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Constructing heterojunction is an effective way to enhance the catalytic activities of semiconductor photocatalyst owing to its special synergistic effect. In this study, a novel p-n heterostructured CdWO₄/BiOCl nanocomposites were synthesized by a facile hydrothermal and subsequently chemistry bath method. The photocatalytic performance of CdWO₄/BiOCl heterojunctions was investigated by degrading phenol and RhB under simulated solar light irradiation. Highly improved photocatalytic activities were achieved on all CdWO₄/BiOCl heterojunctions compared with both pure CdWO₄ and BiOCl. The CdWO₄/BiOCl heterojunction with optimal mole ratio of 25% CdWO₄ displayed the highest photoactivity with RhB and phenol being completely degraded in 15 min and 6 h, respectively. Mechanism analysis revealed that the interface of p-n heterojunction of CdWO₄/BiOCl composites can produce spontaneously electric field which can effectively separate photogenerated electrons and holes. Moreover, the active species research demonstrated that holes and superoxide radicals proved to be the principal active species during the photocatalytic process. This work demonstrated that the CdWO₄/BiOCl photocatalyst may be a promising material for purifying the organic contaminant in practical application.

The BiOBrxI1−x solid solutions were successfully synthesized both in water and ethylene glycol (EG), using a facile solvothermal method. The as-prepared BiOBrxI1−x solid solutions were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), UV–vis spectrometer and so on. SEM images revealed that BiOBrxI1−x solid solutions formed 2D plate-like shape in water, and formed microspheres in EG solvent; except that BiOI formed nanoparticles in EG solvent. The photocatalytic performance of all the BiOBrxI1-x solid solutions samples were investigated by degrading phenol under visible light irradiation (λ > 420 nm). The BiOBr0.5I0.5 microspheres with highly exposed {1 1 0} facets showed the highest photocatalytic activity with phenol completely degraded within 80 min under visible light irradiation. In addition, a reasonable mechanism for the enhanced photocatalytic performance was also discussed in detail.

An electrochemical palladium/ferric oxide (Pd/Fe2O3) nanocomposite modified glassy carbon electrode (GCE) was fabricated by hydrothermal method of Fe2O3 and electrochemical deposition of palladium nanoparticles, respectively. As-prepared Pd/Fe2O3 composite modified electrode exhibits enhanced electrocatalytic activity towards the catalytic oxidation of nitrite compared to Fe2O3, PdNPs modified electrodes and bare electrode. The parameters such as the influence of amount of Pd nanoparticles deposition onto the Pd/Fe2O3 modified electrode (ME) and effect of solution pH were investigated and discussed in detail. Under the optimal conditions, the Pd/Fe2O3 modified GCE can be used to detect nitrite concentration in a wide linear range of 10 and 1000 μM with the detection limit of 0.1 μM. The presence of Cu2+, Na+, Cl-, PO3-4 SO2-4, Mg2+ K+, NO-3, and NH+4 showed a trivial effect on the response of nitrite determination, revealing that developed modified electrode has an excellent anti-interference ability to common ions. It also shows good stability and reproducibility.

Herein, a novel visible-light-driven heterojunction AgI/WO3 nanocomposite was successfully prepared using a facile two-step hydrothermal-precipitation process and applied for photodegradation of organic pollutants. The information of phase structures, morphology, optical properties of the asprepared samples was analysed in detail by XRD, TEM, EDS, STEM, DRS measurement and so on. Formation of the heterostructure and intimate interactions between AgI and WO3 can promote highly effective photogenerated electron-hole pairs separation, which enable the heterojuctions to perform excellent photocatalytic activity as greatly enhanced photocatalysts compared to that of pristine AgI and WO3 for decomposing Rhodamine B (RhB) dye under visible light irradiation. In addition, the AgI/WO3 (1:1) nanocomposites exhibit optimal photocatalytic activity. Moreover, the as-prepared samples exhibit good stability, which is favorable for its potential application. Additionally, we have an analysis on a possible photocatalytic mechanism based on trapping experiments together with other experimental results.

