Construction of a type-II BiVO4/BiOI heterojunction for efficient photoelectrocatalytic degradation of ß-naphthol and coal gasification wastewater under visible-light irradiation.

Herein, a novel type-II BiVO4/BiOI (BVOI) heterojunction electrode material was successfully fabricated by using a facile two-step electrodeposition approach. The experimental results revealed that BiOI nanosheets were deposited onto the surface of BiVO4 particles successfully, with the special morphology providing more active sites, which was beneficial to the improvement of PEC performance. According to the electrochemical performance tests, it could be observed that the construction of a heterojunction effectively promoted the separation of photoinduced electron-hole pairs and increased the transfer rate of surface charges. Under visible-light irradiation, the BVOI-300 photoanode possessed the highest PEC ß-naphthol degradation rate at pH = 7, which approximately reached 82%, whose corresponding kinetic constant was 1.4 and 1.5 times higher than those of pure BiVO4 and BiOI. After five cycles, the degradation rate still remained at 64.61%. The band structure of the BVOI electrode was deduced, and the PEC mechanism of the BVOI electrode was investigated through the radical trapping quenching experiments and ESR test, which indicated that the ˙OH, h+ and ˙O2- radicals were crucial active species in the PEC ß-naphthol degradation process. For the BVOI-300 working electrode, the TOC content of coal gasification wastewater (CGW) decreased from 94.44 to 54.4 mg L-1, and the removal rate reached 42.4%. GC-MS was used to identify the organic components of coal gasification wastewater, which was expected to provide reference for remedying actual gasification wastewater containing refractory organic pollutants and offer a new development direction for the treatment of actual coal chemical wastewater.

N/S Co-Doped Graphene Aerogels as Superior Anode Materials for High-Rate Lithium-Ion Batteries.

The nitrogen and sulfur co-doped graphene aerogel (SNGA) was synthesized by a one-pot hydrothermal route using graphene oxide as the starting material and thiourea as the S and N source. The obtained SNGA with a three-dimensionally hierarchical structure, providing more available pathways for the transport of lithium ions. The existing form of S and N was regulated by changing the calcination temperature and thiourea doping amount. The results revealed that high temperature could decompose -SOX- functional groups and promote the transformation of C-S-C to C-S, ensuring the cyclic stability of electrode materials, and increasing the thiourea dosage amount introduced more pyridine nitrogen, improving the multiplicative performance of electrode materials. Benefiting from the synergistic effect of sulfur and nitrogen atoms, the prepared SNGA showed superior rate capability (107.8 mAh g-1 at 5 A g-1), twice more than that of GA (52.8 mAh g-1), and excellent stability (232.1 mAh g-1 at 1 A g-1 after 300 cycles), 1.85 times more than that of GA (125.6 mAh g-1). The present study provides a detailed report on thiourea as a dopant to provide a sufficient basis for SNGA and a theoretical guide for further modifying.

The development of an indirect competitive immunomagnetic-proximity ligation assay for small-molecule detection.

The development of an indirect competitive immunomagnetic-proximity ligation assay (ICIPLA), which is a novel method for detecting small molecules, is described in this report. Free small molecules in samples can be detected using a proximity ligation assay (PLA); the detection is based on the proximity effect caused by a high concentration of small molecule-BSA conjugates bound to streptavidin magnetic beads. As an indirect format competitive immunoassay, the ICIPLA method has the advantage in that the quantity of monoclonal antibody (mAb) used for small-molecule detection is 8-fold lower than that required for the competitive immunomagnetic-proximity ligation assay (CIPLA) described in our previous work. Small molecules can be detected using a single monoclonal antibody, and the PLA method can be used to amplify high-performance signals. In this work, the small molecular compound ractopamine (RAC) was selected as a target for ICIPLA. The limit of detection (LOD) was 0.01 ng ml(-1), and the method exhibited a broad dynamic range of up to six orders of magnitude. We also employed the ICIPLA method to detect RAC in serum, urine, and muscle extracts; the results indicated that the LOD and dynamic range were not altered. The cross-reactivity studies showed that the cross-reactivity values for all RAC analogs were below 0.01%. These results suggest that ICIPLA is a sensitive, specific and practical method for small-molecule detection. This is the first report of the improved PLA technology for small-molecule detection by indirect competitive formats in the biological samples.

Effect of Cu-based metal organic framework (Cu-MOF) loaded with TiO2 on the photocatalytic degradation of rhodamine B dye.

