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Two-dimensional transition metal dichalcogenides are of particular interest in high-performance photothermal conversion, yet there remains a huge challenge in their practical application in smart textiles for healthcare, energy, and personal protection. Herein, we controllably prepared MoS2 hollow nanospheres with a high photothermal conversion efficiency of 36% via a microemulsion-hydrothermal method, which was further applied to construct photothermal fibers for personal thermal management after a hot-blast dip-drying process. Because of the prominent photothermal effect, the temperature of the photothermal fibers sharply increases from the room temperature value of 25.0 to 55.5 °C in 60 s under near-infrared illumination with a power density of 500 W/cm2. Furthermore, the photothermal fiber pad demonstrated an obvious temperature enhancement of 38.0 °C from a skin temperature of 22.0 °C after it was irradiated by natural sunlight for 60 s. Significantly, the antibacterial elimination rates of the photothermal fibers for Escherichia coli and Staphylococcus aureus are ∼99.9 and ∼99.8%, respectively. This strategy affords an avenue toward the practical application of photothermal materials in smart fibers for personal thermoregulation.

The controlled preparation of two-dimensional (2D) nanomaterials exhibiting heterojunction structures based on nontoxic and economical transition metal oxides represents breakthroughs in the electr...

Cesium tin halide (CsSnX3, where X is halogen) perovskite nanocrystals (NCs) are one of the most representative alternatives to their lead-based cousins. However, a fundamental understanding of how to regulate the growth kinetics of colloidal CsSnX3 NCs is still lacking and, specifically, the role of surfactants in affecting their growth kinetics remains incompletely understood. Here we report a general approach for colloidal synthesis of CsSnX3 perovskite NCs through a judicious combination of capping agents. We demonstrate that introducing a small amount of zwitterionic phosphatidylcholine in the reaction is of vital importance for regulating the growth kinetics of CsSnX3 NCs, which otherwise merely leads to the formation of large-sized powders. Based on a range of experimental characterization, we propose that the formation of intermediate complexes between zwitterionic phosphatidylcholine and the precursors and the steric hindrance effect of branched fatty acid side-chains of phosphatidylcholine can regulate the growth kinetics of CsSnX3, which enables us to obtain CsSnX3 NCs with emission quantum yields among the highest values ever reported. Our finding of using zwitterionic capping agents to regulate the growth kinetics may inspire more research on the synthesis of high-quality tin-based perovskite NCs that could speed up their practical applications in optoelectronic devices.

Full-spectrum photocatalysis from ultraviolet to near infrared has generated immense scientific interest in environmental purification and energy conversion, which is still a huge challenge. Herein, we utilized a solution combustion method to prepare W18O49/N-doped reduced graphene oxide (N-rGO) hybrid nanomaterials for full-spectrum photocatalytic degradation, which degraded organic dye molecules within a short reaction time (45 min) and demonstrated a high degradation rate (more than 90%) and a low initial concentration of degradation (50 mg L−1). Moreover, the relationship between irradiation light source, temperature, time, photocatalytic properties and photocatalytic mechanism of the degraded organic dye molecules have been investigated. This research afforded a full-spectrum photocatalyst for effectively removing organic dyes under any wavelength range of sunlight, whether UV, Vis or NIR light.

The rational construction of one-dimensional (1D) nanomaterials with a hierarchical structure, including multi-block, core/shell and branching structures, is a significant challenge and a crucial step toward effective control of their electrical, optical and mechanical properties. Herein, we develop a synergistic approach, integrating precipitation and microwave processes to fabricate barnyardgrass-like CuO/Cu2O heterostructure nanowires. PEG200 is an important solvent acting as a template for the formation of the barnyardgrass-like hierarchical nanostructure as well as a reductant for subsequent reduction of CuO into Cu2O via a microwave process. Furthermore, the barnyardgrass-like CuO/Cu2O heterostructure nanowires were employed as a glucose sensor with a high sensitivity of 1281 μA mM−1 cm−2, a detection limit of 16.7 μM and good stability >20 cycles. This stepwise synergistic approach opens up a new avenue for controllably synthesizing hierarchically-structured nanomaterials with excellent performance.