In this paper, a series of Ag 3 PO 4 -BiOCl 1−x Br x composites with adjustable band gap has been fabricated by using a facile two-step synthetic method. The photocatalytic activity of Ag 3 PO 4 -BiOCl 1−x Br x was evaluated by photocatalytic decomposition of phenol aqueous solution under simulated solar light irradiation. The result shows that Ag 3 PO 4 -BiOCl 0.75 Br 0.25 (1:5) composite possesses the best photocatalytic activity among all the as-prepared samples. The photocatalytic activity of Ag 3 PO 4 -BiOCl can be enhanced mainly owing to the strong light absorption ability by loading Ag 3 PO 4 on the surface of BiOCl, while the photocatalytic activities of Ag 3 PO 4 -BiOCl 1−x Br x (x = 0.25, 0.5, 0.75 and 1) composites could be enhanced by restraining the recombination of photo-generated electron-hole pairs. The enhanced solar-light photocatalytic activities of Ag 3 PO 4 -BiOCl 1−x Br x composites could be ascribed to the adjustable energy band structure, which facilitates the separation of photoinduced carriers. In addition, superoxide radicals ( O 2 − ), holes (h + ) and OH are considered to dominate the photocatalytic degration process. Moreover, a possible mechanism of deep understanding on the base of experimental results was proposed.

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.

Au nanoparticles (Au NPs) were deposited onto BiOCl 1−x Br x nanosheets by using a facile ultrasonic treatment. The obtained Au-BiOCl 1−x Br x composites exhibit excellent photocatalytic property in the reaction of decomposing phenol aqueous solution under simulated solar light irradiation. There is a positive relationship exists in the surface plasmon resonance (SPR) of Au NPs and enhanced activities, which is contributed to the separation of photo-induced electrons and holes as well as facilitate the absorption of visible light. In addition, the tunable energy band structure might be beneficial to enhance the photocatalytic activities of Au-BiOCl 1−x Br x composites for optimizing the bandgap. And the OH and h + species were the main active species in photocatalytic reactions. In this paper, the Au-BiOCl 1−x Br x photocatalysts were demonstrated to be a promising material for practical applications in the purification of organic pollutants.

A series of WO 3 -BiOCl x Br 1−x heterojunctions with tunable energy band structure were successfully synthesized via a hydrothermal method. The photocatalytic activities and reaction mechanism of WO 3 -BiOCl x Br 1−x composites were investigated by decomposition of Rhodamine B (RhB). The light absorption ability, energy band structure and photocatalytic activity in WO 3 -BiOCl x Br 1−x heterojunctions could be adjusted by changing the mole ratio of Br and Cl. The results revealed that the WO 3 -BiOCl x Br 1−x composites exhibited the highest photocatalytic activities than pure WO 3 and BiOCl x Br 1−x under visible light irradiation. The photocatalytic property of WO 3 -BiOCl can be strengthened mainly owing to the enhanced light absorption ability, while the photocatalytic activities of WO 3 -BiOCl x Br 1−x (x = 0, 0.25, 0.5 and 0.75) composites could be enhanced by restricting the recombination of photo-generated electrons and holes. Among them, 5% WO 3 -BiOCl 0.25 Br 0.75 heterojunction shows the highest photocatalytic activity with RhB completely decomposed in 6 min, this can be contributed to the synergetic effects of energy band structure and light absorption ability. Moreover, the holes and superoxide radical anions were considered as the active species during photocatalytic oxidation process, and the possible mechanism of the enhancement of the photocatalytic property was proposed.

