of the Ag@AgCl/a-Cu composite catalytic rate was 2.04 times and 6.69 times faster during the reduction of 4-NP in NaBH4aqueous solution. The high-performance catalytic efficiency and reusability of Ag@AgCl/a-Cu may be attributed to the synergistic effect between Ag@AgC and amorphous metal elements. This work may provide an effective reference for the synthesis of high activity catalysts using amorphous metals as supports.

We have studied the effect of organic cation doping with dimethylammonium (DMA+), ethylammonium (EA+), and guanidinium (GA+) on the properties of the CsPbI3 perovskite by performing first-principles calculations. It was found that these dopants, especially DMA+, can significantly improve the phase stability of the desired α phase of CsPbI3 by compressing the transition temperature between the photoactive α phase (cubic perovskite structure) and the photoinactive δ phase (orthorhombic structure). However, the incorporation of organic cations decreases the absorption coefficient of the CsPbI3 perovskite in the visible spectrum. The details of the improvement of the phase stability and the degradation of the optical properties arising from the organic dopants are revealed. Our results are valuable for developing stable and high performance hybrid perovskite photovoltaic materials.

In this study, multifunctional bovine serum albumin (BSA) nanoparticles were fabricated via a green approach with high efficiency. Folic acid (FA) was conjugated to dextran (DEX) through an esterification reaction, and BSA-DEX-FA conjugate was produced by Maillard reaction. Superparamagnetic Fe

Tungsten trioxide (WO3) nano-material is an indirect band gap semiconductor with gap energy of 2.5–2.8 eV and has multifunctional in electrochromic, optochromic, gaschromic and photocatalytic applications. In this work, we report a novel and facile approach for the direct fabricates the 3D flower-like WO3. The WO3 were assembled from ultrathin nanosheets as the building blocks and the thickness of sheets only have 10 nm and exposed (002) facets on the top and bottom. The as-prepared WO3 have high special surface area and were employed as scaffolding to deposit the Ag nanoparticles on the surface by the method of in situ redox reaction. The Ag nanoparticles deposition on the surface of WO3 flowers significant enhances the absorption in visible light by the effect of SPR. The photocatalytic performance of Ag@WO3 plasmonic photocatalyst is obviously improved when small amounts of Ag particles are deposited on WO3 photocatalyst surface. This study provided new insights into the fabrication and practical application of high-performance photocatalysts in degrading organic pollutants.

We have studied the effect of organic cation doping with dimethylammonium (DMA

Metal ion or non-metal ion doping is a simple and effective method to improve the photocatalytic efficiency. The previous research showed that metal ion and non-metal ion could enhance the photocatalytic efficiency of BiOCl through different mechanisms. Since aluminum is an amphoteric metal elemental, Al3+ doping may exhibit special properties. To study the effect of Al3+ doping on the structure of BiOCl and its photocatalytic performance, Al-doped BiOCl microspheres which were assembled by nanosheets with exposed (0 0 1) crystal plane were prepared by solvothermal method. The prepared samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS). The degradation results displayed that Al-10.0-BiOCl with a doping amount of 10 atom% (Al: Bi = 1:10) was the optimized sample and it could degrade 91.1% of tetracycline hydrochloride (TC, 100 mg/L) within 60 min under simulated sunlight irradiation. It was confirmed ·O2– was the main active substance during the catalytic degradation of TC and the high photocatalytic performance may be mainly attributed to the large specific surface area, wide range of sunlight absorption and high charge separation efficiency. To study the effect of the Al3+ doping on the structure of BiOCl and its photocatalytic performance, novel Al-doped BiOCl microspheres assembled by nanosheets with exposed (0 0 1) crystal plane were prepared by a solvothermal method. The samples were characterized and the photocatalytic activity was evaluated by degradating tetracycline hydrochloride under simulated sunlight irradiation. The results showed that Al-BiOCl with a doping content of 10 at% (Al: Bi = 1:10) exhibited optimal photocatalytic performance, and the high photocatalytic performance of Al-BiOCl may be mainly attributed to the large specific surface area, wide range of sunlight absorption and high charge separation efficiency.