Cu/Cu2O/SnO2 composites were successfully prepared with a facile microwave synthesis method. The structure of Cu/Cu2O/SnO2 composite was studied by morphology characterizations, such as X-ray diffraction, transmission electron microscopy and high-resolution transmission electron microscopy, which showed that the size of the Cu/Cu2O/SnO2 particles is 20–50 nm. The synthesis mechanism revealed that SnCl4 obstructed between Cu(OH) and ethylene glycol, preventing Cu(OH) being reduced into Cu at high temperature. The photocatalytic property of Cu/Cu2O/SnO2 composite was investigated by degrading the mixed dyestuff under the irradiation of visible light at room temperature. Benefiting from the effect of electron transfer, the photocatalytic performance of the microwave-prepared Cu/Cu2O/SnO2 composite was much better than that of pure Cu2O. The possible photocatalytic mechanism of the Cu/Cu2O/SnO2 composite catalysts was proposed and elaborated in this study. This synthesis of Cu/Cu2O/SnO2 composite may provide a method for other Cu2O/semiconductor composites microwave preparation.

Bi2FeVMoO10 [(Bi0.8Fe0.4)(Mo0.4V0.4)O4] was prepared via facile co-precipitation route. It has a tetragonal Scheelite structure derived by cation substitutions in monoclinic BiVO4. Rietveld refinements of Bi2FeVMoO10 were performed in body-centered tetragonal Scheelite. The morphological property was tested via SEM, EDX, and TEM measurements. The optical property was measured by UV-vis absorption spectrum. Bi2FeVMoO10 shows a narrower band gap of 2.07 eV than the monoclinic BiVO4 and α-Bi2Mo3O12. The photo-degradation experiments of Rhodamine-B (RhB) dye solutions were conducted. Bi2FeVMoO10 nanoparticles have more efficient photocatalytic ability on RhB degradation than that of BiVO4 and α-Bi2Mo3O12. The results were discussed on the Scheelite structure characteristics such as complicated optical absorption centers, loose space in the lattice because of the vacancies, large dispersion in the CB and VB electronic components and the Fe3+/Fe2+ redox couples. This multicomponent Scheelite oxide could have potential applications in environment protection.

Hierarchical self-assembly nanomaterials with high spatial/angular precision have attracted intensive attention in the urgent research focus in industrial and environmental fields, such as the efficient removal of heavy metal ions from aqueous solution. Herein, we developed an facile microwave-induced ultrasonic hydrolysis approach for the fine synthesis of the hierarchical CuO/Cu(OH)2 urchin-like nanoparticles, which is comprised by Cu-based substructure nanowires with an average diameter of ~5 nm. Benefiting from the high specific surface area of 230.67 m2/g, the urchin-like CuO/Cu(OH)2 hierarchical nanoparticles demonstrated a high maximum adsorption capacity of 357.25 mg/g at pH = 6.0 and T = 298 K for Cr(VI). Furthermore, the corresponding removed approximately 95% can be achieved after the adsorption process for 30 min, suggesting the fast adsorption for Cr(VI). Thermodynamic and kinetic investigations revealed that the Cr(VI) adsorption on the urchin-like CuO/Cu(OH)2 hierarchical nanoparticles was an endothermic and spontaneous process, which could be well fitted by the pseudo-second-order kinetic model. This approach provides new prospects for curbing heavy metal pollution in the environment based on the hierarchical self-assembly nanomaterials.

Cu2O@Au yolk/shell structures were successfully prepared with a facile self-generated acid etching method at room temperature. The morphology is controllable by adding different amount of HAuCl4·4H2O. Scanning electron microscopy and transmission electron microscopy images showed that Au nanoparticles self-assembled into a porous shell around Cu2O core while the produced etching agent etched the core gradually and formed the cavity. The photocatalytic property of Cu2O@Au yolk/shell structures was studied by degrading MO under the irradiation of visible light at room temperature. Benefiting from the synergistic effect of cavity micro-reactor and electron transfer, the photocatalytic performance of the as-prepared Cu2O@Au yolk/shell structures was much better than that of pure Cu2O. The possible photocatalytic mechanism of the Cu2O@Au yolk/shell catalysts was proposed and elaborated in this study. It is certified that Yolk/shell structures have potential applications in photocatalysis for its active sites on the large specific area.