A series of heterojunction Ag 2 O/AgI photocatalysts with different Ag 2 O contents were successfully prepared though a facile two-step precipitation process at room temperature. The as-synthesized samples were measured in detail by XRD, EDS, XPS, SEM and DRS. The results showed that pherical Ag 2 O nanoparticles with diameter about 100–300 nm were uniformly distributed on the surface of AgI leading to the formation of Ag 2 O/AgI heterojunction. The photocatalytic activities of the obtained photocatalysts were evaluated by photocatalytic degradation of Rhodamine B (RhB) under visible light irradiation. The Ag 2 O/AgI with molar ratio of 1:1 showed the highest photocatalytic activities compared to the pure Ag 2 O and AgI with almost all RhB decomposed in 25 min. During photocatalytic process the visible light induced photogenerated electrons can be captured by Ag + ions on the surface lattice of heterojunction to form plasmonic Ag nanoparticles, which may promote the interfacial charge transfer. The enhanced photocatalytic activity was then largely attributed to the synergetic effects of heterojunction Ag 2 O/AgI/Ag and the efficient separation of photogenerated electron–hole pairs. This research may provide a novel Ag 2 O/AgI heterojunction with assistant of plasmonic Ag NPs to generate efficient, stable, and recyclable visible-light-driven plasmonic photocatalysts. The photocatalytic reaction kinetics and possible photocatalytic mechanism for this highly efficient photocatalysts were also proposed.

Ag nanoparticles decorated multi-walled carbon nanotubes (MWCNTs) composite was prepared by a simple electrochemical deposition approach. Transmission electron microscopy (TEM) and Energy dispersive spectroscopy (EDS) were employed to characterize the morphology and composition of the composite. The results showed that Ag nanoparticles with an average size approximately 20 nm were uniformly deposited on the MWCNTs surface. The electrochemical performance of the suggested sensor was investigated via differential pulse voltammetry (DPV) and chronoamperometry. Under optimum conditions, the AgNPs/MWCNTs/GCE displayed a rapid current response to nitrite, with the anodic peak current varying linearly with nitrite concentration in the range of 1 μM–100 μM (R = 0.9989) accompanying a low detection limit of 0.095 μM. The long-term stability and good reproducibility were also achieved on the proposed sensor. The determination of nitrite in tap water was studied and showed desirable recovery rate, signifying its possibility for practical application.

BiOCl 1− x Br x solid solutions with tunable structures and morphologies were successfully synthesized both in water and ethylene glycol (EG), via a facile solvothermal process. The microstructure and properties of composites were characterized by X-ray powder diffraction (XRD), Brunauer Emmet Teller (BET), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), UV–vis spectrophotometer, transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM) and so on. The effect on the innate character and light reaction mechanism on the photocatalytic activity of BiOCl 1− x Br x were investigated in detail by degradation of Rhodamine B (RhB). SEM revealed that rose-like BiOCl 1− x Br x solid solutions can be obtained in water and the sphere-like were synthesized in EG solvents. And the rose-like nanostructures showed superior photocatalytic properties. Furthermore, the rose-like BiOCl 0.5 Br 0.5 with high exposed {101} facets showed the highest photocatalytic activity with the RhB completely degraded within 12 min under visible light irradiation. In addition, a reasonable mechanism of the enhanced photocatalytic performance was also discussed according to the experimental results.

A novel BiIO4/Ag3PO4 nanocomposite photocatalyst was synthesized through hydrothermal and chemical precipitation methods. The as-prepared samples were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), and ultraviolet visible diffuse reflectance spectroscopy. Moreover, the photocatalytic activity was evaluated by degradation of phenol under visible light irradiation. BiIO4/Ag3PO4 nanocomposite exhibited higher photocatalytic activity than BiIO4 and Ag3PO4, with 5% BiIO4/Ag3PO4 nanocomposite displaying the highest activity. The enhanced photocatalytic performance may be due to the formation of BiIO4/Ag3PO4 heterojunction interface, which is beneficial to the separation and migration of the photogenerated electrons and holes. In addition, the active species trapping experiment demonstrated that •O2− and •OH were the major active species during the photocatalytic process.