In this study, nitrogen and sulfur co-doped carbon dots (NSCDs) were fabricated by microwave-assisted one-pot synthesis using vitamin C and thiourea as precursors. The as-prepared NSCDs demonstrated excellent properties, including aqueous dispensability, strong fluorescence emission, excellent environmental stability, high selectivity, and sensitivity toward Fe3+ ions. The NSCD-based material can be used as a “turn off” fluorescent probe for detecting Fe3+ ions at a low detection limit (4.2 nM). In addition, the “turn off” and “turn on” of NSCD fluorescent probe could be modulated by adding Fe3+ and EDTA, indicating weak interaction between the Fe3+ ions and NSCDs.

The TiO2 nanosheets with exposed (010) facets were synthesized via facile surfactant self-assembly. Then, the TiO2 sheets were employed as scaffolding and deposited Ag/AgBr particles via improved oil/water self-assembly method. The TEM results suggested that Ag/AgBr particles well dispersed on the surface of TiO2 sheets with diameter 1–4 nm. The modified of Ag/AgBr enhanced the absorption in the visible light region, which was due to surface plasmonic resonance (SPR) of the metallic Ag clusters formed on the surface of AgBr particle. The as-prepared hierarchical composites photocatalyst Ag/AgBr/TiO2 exhibited excellent photocatalytic activity under nature solar-light irradiation and degraded ∼91.7% of Rhodamine (RhB) within 60 min. The degradation of colorless Bisphenol (BPA) further confirmed the photocatalytic abilities of Ag/AgBr/TiO2. The quenching tests exhibited that the Ag/AgBr/TiO2 composites photocatalytic degradation organic pollutions were mainly dominated by O2− oxidation reactions, while the h+ and OH have a minor contribution. The improved photocatalytic activities can be attributed to the suitable size of Ag/AgBr particles, abundant surface active sites, effective photogenerated electron-hole pair's separation, which significantly improve the photocatalytic activity.

Visible-light sensitive photocatalyst Ag/AgBr/Bi2WO6 was successfully synthesized by oil/water self-assembly method. The crystalline structure, morphologies and optical properties of the as-prepared samples were investigated. The results revealed that the Ag/AgBr successfully introduced into the surface of Bi2WO6. The modified of Ag/AgBr enhanced the absorption in the visible-light region, due to surface plasmonic resonance of the metallic Ag. The activities of as-prepared samples were investigated by the degradation of RhB and phenol under the visible-light. Experimental results revealed that the Ag/AgBr/Bi2WO6 composites exhibit high visible-light photocatalytic activity compared with that of pure Ag/AgBr and Bi2WO6.

In this study, multifunctional bovine serum albumin (BSA) nanoparticles were fabricated via a green approach with high efficiency. Folic acid (FA) was conjugated to dextran (DEX) through an esterification reaction, and BSA–DEX–FA conjugate was produced by Maillard reaction. Superparamagnetic Fe3O4 nanocrystals with a size about 10 nm were loaded into BSA–DEX–FA nanoparticles through a heat treatment which induces BSA gelation. Doxorubicin (DOX) was loaded into Fe3O4/BSA–DEX–FA nanoparticles by a diffusion process. Fe3O4/BSA–DEX–FA and DOX/Fe3O4/BSA–DEX–FA nanoparticles have a size of about 100 nm, good stability, superior transversal R2 relaxation rate of larger than 360 (mM)−1 s−1, as well as FA receptor-targeted and magnetically guided functions. Fe3O4/BSA–DEX–FA nanoparticles have excellent biocompatibility. By application of an external magnetic field close to tumor, DOX/Fe3O4/BSA–DEX–FA nanoparticles can effectively enhance the tumor inhibition rate and prolong the life time of H22 tumor-bearing mice, and Fe3O4/BSA–DEX–FA nanoparticles can significantly improve the tumor MRI of KB tumor-bearing mice. This study demonstrates that Fe3O4/BSA–DEX–FA and DOX/Fe3O4/BSA–DEX–FA nanoparticles are suitable systems for tumor diagnosis and therapy.