The bismuth molybdate oxide of Bi 14 MoO 24 (7Bi 2 O 3 ·MoO 3 ) was synthesized by the co-precipitation route. The samples developed into the uniform nanoparticles around 50 nm. Crystalline phase was verified via Rietveld XRD structural refinement. Tetragonal Bi 14 MoO 24 is related to that the face-centered cubic (fcc) δ-phase of Bi 2 O 3 -like structure. It has more loose space with a big structure-openness than parent δ-Bi 2 O 3 . The surface microstructure and components of the photocatalysts were studied by TEM, SEM, BET, EDS and XPS measurements. The UV–vis absorption spectra showed that the band gap energy of Bi 14 MoO 24 was greatly reduced in comparison with δ-Bi 2 O 3 . The result confirms that Bi 14 MoO 24 can response to visible wavelength between 200 and 500 nm ( E g = 6.2 – 2.48 eV). Bi 14 MoO 24 derived from δ-Bi 2 O 3 by incorporating Mo (7Bi 2 O 3 :MoO 3 ) in the lattices possesses broader conduction band. This greatly benefits the mobility of the light-induced charges taking part in the photocatalytic reactions. Bi 14 MoO 24 nanoparticles possess efficient photodegradation on Rhodamine B (RhB) dye and phenol solutions. The photocatalysis activities and mechanisms were discussed on the crystal structure characteristics and the measurements such as photoluminescence, exciton lifetime and XPS results. The layered Bi–O polyhedral structure, good photo-absorption, multivalent elements, quenched luminescence and long exciton lifetime were possibly the origin of its high photocatalytic activity in the photo-degradation.

Bi 3+ -containing inorganic materials usually show rich optical and electronic properties due to the hybridization between 6s and 6p electronic components together with the lone pair in Bi 3+ ions. In this work, a new semiconductor of bismuth molybdate Bi 38 Mo 7 O 78 (19Bi 2 O 3 ·7MoO 3 ) was synthesized by the sol-gel film coating and the following heat process. The samples developed into nanoparticles with average size of 40 nm. The phase formation was verified via the XRD Rietveld structural refinement. Orthorhombic Bi 38 Mo 7 O 78 can be regarded to be derived from the cubic δ-phase Bi 2 O 3 structure. The microstructure was investigated by SEM, EDX, TEM, BET and XPS measurements. The UV-vis absorption spectra showed that the band gap of Bi 38 Mo 7 O 78 (2.38 eV) was greatly narrowed in comparison with Bi 2 O 3 (2.6 eV). This enhances the efficient absorption of visible light. Meanwhile, the conduction band of is wider and shows more dispersion, which greatly benefits the mobility of the light-induced charges taking part in the photocatalytic reactions. Bi 38 Mo 7 O 78 nanoparticles possess efficient activities on the photodegradation of methylene blue (MB) solutions under the excitation of visible-light. The photocatalysis activities and mechanisms were discussed on the crystal structure characteristics and the measurements such as photoluminescence, exciton lifetime and XPS results.

Hydrangea-like silver bromide/zinc oxide (AgBr/ZnO) photocatalysts were first synthesized using a one-pot, wet chemical method, and were composed of a ZnO hierarchical structure and AgBr nanoparticles (NPs). The as-synthesized AgBr/ZnO composites were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and energy dispersive spectrometry (EDS) mapping analysis. The experimental results suggested that the AgBr NPs were uniformly decorated on the surface of the self-assembled ZnO hierarchical structure. It was found that poly vinyl pyrrolidone (PVP) and triethanolamine (TEOA) played important roles in the formation of the AgBr/ZnO hydrangea-like structure. The photocatalytic performance of AgBr/ZnO composites was then investigated using the degradation of rhodamine B under visible light irradiation. AgBr/ZnO composites exhibited better photocatalytic properties than pristine ZnO and AgBr, and the composite with 30% AgBr showed the best photocatalytic activity. The enhanced catalytic properties were attributed to the synergistic effects of the hierarchical hydrangea like structures, AgBr/ZnO heterojunction and metallic silver generated during the photocatalytic process. Therefore, the hydrangea-like AgBr/ZnO could act as a potential photocatalyst for environmental treatment and energy conversion.