A series of energy band adjustable Bi 2 W x Mo 1−x O 6 -BiOCl (x=0, 0.2, 0.4, 0.6, 0.8 and 1.0) heterojunctions were successfully synthesized through a solvothermal crystallization method. Characteristics and properties of the products were investigated using XRD, TEM, HRTEM, EDS, and DRS. Meanwhile, the photocatalytic activities of Bi 2 W x Mo 1−x O 6 -BiOCl composites were estimated by degrading Rhodamine B (RhB) under visible light irradiation. The results show that Bi 2 W 0.6 Mo 0.4 O 6 -BiOCl (1:14) composite displayed the best photocatalytic performance among all the as-prepared samples. The enhanced visible-light photocatalytic activities of Bi 2 W x Mo 1−x O 6 -BiOCl heterojunctions could be attributed to the generation of the adjustable energy band configuration, which has great influences on the generation of photoinduced carriers through inhibiting the recombination of electron-hole pairs. According to the active species trapping results and energy band calculation, the mechanism of the significant enhancement of the photocatalytic activity was proposed. This method may provide new insights into the energy band adjusting of photocatalysts used in environmental remediation and photocatalytic water purification.

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...

A novel AgI/AgIO3 heterojunction photocatalyst was prepared through a mild ion-exchange method at room temperature. Their photocatalytic activities were assessed by the photodegradation of rhodamine B (RhB) under simulated solar light. The AgI/AgIO3 composites performed better photocatalytic activities than pure AgI and AgIO3 with 15 % AgI/AgIO3 heterojunction showing the highest photocatalytic efficiency among all the heterojunction samples. Moreover, the 15 % AgI/AgIO3 hybrid photocatalyst also showed excellent repeatability and stability during photocatalytic reaction. The improvement of photocatalytic performance can be attributed to effective separation of photoexcited electrons and holes at the interface of AgI/AgIO3 composites. Radical trap experiments determined that the O2·− radical was the main reactive species for the photodegradation of RhB.

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.

A visible-light-driven AgI/BiOIO3 nanohybrid photocatalyst was prepared via a successive hydrothermal-deposition process. The microstructures, morphologies, and composition of the obtained photocatalysts were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), and energy-dispersive spectroscopy (EDS). The UV-vis diffuse reflectance spectrum (DRS) showed that the light absorption of the AgI/BiOIO3 nanohybrid is broadened from the UV to visible light region. The effect of AgI loading on BiOIO3 for photodegrading Rhodamine B (RhB) under visible light irradiation was investigated. The AgI/BiOIO3 nanohybrid exhibited superior photocatalytic activities to the bare AgI and BiOIO3, with the 30% AgI/BiOIO3 sample showing the highest photocatalytic degradation efficiency. Based on the energy band structure and the analysis of reactive species, the probable mechanism of enhanced photocatalytic reaction was discussed.

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.

A novel ferric oxide/multi-walled carbon nanotubes ( $$\hbox {Fe}_{2}\hbox {O}_{3}$$ /MWCNTs)-modified glassy carbon electrode (GCE) was prepared by drop casting $$\hbox {Fe}_{2}\hbox {O}_{3}$$ /MWCNTs onto the surface of GCE. Scanning electron microscopy (SEM) image shows that the $$\hbox {Fe}_{2}\hbox {O}_{3}$$ /MWCNTs has a nanostructure. Cyclic voltammetry (CV) results show that the $$\hbox {Fe}_{2}\hbox {O}_{3}$$ /MWCNTs-modified GCE presents excellent electrochemical activity in the presence of 1 mM nitrite in a 0.1 M phosphate-buffered saline (PBS) to compare the $$\hbox {Fe}_{2}\hbox {O}_{3}$$ and MWCNTs-modified GCE. Differential pulse voltammetry (DPV) results also show that the $$\hbox {Fe}_{2}\hbox {O}_{3}$$ /MWCNTs has excellent electrocatalytic performance to nitrite in a pH 7.0 PBS. The amperometric response result shows that the $$\hbox {Fe}_{2}\hbox {O}_{3}$$ /MWCNTs-modified GCE can be used to detect nitrite concentration in a wide linear range of $$10\textendash 1000\, \upmu \hbox {M}$$ with a detection limit of $$0.1\, \upmu \hbox {M}$$ .

