Xu Chun Song

Photocatalytic activities of Mo-doped Bi2WO6 three-dimensional hierarchical microspheres

The Mo-doped Bi(2)WO(6) three-dimensional (3D) hierarchical microspheres from nanoplates have been synthesized by a hydrothermal route. The products were characterized in detail by multiform techniques: X-ray diffraction (XRD), energy-dispersive X-ray analysis (EDS), scanning electron microscopy (SEM), and UV-vis absorption spectrum. The results of the photocatalytic degradation of Rhodamine-B (RhB) in aqueous solution showed that molybdenum ions doping greatly improved the photocatalytic efficiency of Bi(2)WO(6) 3D hierarchical microspheres. The Mo-doped Bi(2)WO(6) microspheres with atomic ratio of Mo-W of 0.05 had the best activity in photodegradation of RhB in aqueous solution under 500 W Xe lamp light irradiation.

Au nanoparticle modified carbon paper electrode for an electrocatalytic oxidation nitrite sensor

In this article, the direct electrochemical behavior of nitrite at a Au nanoparticles (AuNPs)/carbon paper (CP) electrode made using a rapid electrochemical deposition method was investigated. The morphology of the AuNPs on the CP surface was characterized by scanning electron microscopy (SEM). The existence of the Au element was verified by energy dispersive spectroscopy (EDS). The crystal structure of the AuNPs was verified by X-ray diffraction (XRD). Cyclic voltammetry (CV) was applied to evaluate the electrochemical behavior of nitrite oxidation. Under the optimum conditions, the AuNPs/CP electrode exhibited a very strong response to nitrite; the oxidation peak current linearly increased with increasing nitrite in the ranges of 1 μM to 30 μM and 40 μM to 100 μM with correlation coefficients of 0.99883 and 0.99789, and a low detection limit of 0.093 μM. The suggested sensor demonstrated high sensitivity, good reproducibility and good recovery.

Self-assembly of dandelion-like Fe3O4@C@BiOCl magnetic nanocomposites with excellent solar-driven photocatalytic properties

A dandelion-like Fe3O4@C@BiOCl magnetic nanocomposites have been successfully synthesized through a self-assembly solvothermal process. The as-prepared photocatalyst was characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy, and diffuse reflectance spectroscopy. The photocatalytic activity was evaluated on the degradation of rhodamine B under simulated solar light irradiation. It was found that the catalyst exhibited excellent photocatalytic performance with superior stability and reusability in recycling, furthermore, it could be easily recovered by applying an external magnetic field, indicating highly potential applications to avoid secondary pollution in water treatment.

The solvothermal synthesis and enhanced photocatalytic activity of Zn2+ doped BiOBr hierarchical nanostructures

Novel, visible light-induced, Zn-doped BiOBr hierarchical nanostructures were successfully prepared by solvothermal methods. The photocatalytic activity of the samples was evaluated using RhB as the target pollutant. The Zn-doped BiOBr hierarchical nanostructures exhibited significantly enhanced visible light-induced photocatalytic efficiency for the degradation of RhB compared with pure BiOBr. The Zn-doped BiOBr with RZn = 0.1 (RZn is defined as the atomic ratio of Zn to Bi) showed the highest photocatalytic activity with decolorization efficiency of almost 100% after 15 min. The enhanced photocatalytic ability could be attributed to the efficient separation of photogenerated electron–hole pairs. Moreover, the role of the active species was also evaluated by adding different scavengers during the photodegradation of RhB. A possible mechanism for the enhancement of visible light performance of Zn-doped BiOBr photocatalysts was also proposed on basis of the experimental results.

Enhanced Photocatalytic Performance of Heterojunction BiOI/BiOIO3 Nanocomposites Under Simulated Solar Light

Novel heterostructure BiOI/BiOIO3 nanocomposites were successfully prepared through a facile deposition method at room temperature. BiOIO3 is a noncentrosymmetric compound that has an internal self-built electric field. BiOI was applied as a visible light absorber to sensitize semiconductors owing to its smallest bandgap. The coupling between BiOIO3 and BiOI can combine their advantages and improve photocatalytic properties. Compared with the single BiOI and BiOIO3, the heterostructure BiOI/BiOIO3 nanocomposites displayed a significantly enhanced photocatalytic activity for the Rhodamine B (RhB) degradation. The enhanced photocatalytic performance is deduced closely related to the formation of BiOI/BiOIO3 heterojunction interface whose presence is regarded to be a favorable factor for the transfer and separation of the photogenerated electrons and holes.