A series of g-C 3 N 4 /ZnAl 2 O 4 composites were prepared using a conventional calcination method and the heterostructures were systematically characterized. It was found that the combination of g-C 3 N 4 with ZnAl 2 O 4 significantly improve their photocatalytic activities. The optimum photocatalyst of composite is at 5% (wt%) of ZnAl 2 O 4 , whose degradation efficiency for methyl orange (MO) was 96% within 120 min under visible-light irradiation. The formation of heterojunction between g-C 3 N 4 and ZnAl 2 O 4 can facilitate efficient charge separation of photogenerated electron-hole pairs, which were confirmed by electrochemical impedance spectroscopy (EIS). As a result, the photocatalytic properties of composites were enhanced.

In this work, a novel α-SnWO4/SnO2 heterostructure was synthesized via a facile two-step hydrothermal method. The as-prepared products were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scan electron microscopy (SEM) and transmission electron microscopy (TEM), which confirmed the typical orthorhombic α-SnWO4 phase, plate-like morphology and α-SnWO4/SnO2 heterostructure. The photocatalytic studies revealed that the attachment of SnO2 nanoparticles on the surface of α-SnWO4 plates can remarkably improve their photocatalytic activities and the α-SnWO4/SnO2 heterostructure exhibited the best photocatalytic properties in the degradation of methyl orange (MO) under visible light irradiation. The degradation rate of MO on α-SnWO4/SnO2 plate was 97% within 40 min and the photocatalytic degradation reaction followed the pseudo-first-order kinetics. The enhanced photocatalytic property was ascribed to the large surface area and the heterojuction between α-SnWO4 and SnO2, which can facilitate efficient charge separation of photogenerated electron–hole pairs. Furthermore, α-SnWO4/SnO2 nanocomposite demonstrated good recyclability, which is useful for its practical application.

A series of Ca 2 Sb 2 O 7 :xBi 3+ (x = 0, 0.5, 1, 1.5, 2, 4 and 8 mol%) blue phosphors were synthesized using a chemical co-precipitation technique with further calcination. The X-ray diffraction (XRD) and scanning electron microscope (SEM) results revealed that the obtained Ca 2 Sb 2 O 7 :xBi samples are orthorhombic weberite structure with particle size ranging from 20 nm to 40 nm. X-ray photoelectron spectroscopy (XPS) confirmed that the introduction of bismuth into the Ca 2 Sb 2 O 7 crystal was in the form of Bi 3+ and no other chemical states were found. The Bi-doped Ca 2 Sb 2 O 7 powders exhibit a broad emission band centered at 438 nm upon UV-irradiation and it is characterized by double-luminescence centers. The dependence of the luminescent intensity on the Bi-doping concentration in Ca 2 Sb 2 O 7 was studied in detail. As a result, the optimized concentration of Bi 3+ is 1.5 mol% for the highest emission intensity peaking at 438 nm, and the concentration quenching occurs when the concentration of Bi 3+ exceeds 1.5 mol%. The luminescence mechanism of Bi 3+ in Ca 2 Sb 2 O 7 was also discussed. The favorable luminescent properties of Ca 2 Sb 2 O 7 :Bi 3+ make it promising for lighting and display applications.

One-dimensional Cu2O nanowires were successfully prepared with a template-free microwave synthesis. Neither a surfactant was needed (to induce the growth), nor a long reaction time was required for this method. The structural investigation confirmed the successful preparation of Cu2O. The morphology images showed that the radial size of the Cu2O nanowires was 10 nm. The possible growth mechanism was hypothesized according to morphology evolution and references. A series of time-dependent experiments indicated that as time increased, Cu2O primary particles grew radially into nanowires under microwave energy irradiation. The condition-variable tests revealed that the suitable quantity of NaOH played a vital role in Cu2O nanowire formation. The photocatalytic property of the sample was investigated by degradation of methyl orange under the irradiation of visible light at room temperature. Benefiting from its unique large surface area, 4 mg of the prepared catalyst degraded 73% of methyl orange (10 mg L&minus, 1) in 120 min.

Core–shell structured Au@Cu2O nanocomposites with different morphologies were prepared by a facile solution route. X-ray diffraction (XRD) and transmission electron microscopy (TEM) results indicated that the obtained nanocomposite consisted of gold nanorod (NR) core and Cu2O shell, and both of them were in good crystallization. It was interested that the morphologies of the products could be tuned from octahedral to corner-truncated octahedral by changing the reductant. The results indicated that the reductant played a crucial role in determining the morphologies of as-prepared products. In addition, we investigated the photocatalytic properties of the products. It was found that both the core–shell structure and morphology of Au@Cu2O nanocomposites had great influence on the photodegradation of MO. As a result, the Au@Cu2O corner-truncated octahedral nanocomposites exhibited the best photocatalytic property. Our experimental results helped clarify the enhanced role of Au core and shape-dependent effect of Cu2O NPs, which contributed to pursue more efficient photocatalysts and other promising applications.