The zinc-doped CdWO4 photocatalyst was successfully synthesized by a hydrothermal process. The influences of zinc doping on the phase structures, optical properties, morphologies and photocatalytic activities of the CdWO4 catalyst were investigated. The results showed that the zinc-doping can enhance the photocatalytic efficiency of CdWO4 with the highest activity obtained on the Zn-doped CdWO4 (Zn/Cd ratio of 0.1) for degradation of rhodamine B(RhB) under simulated solar light irradiation. The enhancement of photocatalytic activity may be attributed to the zinc doping which can change the band gap of the catalyst and subsequently inhibit the recombination of photogenerated electrons and holes.

In this study, BiOCl doped with different contents of zinc were successfully prepared via a facile ethylene glycol (EG)-assisted solvothermal process at 160 °C for 12 h. The as-synthesized samples were characterized in details by X-ray powder diffraction (XRD), energy dispersive X-ray analysis (EDS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution TEM (HRTEM), UV–vis diffuse reflectance spectra (UV–vis DRS) and Brunauer Emmet Teller (BET) measurement. The photocatalytic performances were evaluated by the photocatalytic degradation of Rhodamine B (RhB) under visible light irradiation. The results showed that Zn doping did not change the morphologies and particle sizes of BiOCl. However, it had an obvious effect on the photocurrent and BET surface area of BiOCl and accordingly the photocatalytic performance of BiOCl was greatly improved. The Zn-doped BiOCl with RZn = 0.07 showed the highest photocatalytic activities with almost all of the RhB decomposed in 8 min. Moreover, repetitive tests imply the good recyclability and stability of the catalysts. The enhanced photocatalytic activity was largely ascribed to the efficient separation of photogenerated electron–hole pairs and high BET surface area of the catalysts. In addition, a possible mechanism on basis of the experimental results was discussed.

In this study, Bi2WO6 doped with different barium contents were successfully prepared by a simple hydrothermal route at 180 °C for 12 h. The as-synthesized samples were characterized in detailed by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV–vis diffusere flectance spectroscopy (UV–vis DRS) and Brunauer–Emmet–Teller (BET) theory. Their photocatalytic activities were evaluated by photodegradation of Rhodamine B (RhB) under simulated solar light. As a result, the photocatalytic properties were enhanced after Ba doping and the Ba-doped Bi2WO6 with RBa = 0.15 showed the highest photocatalytic activities of 96.3% RhB was decomposed in 50 min. Close investigation revealed that the proper Ba doped into Bi2WO6 could not only increases its BET surface area, decrease its crystalline size, but also act as electron traps and facilitate the separation of photogenerated electron–hole pairs. The mechanism of enhanced photocatalytic activities of Ba-doped Bi2WO6 were further investigated.

A novel Fe3O4@SiO2@BiOBr photocatalyst was synthesized through a solvothermal method with the addition of core–shell Fe3O4@SiO2 nanoparticles. The results show that the photocatalyst is flower-like microspheres with diameters ranging from 2 μm to 3 μm. The as-prepared photocatalyst shows excellent photocatalytic performance in degradation of rhodamine B (RhB) under visible light irradiation (λ ≥ 420 nm) with superior stability and reusability. The introduction of the silica interlayer can suppress the direct contact of the Fe3O4 core and BiOBr to a great extent, resulting in the increased separation efficiency of the photo-induced electron–hole pairs and then higher photocatalytic performance. Furthermore, it can be completely recovered simply by applying an external magnetic field, indicating highly potential applications in wastewater treatment without secondary pollution.