Using copper nitrate trihydrate as the copper source, TiO2@Cu-MOF nanocomposites were prepared by a one-step crystallization method, and the effect of the amount of TiO2 loaded on the adsorption of rhodamine B was studied. X-ray diffraction (XRD), scanning electron microscope (SEM), energy spectrometer (EDS), N2 adsorption-desorption (BET), and infrared spectroscopy (FTIR) were used to characterize the microstructure and surface properties of composite materials. The results show that the composite material not only has a good degradability for rhodamine B, the decolorization rate reaches 98.03% after 120 min, but it also maintains a good cycle performance. Fitting the first-order kinetic equation to the reaction process, under the optimal conditions, R2 = 0.98, indicating that the reaction process conforms to the first-order kinetic equation. Therefore, the catalyst has good catalytic degradation and cycle performance.

Recent Advances in Binary Colloidal Crystals for Photonics and Porous Material Fabrication.

In the past few years, binary colloidal crystals (BCCs) composed of both large and small particles have attracted considerable attention from the scientific community as an exciting alternative to single colloidal crystals (SCCs). In particular, more complex structures with diverse nanotopographies and desirable optical properties of BCCs can be obtained by various colloidal assembly methods, as compared to SCCs. Furthermore, high accuracy in crystal growth with controllable stoichiometries allows for a great deal of promising applications in the fields of both interfacial and material sciences. The visible-light diffraction property of BCCs is more superior than that of SCCs, which makes them have more promising applications in the fabrication of photonic crystals with full band gaps. On the other hand, their spherical shapes and ease of removal property make them ideal templates for ordered porous material fabrication. Hence, this perspective outlined recent advances in assembly approaches of BCCs, with an emphasis on their promising applications for advanced photonics and multifunctional porous material fabrication. Eventually, some challenging yet important issues and some future perspectives are further discussed.

Magnetic graphene-based nanocomposites as highly efficient absorbents for Cr(VI) removal from wastewater.

Due to the merits of their high adsorption and convenient separation, magnetic graphene-based composites have become a promising adsorbent in terms of wastewater treatment. However, recycling and regeneration properties of magnetic graphene-based composites are still a conundrum, which remains to be resolved. Here, Fe3O4/reduced graphene oxide (RGO) (Fe3O4/RGO) nanocomposites were synthesized by one-step solvent-thermal reduction route and used as adsorbents for water purification. It was encouraging to find that the nanocomposites possessed many intriguing properties in removing of Cr(VI) ions, including high adsorption efficiency and excellent recycling and regeneration property. The results indicated that the magnetic separation process of the Fe3O4/RGO nanocomposites only took less than 5 s and the maximum removal efficiency of Cr(VI) reached 99.9% under the optimum experimental conditions. Most significantly, the adsorption rate of Cr(VI) can still be as high as 98.13% after 10 cycles and the single recycle quality of the nanocomposites can maintain at more than 80%. As a result, the Fe3O4/RGO nanocomposites could be a potential adsorbent for removing heavy metal ions effectively, especially in environmental protection and restoration.

A minireview on doped carbon dots for photocatalytic and electrocatalytic applications.

To date, carbon dots (CDs) or carbon quantum dots (CQDs), considered as alternatives to conventional fluorescent materials such as organic dyes and semiconductor quantum dots (QDs), have drawn significant attention from relevant researchers due to their superior properties, including nontoxicity, biocompatibility, low cost and facile synthesis, and high photoluminescence. In particular, doping heteroatoms with CDs can not only dramatically enhance the fluorescence but also greatly improve the electronic structure and doped CDs have been successfully applied in various technological fields. Herein, this minireview summarizes recent advances on the synthesis and optical properties of doped CDs and their promising applications for photocatalysis and electrocatalysis. Finally, some challenging issues as well as future perspectives of this exciting material are discussed.

miR-4651 inhibits cell proliferation of gingival mesenchymal stem cells by inhibiting HMGA2 under nifedipine treatment.

Drug-induced gingival overgrowth (DIGO) is recognized as a side effect of nifedipine (NIF); however, the underlying molecular mechanisms remain unknown. In this study, we found that overexpressed miR-4651 inhibits cell proliferation and induces G0/G1-phase arrest in gingival mesenchymal stem cells (GMSCs) with or without NIF treatment. Furthermore, sequential window acquisition of all theoretical mass spectra (SWATH-MS) analysis, bioinformatics analysis, and dual-luciferase report assay results confirmed that high-mobility group AT-hook 2 (HMGA2) is the downstream target gene of miR-4651. Overexpression of HMGA2 enhanced GMSC proliferation and accelerated the cell cycle with or without NIF treatment. The present study demonstrates that miR-4651 inhibits the proliferation of GMSCs and arrests the cell cycle at the G0/G1 phase by upregulating cyclin D and CDK2 while downregulating cyclin E through inhibition of HMGA2 under NIF stimulation. These findings reveal a novel mechanism regulating DIGO progression and suggest the potential of miR-4651 and HMGA2 as therapeutic targets.