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In recent years, as a green renewable energy production technology, electrochemical water splitting has demonstrated high development potential.

Schematic diagram of the Mn3O4/PANI nanocomposite synthesis.

The “1 + 1 > 2” synergistic antibacterial system significantly enhanced synergistic antibacterial performance, and the antibacterial efficiency against E. coli and S. aureus increases by 15% and 4.2%, respectively.

Silica aerogels with prominent physical, thermal, optical, and acoustic properties are considered to be highly promising materials. However, owing to the high cost and the complex production processes associated with existing drying technologies, the application of silica aerogels is limited in many fields. In this study, a novel combustion drying method (CDM) was successfully used in the synthesis of superhydrophobic silica aerogels for the first time. It was confirmed that silica aerogel prepared by CDM has a typical aerogel structure with low density, high porosity, high specific surface area, high total pore volume, superhydrophobicity and high thermal stability. Compared with supercritical fluid drying, freeze drying and ambient pressure drying, CDM possesses significant advantages in the drying efficiency and low-cost production due to its active drying mode. Finally, the mechanism of the combustion drying method is proposed based on the combustion of organic solvents. The results will be meaningful for the design and production of aerogel materials in the future.

Self-lubricating microcapsules containing liquid paraffin as the core material were successfully synthesized with polyurethane (PU)/silica (SiO2) as the hybrid shell material using a sol–gel proces...

NiCo layered double hydroxides (LDHs) for supercapacitors have been studied by virtue of the high specific capacitance theoretical values. However, less active sites limit the further increase of their specific capacitances. Metal-organic framework (MOF), as a promising material, has attracted intense attention with enormous specific area and adjustable structure. Herein, a practical strategy was designed to improve the active sites of the binder-free electrode by potentiostatic deposition and soaking NiCo-LDHs in 2-methylimidazole for in situ growth of MOF. This layered NiCo-MOF was obtained at room temperature which can retain more active sites to enhance capacitive properties. In particular, the prepared layered NiCo-MOF obtained a superior capacitance (1289 F g−1 at 0.5 A g−1), along with a remarkable rate capability (767 F g−1 at 20 A g−1). In addition, the as-prepared asymmetric supercapacitor exhibited a maximum specific energy of 57.8 Wh kg−1 at 748.7 W kg−1 (at a working potential of 1.5 V), and it retained 71.40% capacitance after 6000 cycles. All of these findings suggest that this work gives a practical way to synthesize NiCo-MOF nanosheets, and it exhibits excellent prospect in further energy field.

It is of great significance to develop highly active and cost-effective electrocatalysts for the oxygen evolution reaction and hydrogen evolution reaction in alkaline solution. Herein, we report an interface engineering strategy to fabricate 3D hierarchical CuCo2O4@CuCo2S4 heterostructure catalysts with efficient synergistic effects for water splitting. Owing to the special nano-architectures with abundant active interfaces, the as-prepared CuCo2O4@CuCo2S4 catalysts exhibit superior electrochemical activity and prominent electrochemical stability, with a small overpotential of 240 and 101 mV for oxygen and hydrogen evolution reactions to deliver a current density of 10 mA cm−2, respectively. Remarkably, the CuCo2O4@CuCo2S4 materials directly applied as both anode and cathode electrode demonstrate excellent water splitting performance, achieving 10 mA cm−2 at a low cell voltage of only 1.53 V, outperforming the integrated state-of-the-art RuO2||Pt/C couple (1.56 V). Moreover, density functional theory calculations suggest that the excellent overall water splitting property of CuCo2O4@CuCo2S4 is attributed to a large amount of hierarchical hetero-interfaces, giving rise to effective adsorption and cleavage of H2O molecules on the catalyst surface. This work represents a general strategy to exploit efficient and stable hybrid electrocatalysts for renewable energy applications by rational catalyst interface engineering.