In the present paper, the Co-doped Fe3O4 nanoparticles have been successfully synthesized by the co-precipitation process. The morphologies size of the Co-doped Fe3O4 nanoparticles were characterized using scanning electron microscopy (SEM). The structure of the products were characterized by Xray diffraction (XRD). The composition of the product was analyzed by energy dispersive X-ray detector (EDS). The results show that the phase structure of the Co-doped Fe3O4 nanoparticles is spinel Fe3O4 with the particle size ranging from 40 to 50 nm. The prepared Co-doped Fe3O4 nanoparticles electrode was then applied to detect hydrogen peroxide (H2O2) in 0.01 M pH 7.0 phosphate buffer medium.

In the present paper, the γ-Fe2O3 nanoparticles have been successfully synthesized by the co-precipitation process and followed by calcination. The X-ray diffraction (XRD), energy-dispersive X-ray analysis (EDS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were used to characterize the as prepared nanoparticles. The results show that the phase structure of the nanoparticles is γ-Fe2O3 with the particle size ranging from 40 to 50 nm. The catalytic activity of the γ-Fe2O3 was investigated by decomposing the phenol in liquid phase. The results showed that γ-Fe2O3 has the highest catlytic activity.

Electrochemical synthesis in a room temperature ionic liquid, 1-butyl-3-methyl-imidazolium tetrafluoroborate ([BMIBF4), has been used to prepare electrochromic poly (3-bromothiophene) (PBrT). The PBrT films were characterized by fourier-transform infrared spectroscopies (FTIR) and scanning electron microscopy (SEM). Electrochemistry properties of the prepared film was characterized by cyclic voltammetry. Spectroelectrochemistry and electrochromic properties of the PBrT films were characterized using various experiment techniques in [BMIBF4. The thin films were red at its neutral state. After oxidization of the PBrT films, the films underwent reversible change to the blue.

In the present paper, the WO3 nanoparticles were fabricated via a hydrothermal treatment. The products are characterized in detail by multiform techniques: transmission electron microscopy, X-ray diffraction. The results show that products are WO3 nanoparticles with diameter of about 100-150 nm. Electrochemistry properties of the prepared WO3 nanoparticles was characterized by cyclic voltammetry. Cyclic voltammetry results indicate that WO3 nanoparticles exhibits a remarkable electrochemical activity for hydrogen intercalation. The reason for electrochemical activity of WO3 nanoparticles is attributed to the formation of HxWO3 by hydrogen intercalation/de-intercalation into/out of the tungsten oxide.

Poly(3-methoxythiophene)/NiO (PMOT/NiO) composite films were electrochemically synthesized on a ITO surface in the ionic liquid 1-butyl-3-metyllimidazolium hexafluorophosphate ([BMIM]PF6) by a potentiodynamic polymerization method. The PMOT/NiO composite films were characterized by energy-dispersive X-ray analysis(EDS) and scanning electron microscopy (SEM). Electrochemistry properties of the prepared film was characterized by cyclic voltammetry. Spectroelectrochemistry and electrochromic properties of the PMOT/NiO composite were characterized using various experiment techniques in [BMIM]PF6.

Carbonaceous microspheres adsorbents prepared by hydrothermal process have been studied for RhB removal from aqueous solutions. Carbonaceous microspheres were characterized by scanning electron microscopy (SEM) and fourier-transform infrared spectroscopy (FTIR). It was found that there were abundant oxygen-containing functional groups on the surface of the carbonaceous microspheres. The equilibrium data of the adsorption and the effect of pH, initial pollutant concentration and temperature of solution on the adsorption of RhB by carbonaceous microspheres were studied. The carbonaceous microspheres exhibited excellent adsorption capacity for RhB.

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.

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.

The β-Ni(OH)2 nanosheets are fabricated by a hydrothermal method. The products are characterized in detail by multiform techniques: X-ray diffraction(XRD), energy-dispersive X-ray analysis(EDS), scanning electron microscopy(SEM), and transmission electron microscopy(TEM). The results show that the obtained products are nanosheets with diameters of 100-200 nm, and thickness ranging from 10nm to 15 nm . The prepared β-Ni(OH)2 nanosheets are used as electrode materials to study the electrocatalytic reduction of hydrogen peroxide (H2O2) in 0.5 M NaOH solution.