Electrochemical formation and characterisation of poly(3-methylthiophene)/WO3 nanocomposite films

Stable poly(3-methylthiophene)/WO3 (PMeT/WO3) nanocomposite films have been prepared by a two-step electrochemical method. At first the WO3 film was grown by a potentiostatic method in tungsten electrolytes, and then PMeT was deposited on the WO3 film by a potentiodynamic polymerisation method in 2 M solutions of 3-methylthiophene in 1-butyl-3-metyllimidazolium hexafluorophosphate ([BMIM]PF6). The products are characterised in detail by multiform techniques: scanning electron microscopy (SEM), energy-dispersive X-ray analysis (EDS) and Fourier-transform infrared spectroscopies (FTIR). The obtained PMeT/WO3 film displays a significant enhancement of electrochemical activity and a higher stability than that of pure PMeT films.

An Innovative Electrochemical Sensor Ground on NiO Nanoparticles and Multi-Walled Carbon Nanotubes for Quantitative Determination of Nitrite

An electrochemical sensor ground on nickel oxide (NiO) nanoparticles and multi-walled carbon nanotubes (MWCNTs) was exploited for the detection of nitrite. Scanning electron microscopy (SEM) ensure the morphology of the nanocomposite consisted of NiO nanoparticle and MWCNTs. High Resolution Transmission electron microscopy (HR-TEM) reveals that the structure of NiO nanoparticles and MWCNTs. Scanning transmission electron microscopy (STEM) persuasively verified presence of the C, Ni and O element. The electrochemical character of the nanocomposite were researched by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), and the behavior of electrochemical oxidation to nitrite on NiO/MWCNTs/CP was explored by chronoamperometry. In tests, the NiO/MWCNTs/CP shown a sensitive current response toward nitrite, the oxidation peak current are linearly related to nitrite concentration in the range from 10-6 M to 10-4 M (R = 0.997) with a sensitivity of 3.53 μA μM-1 and a detection limit of 0.25 μM (S/N = 3). The validity of utilizing the proposed electrode to determine nitrite in tap water was also demonstrated.

Hydrothermal synthesis, characterisation and photocatalytic properties of BiOIO3 nanoplatelets

ABSTRACT In this work, BiOIO3 nanoplatelets were successfully prepared by a simple hydrothermal method. The as-prepared samples were characterised by energy-dispersive spectroscopy, scanning electron microscopy, high-resolution transmission electron microscopy, X-ray powder diffraction and ultraviolet visible diffuse reflectance spectroscopy. The photocatalytic activities of the as-prepared BiOIO3 nanoplatelets were evaluated by photodegradation of rhodamine B (RhB) under simulated solar light. The results showed that the change of temperature within a certain range has almost no influence on the morphology and size of BiOIO3 nanoplatelets. However, it had an obvious effect on the photocatalytic performance of BiOIO3 nanoplatelets. The results showed that the BiOIO3 sample synthesised at 130 °C exhibited the highest photocatalytic activities compared to others, with RhB completely decomposed in 80 min. The products with proper crystallinity formed at 130 °C have the optimal rate of RhB photodegradation. It indicated that the most favourable crystallinity made it beneficial to improve the photocatalytic activity. The possible mechanism of the photocatalytic reaction based on deep analysis and the experimental results was discussed in detail.

Electrochromic Properties of Co3O4/NiO Nanocomposite Films

Co3O4/NiO nanocomposite films were electrochemically synthesized on a ITO surface. The Co3O4/NiO nanocomposite films were characterized by energy-dispersive X-ray analysis (EDS) and scanning electron microscopy (SEM). The electrochromic properties of Co3O4/NiO nanocomposite films are investigated in an aqueous alkaline electrolyte (0.1M KOH) by means of transmittance, cyclic voltammetry (CV) and chronoamperometry (CA) measurements. The Co3O4/NiO nanocomposite films exhibit a noticeable electrochromism with reversible color changes, and fast switching speed (4.1 s and 3.6 s).

Electrodeposition of Poly(3-Chlorothiophene) Film on WO3 Surfaces in an Ionic Liquid

Poly(3-chlorothiophene) (PCT) was electrochemically polymerized on the surface of tungsten oxide (WO3) in the ionic liquid 1-butyl-3-metyllimidazolium hexafluorophosphate by a potentiodynamic method. The PCT/WO3 films were characterized by Fourier-transform infrared spectroscopy, scanning electron microscopy, and energy-dispersive X-ray analysis. Cyclic voltammetric experiment results showed that the electrochemical activity of the PCT/WO3 composite film was significantly improved due to the contribution of unique structure and interactions between PCT and WO3.