Rod-like N-doped TiO 2 /Ag composites were successfully synthesized by a modified sol–gel method, without adding any surfactants. The entire preparation differs from the traditional sol–gel synthesis of TiO 2 that the reaction can get controlled by adjusting the flow speed of water vapor and NH 3 . Characterization results show that as-prepared samples were uniform nanorods with an average length of ca. 3 µm and a cross section diameter of ca. 150 nm. The rod-like structure was formed during the annealing process. A possible mechanism was proposed to illustrate the formation of rod-like Ag–N–TiO 2 . The degradation of methylene blue performed under visible light with the prepared nanorods as the photocatalyst demonstrated the photocatalytic activities of TiO 2 can be improved by the synergistic effect of N doping and Ag modification. In addition, as-prepared TiO 2 -based photocatalyst exhibits a significantly enhanced photo-chemical stability after 5 catalytic cycles mainly due to the rod-like morphology. This indicated that they have some potential value in practical application.

CaSb 2 O 6 precursors were obtained via co-precipitation technique and subsequently they underwent calcination at different temperatures. The effect of calcination temperature on the crystallite size, specific surface area, crystallinity and defect structure of CaSb 2 O 6 has been studied in detail. It is found that the photocatalytic activity of the as-prepared CaSb 2 O 6 samples for methyl orange (MO) degradation under UV light is strongly dependent on the calcination temperature. The results demonstrated that the CaSb 2 O 6 nanoparticles calcined at 900 °C possess the best photocatalytic activity and excellent photocatalytic stability. A possible mechanism of the photocatalysis over CaSb 2 O 6 was also presented.

N-doped ZnO/Ag nanocomposites were rapidly synthesized by a deflagration method within tens of seconds, using urea as fuel and citric acid as vesicant. Characterization results showed that the samples were nanoparticles with an average size of about 15 nm. Most of Ag existed in the form of metallic Ag (0), and N was doped into the composite in the form of acceptor impurities. Compared with pure ZnO, the N-doped ZnO/Ag nanocomposites possessed a remarkably enhanced catalytic efficiency on the thermal decomposition of ammonium perchlorate. This is particularly true for the sample containing 4.0% Ag as it offered the best catalytic performance and reduced the final decomposition temperature of AP to 290 °C from 453 °C. The mechanism showed that the high decomposition rate of AP was due to N doping and Ag modification being able to transfer efficiently electrons from ClO4− to NH4+ in ammonium perchlorate.

Ag modified SnO 2 /TiO 2 nanoparticles were successfully prepared by a modified sol–gel method, without adding any acid or alkali. The entire preparation differs from the traditional sol–gel synthesis of TiO 2 that the reaction can get controlled by adjusting the flow speed of water vapor. Ultraviolet–visible diffuse reflectance spectra (UV–vis) and spin-trapping electron paramagnetic resonance (EPR) were used to forecast the photocatalytic activity of the samples, and the results were proved by the degradation of methylene blue solution under visible light. Compared with pure TiO 2 , as-prepared Ag modified SnO 2 /TiO 2 nanoparticles exhibited not only an enhanced photocatalytic activity but also an improved stability. Among all of samples, the composite with 0.5% of Ag and 1% of Sn showed the best photocatalytic performance and stability. Further increasing the Ag proportion will result in the decrease of the photocatalytic activity. A relative mechanism was proposed and discussed in detail.

AgI doped SnO2 nano-composites were prepared by the chemical coprecipitation method and were characterized by the X-ray diffraction, transmission electron microscopy and X-ray photoelectron spectroscopy. Results showed that main of the I− ions remained in the AgI lattice which is highly dispersed in the system. The photo-catalytic experiments performed under visible light irradiation using methylene blue as the pollutant revealed that not only the photo-catalytic activity but also the stability of SnO2 based photocatalyst could be improved by introduction of an appropriate amount of AgI, and the result was further supported by the UV–Vis diffuse reflection spectra and the electron spin-resonance spectra. Among all of the samples, AgI–SnO2 nano-composite with 2At% AgI exhibited the best catalytic efficiency and stability.