In this article, the Ag nanoparticles were synthesized on indium tin oxide conducting glass (ITO) substrate using the electrochemical deposition method. The morphology analysis of the deposits using scanning electron microscope (SEM) reveals that the sizes and densities of the Ag nanoparticles were tuned by varying the time of electrodeposition. The structure of the deposits was characterized by X-ray diffraction (XRD). The prepared Ag nanoparticles electrode was then applied to detect hydrogen peroxide (H2O2) in 0.01 M pH 7.0 phosphate buffer medium. The present electrochemical sensing platform exhibited good electrocatalytic activity towards the reduction of H2O2. The detection sensitivity of the sensor was 0.237 mA mM−1. This method is very simple, inexpensive, and undemanding, thus it should be extensively applied in many fields for the detection of H2O2.

Poly(3-methylthiophene) (PMeT) was electrochemically synthesized on an ITO surface in the ionic liquid 1-butyl-3-metyllimidazolium hexafluorophosphate ([BMIM]PF6) by a potentiodynamic polymerization method. The poly(3-methylthiophene) was characterized by fourier-transform infrared spectroscopy (FT-IR) and energy-dispersive X-ray analysis(EDS). Scanning electron microscopy (SEM) was used to show the morphology of the PMeT film. Electrochemical properties of the prepared film were characterized by cyclic voltammetry.

Mo-doped WO3 nanowires were fabricated by a hydrothermal method in the presence of K2SO4. The physical properties of prepared nanowires were characterized by X-ray diffraction (XRD), energy-dispersive X-ray analysis (EDS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results show that the obtained products are nanowires with diameters ranging between 10 and 20 nm, and lengths of about 600 nm. Its photoactivity was evaluated through the photodegradation of methylene blue (MB) in aqueous solution. Effects of the molybdenum concentration on the photoactivity of the obtained samples were investigated detailedly. The experimental results indicated that the Mo-doping enhanced the photoactivity of WO3 nanowires.

In this Article, a green chemical synthetic route was developed to synthesize Te/C nanocables by using glucose as reducing agent and carbon source, Na2TeO3 as a tellurium source, and surfactant cet...

ZnWO4 nanorods with a bundle-like structure were synthesized at 180°C for 12 h by a hydrothermal technology from Na2WO4⋅2H2O and ZnSO4⋅7H2O in the presence of sodium dodecyl sulfate (SDS). The as-synthesized bundle-like structure of ZnWO4 nanorods was characterized by various techniques: TEM, XRD and EDS. The luminescence properties of the bundle-like structure of the ZnWO4 nanorods were investigated by photoluminescence (PL) spectroscopy.

Ag/C nanocables with cross-linked structure were obtained through the reduction of Ag + with glucose in the presence of sodium dodecyl sulfate (SDS) under hydrothermal conditions. In the process, glucose acts as reducing agent and carbon source, and the final morphology of the product was determined by the SDS concentration. The formation process of nanocables included two evolution stages: the synthesis of the Ag nanowires with cross-linked structure by the SDS assistant; the carbonization of glucose and the formation of an amorphous carbon layer on Ag nanowires surface.

Dysprosium hydroxide and oxide nanorods were prepared directly from commercial bulk Dy{sub 2}O{sub 3} crystals by facile hydrothermal process at 130 and 210 deg. C, respectively. The as-synthesized dysprosium hydroxide and oxide nanorods were investigated by various techniques of XRD, TEM, SEM, and EDS. In the process, the temperature was found to play important roles in determining produce dysprosium hydroxide and oxide nanorods.

