Peng Wang

Sol-gel-derived ceramic carbon composite electrode containing isopolymolybdic anions

A new class of polyoxomelalate (POM)-modified electrodes is fabricated by the sol-gel technique and demonstrated for nitrite sensing. The electrode material comprises an interconnected dispersion of graphite powder and a uniform dispersion of isopolymolybdic anions (Mo8O26) in a porous methylsilicate matrix. The chemically modified electrodes showed well-defined cyclic voltammograms with three reversible redox couples in acidic aqueous solutions because of the good physicochemical compatibility of Mo8O26 and the carbon ceramic matrix. The Mo8O26-modified electrodes show good stability and reproducibility, especially the renewal repeatability by simple polishing in the event of surface fouling

Quaternized magnetic nanoparticles-fluorescent polymer system for detection and identification of bacteria.

Nanomaterial-based chemical nose sensor with sufficient sensing specificity is a useful analytical tool for the detection of toxicologically important substances in complicated biological systems. A sensor array containing three quaternized magnetic nanoparticles (q-MNPs)-fluorescent polymer systems has been designed to identify and quantify bacteria. The bacterial cell membranes disrupt the q-MNP-fluorescent polymer, generating unique fluorescence response array. The response intensity of the array is dependent on the level of displacement determined by the relative q-MNP-fluorescent polymer binding strength and bacteria cells-MNP interaction. These characteristic responses show a highly repeatable bacteria cells and can be differentiated by linear discriminant analysis (LDA). Based on the array response matrix from LDA, our approach has been used to measure bacteria with an accuracy of 87.5% for 10(7) cfu mL(-1) within 20 min. Combined with UV-vis measurement, the method can be successfully performed to identify and detect eight different pathogen samples with an accuracy of 96.8%. The measurement system has a potential for further applications and provides a facile and simple method for the rapid analysis of protein, DNA, and pathogens.

Selective construction of junctions on different facets of BiVO4 for enhancing photo-activity

A novel ternary Ag/BiVO4/Co3O4 hybrid photocatalyst was designed by constructing a metal–semiconductor junction and a p–n junction on electron-rich {010} facets and hole-rich {110} facets of BiVO4, respectively. The Ag/BiVO4/Co3O4 hybrid photocatalyst exhibits enhanced photocatalytic activity for rhodamine B degradation, which is over 8 times that of bare BiVO4 under simulated solar light. It was proven that the combination of a metal–semiconductor junction and a p–n junction further promotes the charge transferring across the interface, and results in an additional effect of two single junctions for improving photo-activity. This research provides a deep insight about the co-working mechanism between the two heterojunctions, and it will propose a new concept for designing a highly efficient photo-catalyst system.

A ZnO/Chitosan Composite Film: Fabrication and Anticorrosion Characterization

A composite film consisting of ZnO and Chitosan (CS) is obtained on carbon steel via cathodic electrodeposition. Optimal CS concentration of electrodeposition of ZnO/CS film is determined by the method of polarization curves. It is shown that the ZnO/CS film obtained at the concentration of 0.6 g/L has the best corrosion resistance. The deposit is studied by scanning electron microscopy (SEM), Fourier transform infrared spectra (FT-IR) and X-ray diffraction (XRD). XRD results indicate that ZnO could be fabricated by electrodeposition in composite film. FT-IR results evidence the existence of CS in composite film. SEM results demonstrate that the quality of film is improved because of the addition of CS. The anticorrosion property can be attributed to that the existence of the CS macromolecules can improve the stability of the composite film. This kind of composite film has an anticorrosion application for metal corrosion protection.

Correction: Selective construction of junctions on different facets of BiVO4 for enhancing photo-activity

Correction for ‘Selective construction of junctions on different facets of BiVO4 for enhancing photo-activity’ by Peng Wang et al., New J. Chem., 2015, 39, 9918–9925.

Aluminum Alloy Super-Hydrophobic Surface Fabrication via Electrochemical Etching Method

Electrochemical etching method was proposed to fabricate super-hydrophobic surface on 2024 aluminum alloy. The resulted surface was characterized by Field emission scanning electron microscopy (FE-SEM) and contact angle tests. It was found that the alloy modified presented super-hydrophobic property with a water contact angle of 150.3+/-3 degrees, which could be attributed to the labyrinth structure by trapping much air. The electrochemical etching method proposed is low-cost and simple. It can also find application in the fabrication of super-hydrophobic surfaces on other engineering metal and alloy surfaces.

Anodic Aluminum Oxide Matrix Encapsulating Nonivamide for Anticorrosion and Antifouling Application

Electrochemical method is applied to prepare the porous anodic aluminum oxide (AAO) membrane. After the impregnation process, nonivamide was encapsulated into the channels of the AAO membrane. We apply the electrochemical impedance spectroscopy and polarization techniques to measure the performance of the combined material. The slight solubility of nonivamide enables it to release slowly from the AAO channels. This composite AAO-nonivamide material can show multifunctional effects, anticorrosion and antifouling, to the substrate aluminum metal.