Au@Cu2O cuboctahedron with gold triangular nanoplate core and Cu2O shell was synthesized by a chemical method. X-ray diffraction (XRD) and transmission electron microscopy (TEM) tests demonstrated that the as-synthesis samples were consisted of gold triangular nanoplate core and Cu2O shell, and both of them were in good crystallization. The effective size control of the particles could be realized by controlling the amount of Au cores added in the synthetic process and Au@Cu2O particles with different shell thickness could be synthesized. The decrease of Cu2O shell thickness had a great difference in the optical performance, including blue shift of the resonant peaks and enhanced absorption intensity. The growth process from rough sheet structure to cuboctahedron was also explored. The results of photocatalytic degradation experiment showed that Au@Cu2O particles showed much better photocatalytic performance than that of pure Cu2O. The improved photocatalytic property of the Au@Cu2O particles was attributed to the comprehensive effect of the enhanced visible-light absorption and high separation rate of electron-hole pairs. Electronic supplementary material The online version of this article (doi:10.1186/s11671-016-1603-6) contains supplementary material, which is available to authorized users.

(a) TEM image. (b) Particle size histograms and UV-is spectra of the Au triangular nanoplate (TN) colloids. Figure S2. Photograph of colloidal suspensions of the samples. (DOCX 443Â kb)

TiO 2 /Bi 2 S 3 heterojunctions with a nuclear-shell structure were prepared by the coprecipitation method. The products were characterized by X-ray diffraction analysis, Raman spectra, transmission electron microscope images and energy dispersion X-ray spectra. Results showed that as-prepared Bi 2 S 3 was urchin-like, made from many nanorods, and TiO 2 /Bi 2 S 3 heterojunctions have a similar nuclear-shell structure, with Bi 2 S 3 as the shell and TiO 2 as the nuclear. The photocatalytic experiments performed under UV irradiation using methyl orange as the pollutant revealed that the photocatalytic activity of TiO 2 could be improved by introduction of an appropriate amount of Bi 2 S 3 . However, excessive amount of Bi 2 S 3 would result in the decrease of photocatalytic activity of TiO 2 . The relative mechanism was proposed.

The C N co-doped TiO 2 nanorods were synthesized by the vapor transport method of water molecules, and urea was used as the carbon and nitrogen source. The samples were characterized by X-ray diffraction and photoelectron spectroscopy analysis. The scanning electron microscope images showed that as-prepared TiO 2 powders were nanorods, which were formed by the stacking of nanoparticles with a uniform size around 40 nm. The degradation of methylene blue with the prepared nanorods demonstrated the photocatalytic activities of TiO 2 under visible light are improved by doping with C and N elements. The main reasons were discussed: doping with C and N elements could enhance the corresponding visible-light absorption of TiO 2 . On the other hand, doping C and N could create more oxygen vacancies in the TiO 2 crystals, which could capture the photogenerated electrons more effectively. Thus, more photogenerated holes could be left to improve the photocatalytic activity of TiO 2 .

Cubic Al 5 O 6 N nanocrystals were successfully synthesized via a novel strategy called shock wave plasma technique, using trinitrotoluene (TNT) and aluminum powder as raw materials and water as protection medium. The precursor including carbon and Al 5 O 6 N was engendered firstly during the detonation of compound dynamite, and then the pure Al 5 O 6 N nanoparticles were obtained when the carbon was removed through calcining at high temperature. The precursor and the final as-synthesized Al 5 O 6 N powder were characterized by X-ray diffraction (XRD), Raman spectrum and high-resolution transmission electron microscope (HRTEM), respectively. The calcining temperature schedule of the precursor was decided through DTA/TG analysis. The results indicate that the precursor consists of 37.7% carbon and 62.3 °C Al 5 O 6 N. After calcining at 600 °C for 1 h, the average diameter of the as-synthesized Al 5 O 6 N nanocrystal is 30–40 nm and the morphology micrograph takes on uniform spherical shape. The lattice parameters are consistent completely with the standard cubic Al 5 O 6 N (JCPDS 48-0686). The well-dispersed Al 5 O 6 N nanocrystals synthesized by shock wave plasma technique can be attributed to the covering of carbon and fast cooling of water medium. A possible reaction mechanism was also proposed preliminarily based on the experimental results.