In this study, Ag-doped TiO2 hollow microspheres were synthesized by a template-free route, and their photocatalytic performance and catalytic mechanism were investigated. The hollow microspheres were characterized by x-ray diffraction, scanning electron microscopy, transmission electron microscopy, x-ray photoelectron spectroscopy and UV–vis spectroscopy. Ag-doped hollow TiO2 microspheres exhibited excellent photocatalytic performance for tetracycline hydrochloride (TC) in water. TC degradation follows pseudo first-order kinetics, and hydroxyl radical (OH) and holes (h+) were active substances in the photocatalytic reaction.

CdS/PAM nanocomposites have been successfully synthesized in situ via a ultrasound-assisted route under ambient condition, employing CdCl(2) and Na(2)S(2)O(3) as Cd(2+) and S(2-) ion sources and acrylamide (AM) and (NH(4))(2)S(2)O(8) as organic monomers and initiating reagents, respectively. The results from X-ray powder diffraction (XRD) analysis and the IR spectrum of the final product showed the formation of CdS nanoparticles and the polymerization of AM monomers. SEM observations showed that the CdS/PAM nanocomposites could film on the quartz substrate and some holes in which many nanorods regularly arranged distributed on the film. The UV-vis absorption and PL spectra of CdS/PAM nanocomposites obviously differed from those of CdS nanoparticles prepared under the same conditions due to the presence of PAM. The electrochemical research showed that CdS/PAM nanocomposites had a stronger ability to promote electron transfers between Hb and the Au electrode than CdS nanoparticles prepared under the same conditions. A possible formation mechanism was also suggested based on the results of experiments.

We herein report a simple, rapid, and eco-friendly chemical route to the one-pot synthesis of bimetallic PtPd alloy cubic nanocomposites under microwave irradiation. During this process, water was employed as an environmentally benign solvent, while dimethylformamide served as a mild reducing agent, and polyvinylpyrrolidone was used as both a dispersant and a stabilizer. The structure, morphology, and composition of the resulting alloy nanocomposites were examined by x-ray diffraction, transmission electron microscopy, and energy dispersive x-ray spectroscopy. A detailed study was then carried out into the catalytic activity of the PtPd nanocomposites with a Pt:Pd molar ratio of 50:50 in the reduction of 4-nitrophenol (4-NP) by sodium borohydride as a model reaction. Compared with pristine Pt and Pd monometallic nanoparticles (PtNPs and PdNPs), the bimetallic PtPd alloy nanocomposites exhibited enhanced catalytic activities and were readily recyclable in the reduction of 4-NP due to synergistic effects.

Biocompatible and biodegradable doxorubicin loaded nanoparticles with targeting ability were prepared from BSA-dextran-folic acid conjugate via a pH adjustment and heating process. The BSA-dextran-folic acid conjugate was produced by an esterification reaction between folic acid and dextran and then the Maillard reaction between the modified dextran and BSA. The nanoparticles have a size about 90nm and excellent dispersibility at pH 7.4 aqueous solution. The doxorubicin loading efficiency and loading amount of the nanoparticles are larger than 90% and 14%, respectively. The antitumor activity and toxicity of the nanoparticles were evaluated through murine ascites hepatoma H22 tumor-bearing mice. The nanoparticles allow the administration of the doxorubicin with higher dose. At doxorubicin dose of 10mg/kg, the nanoparticles can achieve 88.9% of the tumor inhibition rate that is the same as the free doxorubicin at the dose of 5mg/kg. Importantly, the nanoparticles can decrease the toxicity of doxorubicin that results in a significant increase of the average life time in comparison with the free doxorubicin as well as the nanoparticles without folic acid.