Se/C nanocables were first obtained through the reduction of Na2SeO3 with glucose in the presence of cetyltrimethylammonium bromide (CTAB) under hydrothermal conditions. In the process, glucose acts as a reducing agent and carbon source, and the final morphology of the product was determined by the CTAB concentration. The products are characterized in detail by multiform techniques: X-ray diffraction, energy-dispersive X-ray analysis, scanning electron microscopy, and transmission electron microscopy. The results show that the obtained products are coaxial nanocables with lengths of 2−6 μm, about 300−500 nm in diameter, and a surrounding sheath about 20−30 nm in thickness. It is of great importance and wide application that the obtained Se/C coaxial nanocables could be tailored freely by irradiation by an electron beam of transmission electron microscopy.

CoWO4 nanorods were synthesized at 453 K for 12 h by a hydrothermal technology from Na2WO4 · 2H2O and CoCl2 · 6H2O in the presence of sodium dodecyl sulfate (SDS). The as-synthesized CoWO4 nanorods were characterized by various techniques of X-ray diffraction, transmission electron microscopy, scanning electron microscopy, and X-ray detector. Luminescent properties of the samples were measured at room temperature. The results showed that CoWO4 products are nanorods with diameters of about 20 nm, and lengths ranging between 100 and 200 nm. CoWO4 nanorods display a very strong PL peak at 453 nm with the excitation wavelength 300 nm. The possible formation mechanism of CoWO4 nanorods was suggested.

WO 3 nanowires were fabricated by a hydrothermal method in the presence of K 2 SO 4 . The nanowires exhibit a well crystallized one-dimensional structure with 10 nm in diameter and several microns in length. Effects of other alkali salts (KNO 3 , NaNO 3 and Na 2 SO 4 ) on the morphologies of WO 3 nanocrystals were also investigated. The important role of K 2 SO 4 salt in the WO 3 nanowires synthesis has been demonstrated.

Novel cadmium-doped Bi2WO6 nanoparticles with different Cd contents have been synthesized by a one-step route using ethylene glycol and water as solvents at 180 °C for 12 h. The as-synthesized samples were characterized in detailed by SEM, XRD, EDS, HRTEM, UV–Vis DRS, BET techniques, and so on. The results shown that with the increase of the Cd2+ addition, the crystal structure, lattice space, and absorption edge were not significantly changed and the calculated band gap value was 2.58 eV. However, the flower-like Bi2WO6 sphere was gradually destroyed. Simultaneously, the surface area and photocurrent responses of the catalysts were greatly increased. Photocatalytic activity of the Cd-doped Bi2WO6 samples was determined by monitoring the change of RhB concentration under simulated solar light. The results revealed that cadmium doping greatly improved the photocatalytic efficiency of Bi2WO6. The Bi2WO6 sample with R Cd = 0.05 displayed the highest photocatalytic activity, and the degradation rate is about two times greater than pure Bi2WO6. Moreover, the Cd–Bi2WO6 photocatalyst remained stable even after five consecutive cycles. A possible mechanism of photocatalytic activity enhancement on basis of the experimental results was proposed.

MnO2 nanostructures with sea urchin shapes have been prepared by an sodium dodecyl sulfate (SDS)-assisted hydrothermal treatment method. The products were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). XRD patterns indicated that the sea urchin shaped MnO2 nanostructures were tetragonal phase. Furthermore, SEM and TEM revealed that MnO2 nanostructures with sea urchin shapes consisted of MnO2 nanorods 150−200 nm wide and several micrometers long. A growth mechanism of MnO2 nanostructures with sea urchin shapes was suggested and explained in detail.

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.

The β-Ni(OH) 2 nanosheets and nanocones are fabricated by a hydrothermal method, respectively. The products are characterized in detail by multiform techniques: X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The prepared β-Ni(OH) 2 nanosheets and nanocones are used as electrode materials to study the electrocatalytic reduction of hydrogen peroxide (H 2 O 2 ) in 0.5 M NaOH solution. The electrocatalytic activities of the β-Ni(OH) 2 for reduction of H 2 O 2 are enhanced by change of the morphology from nanocones to nanosheets. This demonstrates that β-Ni(OH) 2 nanosheets are promising cathode catalysts for fuel cells with H 2 O 2 as oxidant, which may be in place of precious metal materials.