A series of Ca2Sb2O7:xBi3+ (x = 0-8 mol%) blue phosphors is prepared by co-precipitation from a dilute HCl solution of Bi2O3, Sb2O3, and aqueous CaCl2 by adding a NaOH/Na2C2O4 solution.

We aim to design and synthesize a functional ZnO-based material with good antibacterial property and poor photocatalytic activity simultaneously and thus the textiles coated with this functional material will not prone to breed bacteria or fade. In this study, the ZnO/CaF 2 nanocomposite prepared by a homogeneous precipitation approach was selected as the candidate. Characterization results showed that as-prepared samples were uniformly distributed nanoparticles with an average size of about 30 nm. The test of antibacterial activity proved that the ZnO/CaF 2 nanocomposite can maintain the original good antibacterial property of nano-ZnO while the degradation of methylene blue under visible light revealed that CaF 2 dopant can simultaneously remarkably weaken the visible photocatalytic activity of nano-ZnO. A mechanism was proposed and discussed in detail.

Pure TiO2 and C, N co-doped TiO2 (TiO2: C, N) nanoparticles were successfully synthesized by a modified sol–gel method, using urea as the carbon and nitrogen source. The entire preparation differs from the traditional sol–gel route employed to prepare nano-TiO2 for it does not require the use of any acid or alkali. The characterization results showed that as-prepared samples were nanoparticles with a diameter of 10–30 nm. Most of the carbon incorporated in the TiO2 matrix exists in the form of elemental carbon, and nitrogen was substituted for some of the lattice oxygen atoms. The PL spectra revealed that carbon and nitrogen dopants could enhance the separation of photo-excited electrons and holes, and improve the photo-catalytic efficiency of TiO2. The conjecture was demonstrated by degrading methyl blue under visible light, using the samples as the photo-catalyst.

Hollow carbon nanospheres were prepared via a rapid detonation technique, by using negative-oxygen balance explosive trinitrotoluene and nickel powder as starting materials and inorganic acid as solvent. The carbon/metal nanocomposite particles precursor with core–shell structure was engendered firstly during detonation, and then the metal nickel core was dissolved through inorganic acid to attain the hollow carbon nanospheres. High-Resolution Transmission Electron Microscope, X-ray diffraction and Raman spectrum were used to characterize the precursor and the as-synthesized samples respectively. The results show that the external diameter of the hollow carbon nanospheres is 25–150 nm and the thickness of the wall is about 2–10 nm. The surface of hollow carbon nanosphere displays multilayer wall in structure with 0.35 nm space between the layers. Based on the experimental results, possible formation mechanism was also proposed.

As a direct bandgap semiconductor, Bi2S3has the potential ability to improve the photocatalytic activity of nano-TiO2due to its low energy gap (Eg=1.3 eV). In this study, large-scale uniform Bi2S3nanorods were synthesized by a hydrothermal treatment, using Bi[S2P(OC4H9)2]3as the single-source precursor. Characterization results show that as-prepared samples belong to an orthorhombic phase of Bi2S3, and the products mainly crystallize in the form of nanorods which measure ca. 200 nm in length and ca. 50 nm in diameter. The photo-catalytic experiments for the degradation of methyl orange under visible irradiation revealed that a small amount of as-prepared Bi2S3in our study would significantly improve the photo-catalytic activity of nano-TiO2, whether Bi2S3is introduced by a physical way or a chemical way. However, excess Bi2S3will lead to a decrease in the catalytic efficiency of TiO2when Bi2S3was introduced by a chemical way; it never happened when Bi2S3was introduced by a physical way. Even so, among all as-prepared samples, the TiO2-based photo-catalyst with 3 wt.% Bi2S3introduced by a chemical way exhibits the best catalytic performance under visible irradiation.