Transition metal carbonates (TMCs) were studied as anode material for lithium-ion battery (LIB) by virtue of the high capacity; however, low ionic conductivity, poor electronic conductivity, and unstable cycle performances hindered their applications. Therefore, in this work, single-phase Mn1−xCoxCO3 and graphene oxide composites were synthesized by an ultrafast low temperature reaction route assisted with microwave. A high specific capacity of 1204 mA h g−1 was achieved by the composites. It also delivers 659.9 mA h g−1 after 100 cycles at 200 mA g−1 and 476 mA h g−1 after 500 cycles even at 1000 mA g−1. Such preferable electrochemical performance is caused by the synergistic effect of single-phase Mn–Co crystal structure and the functionality of graphene oxide. Therefore, it is promising to obtain mixed transition metal carbonate and graphene oxide composites through ultrafast microwave solvothermal process.

In this work, a cationic waterborne polyurethane (CWPU) dispersion containing siloxane in the side chain has been developed from 3-(2-aminoethylamino)propyldimethoxymethylsilane (APTS), using 3-dimethylamino-1,2-propanediol (DMAPD) as an ion centre. The DMAPD content was fixed constant and the effect of the APTS molar content on the particle size distribution and antibacterial performance of the CWPU dispersion, and hydrophobicity, water uptakes, crystallinity, thermal stability, surface morphology, of the forming CWPU films were wholly explored. The results indicated that more application of APTS into the CWPU might help strengthen the thermal stability and hydrophobicity for the cured films. What's more, as the molar content of APTS increased from 1% to 9%, all the CWPU dispersions reveal enhanced antibacterial activity against Escherichia coli and Staphylococcus aureus, and their maximum inhibition zone could reach 13.71 mm. This distinctly shows their great potential as antimicrobial coating materials. This work is the first in-depth study on the relationship between alkyl siloxane content and the antibacterial properties of cationic waterborne polyurethane dispersions and the resulting films.

(Tb0.5Y0.5)2O3 transparent ceramics have been prepared by wet chemical co-precipitation route and flowing H2 atmosphere sintering. The optical quality, microstructure and magneto-optical properties of the ceramics were investigated. No sintering aids or milling were adopted in the ceramic fabrication processing. The cold isostatic pressed green compact could be sintered to be transparent (Tb0.5Y0.5)2O3 ceramic at 1800 ℃ in flowing H2 atmosphere. The mechanical polished ceramic showed the good transmittance from visible to near infrared wavelength, corresponding to a 71.9% transmittance at 1400 nm wavelength. The Verdet constant measured at 632.8 nm of the (Tb0.5Y0.5)2O3 transparent ceramics was -220.19 rad T−1 m-1, which was 1.64 times that of Tb3Ga5O12 single crystal.

Super-hydrophobic films are applied in various antifouling materials such as ship and car due to their extreme water resistance. Herein, we designed and fabricated superhydrophobic waterborne fluorinated polyurethanes films containing guanidine group (WFPUs films) via one-step spray method. It was found that the guanidine and carbonyl groups of WFPUs films rapidly cross-linked by hydrogen bonds obtaining the superhydrophobic WFPUs films with appropriate surface roughness. When the amount of guanidine salt chain extender reached 11%, the water contact angle (CA) and sliding angles (SA) of WFPU4 film were 153.82° and 4.2° ± 0.9°, respectively. The surface energy was also found as 2 . The Ra (surface roughness) value of WFPUs films reduced from 26.3 nm to 5.4 nm. Moreover, upon modified with guanidine group, superhydrophobic WFPU4 film performed the mechanical durability, and the hydrophobicity of cotton was effectively enhanced. And these super-hydrophobic films containing guanidine group have potential applications in the field of environmentally friendly coatings.

Oxygen evolution reaction (OER) is considered as a critical half-cell reaction of water splitting, the kinetics of which is sluggish even not favored, thus requiring highly active electrocatalysts to shrink the reaction energy barrier and improve the energy conversion efficiency. In this study, In-situ generated trimetallic molybdate nanoflowers on Ni foam by a straightforward and time-saving solvothermal method assisted with microwave, not only bring synergistic effect into full play between multiple metals, but also construct a well-defined nanoflower-like structure accompanied by larger specific area (273.3 m2 g-1 ) and smaller size than the pristine NiMoO4 . The resulting Ni0.9 Al0.1 MoO4 -NF requires a relatively low overpotential of 266 mV for OER at 10 mA cm-2 , which outperforms commercial RuO2 catalysts (274 mV). Such excellent performance compares favorably to most previously reported NiMoO4 -based electrocatalysts for OER. This work not only supplies a facile method to construct a well-defined nanoflower-like structure on foam, but also broadens our horizons into the mechanism of OER in alkaline conditions.