1.1 Plasmas technique Preparation of nano-materials can be divided into three types: gas-phase-, solid stateand liquid-methods. Material researchers have made some achievements in their own fields using different methods. Among them, the gas-phase evaporation method in vacuum is usually filled into the low-pressure inert gas interior (N2, He, Ne, Ar, etc.). Heating sources such as resistance, plasma, electron beam, laser and high frequency induction are used to make raw material gasificated or to form into plasma, which will lose energy during the collision with the inert gas atoms and then condensed into fine particles by quencher [1]. The technique of plasma plays an important role in preparing nano-materials, especially the metal particle nano-materials, which are prepared by gas-phase methods. The conception of “plasma” was first reported by Langmuir in 1927, which was firstly applied to investigate the electric discharge phenomena of mercury vapor under low pressure. Plasma is a highly ionized gas mixture, which is consists of electrons, ions, atoms and molecules. The whole system is neutral as positive and negative charges are equal. So, it has different properties from the common gases. The inner electrons, irons, and even neutral particles have higher energy, and all reactions are proceeding under high excited state. This is totally different from the typical chemical reactions, for example, in plasma the inert gas could be highly chemical active and form XeF6 and O2F2 and so on. According to the degree of gas dissociation, plasma can be divided into high-temperature plasma (high temperature can reach tens of thousands to tens of millions centigrade) and low-temperature plasma (hundreds to tens of thousands centigrade). Low temperature plasma can be divided into thermal plasma (thousands to tens of thousands centigrade) and cold plasma (hundreds centigrade). To prepare ultrafine particle by plasma, chemical reaction can take place (plasma physical method) or not (plasma chemical method).

F , C -codoped ZnO nanoparticles were synthesized by the precipitation method. X-ray photoelectron spectroscopy spectra (XPS) measurements confirmed the existence of F – Zn , C – F , – CF 2– and O – C – O bonds in the lattices of ZnO nanoparticles. The band gap of ZnO was narrowed due to F and C dopants, which should be beneficial for the improvement of the photocatalytic activity. However, our experiments demonstrated that F , C -codoping restrained the photocatalytic activity of ZnO nanoparticles. To detect the possible microstructural defects, the analysis of electron paramagnetic resonance (EPR) was performed. It was suggested that the positive-charged [Formula: see text] defects were formed by the substitution of F ions for O lattice sites. [Formula: see text] defects are deep donors and act as recombination centers for photo-generated electrons and holes, which could result in the decrease of the photocatalytic activity. Although the photocatalytic activity of F , C -codoped ZnO is depressed, the antibacterial activity still keeps a comparable level in comparison with that of pure ZnO . Therefore, this material has a potential application in textiles.

BiPO4/Bi2S3 photocatalysts were successfully synthesized by a simple two-step hydrothermal process, which involved the initial formation of BiPO4 rod and then the attachment of Bi2S3 through ion exchange. The as-synthesized products were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and UV-vis diffuse reflectance spectra (UV-vis DRS). It was found that BiPO4 was regular rods with smooth surfaces. However, BiPO4/Bi2S3 heterojunction had a rough surface, which could be attributed to the attachment of Bi2S3 on the surface of BiPO4 rods. The BiPO4/Bi2S3 composite exhibited better photocatalytic performance than that of pure BiPO4 and Bi2S3 for the degradation of methylene blue (MB) and Rhodamine B (RhB) under visible light. The enhanced photocatalytic performance could be ascribed to synergistic effect of BiPO4/Bi2S3 heterojunction, in which the attached Bi2S3 nanoparticles could improve visible-light absorption and the BiPO4/Bi2S3 heterojunction suppressed the recombination of photogenerated electron-hole pairs. Our work suggested that BiPO4/Bi2S3 heterojunction could be a potential photocatalyst under visible light.

N-doped mesoporous TiO2 nanorods were fabricated by a modified and facile sol–gel approach without any templates. Ammonium nitrate was used as a raw source of N dopants, which could produce a lot of gasses such as N2, NO2, and H2O in the process of heating samples. These gasses were proved to be vitally important to form the special mesoporous structure. The samples were characterized by the powder X-ray diffraction, X-ray photoelectron spectrometer, nitrogen adsorption isotherms, scanning electron microscopy, transmission electron microscopy, and UV-visible absorption spectra. The average length and the cross section diameter of the as-prepared samples were ca. 1.5 μm and ca. 80 nm, respectively. The photocatalytic activity was evaluated by photodegradation of methylene blue (MB) in aqueous solution. The N-doped mesoporous TiO2 nanorods showed an excellent photocatalytic activity, which may be attributed to the enlarged surface area (106.4 m2 g-1) and the narrowed band gap (2.05 eV). Besides, the rod-like photocatalyst was found to be easy to recycle.