A nanostructural catalyst with long-term durability under harsh conditions is very important for an outstanding catalytic performance. Herein, a new ultrastable PtCo/Co3O4-SiO2 nanocatalyst was explored to improve the catalytic performance of carbon monoxide (CO) oxidation by virtue of the surface active lattice oxygen derived from strong metal-support interactions. Such a structure can overcome the issues of Co3O4-SiO2 inactivation by water vapor and the Pt inferior activity at low temperature. Further, Co3O4-SiO2 nanosheets endow superior structure stability under high temperatures of up to 800 °C, which gives long-term catalytic cyclability of PtCo/Co3O4-SiO2 nanocomposites for CO oxidation. Moreover, the large specific surface areas (294 m2 g-1) of the nanosheet structure can expose abundant surface active lattice oxygen, which significantly enhanced the catalytic activity of CO oxidation at 50 °C over 30 days without apparent aggregation of PtCo nanoparticles after 20 cycles from 50 to 400 °C. It can be expected to be a promising candidate as an ultrastable efficient catalyst.

A nanostructural catalyst with long-term durability under harsh conditions is very important for an outstanding catalytic performance. Herein, a new ultrastable PtCo/Co

Transition metal oxalates have attracted people's attention owing to their low cost, low lithium insertion potential and high theoretical reversible capacities. Disappointingly, high irreversible capacity thanks to the formation of SEI as well as the consumption and exfoliation of active materials during the process of cycling severely restrict its application of it. In this work, a comprehensive evaluation of Co, Ni, Cu and Zn doped manganese oxalate was made. All samples are synthesized via facile and time-saving microwave hydrothermal method. It is intriguing that merely 30 min is required to accomplish the entire process and all samples possess fine electrochemical performance. As far as the four bimetallic oxalates, the resulting Mn0·5Ni0·5C2O4 exhibits the optimum performance (746.2 mA h g−1 after 100 cycles at 0.2 A g−1 and 546.7 mA h g−1 at 1 A g−1 after 400 cycles), which can be attributed to one-dimensional rod-like morphology of Mn0·5Ni0·5C2O4 as well as the synergistic and catalytic effect of Mn and Ni, resulting in faster electrode kinetics. Mn0.5Ni0.5C2O4 displays incalculable potential and can be applied in the highly reversible lithium-ion batteries.

In this paper, multiple magnetic transitions of Sm0.5Pr0.5FeO3 single crystal were systematically studied. By substituting Pr3+ in SmFeO3, spin reorientation temperature (TSR) was effectively decreased from 450 K–480 K (SmFeO3) to 180 K–220 K (Sm0.5Pr0.5FeO3). When the applied magnetic field is 500 Oe, spin switching was observed at 119 K (Tssw) for Sm0.5Pr0.5FeO3 and 180 K for SmFeO3, in which a spontaneous spin-flip transition of Sm/Pr- and Fe-sublattices at the same time, accompanied by an exchange of their FM vector directions. The compensation temperature (Tcomp) was raised from 4 K to 90 K which corresponds to zero magnetization. The possible mechanism for the modulation of magnetic transitions in SmFeO3 single crystal by Pr3+ substitution is discussed in detail. The dynamics of spin reorientation for Sm0.5Pr0.5FeO3 is also verified by Terahertz time-domain spectroscopy (THz-TDS), with the resonant excitation of quasi-antiferromagnetic (AFM) mode.

Developing high active and durable transition metal electrocatalysts would be extremely beneficial for water splitting. Here, a novel metal-organic framework assisted approach to synthesize 3D hierarchical porous NiFe-oxides nanoflowers modified with amorphous carbon network (NiFeOx@C) is reported. In the first step, NiFe-LDH-MOF nanoflowers with tunable Ni/Fe ratios are formed via facile solvothermal methods. Subsequently, a simple annealing treatment is adapted to prepare 3D hierarchical porous NiFeOx@C nanoflowers. Due to the advantages of composition, exclusive structure and synergetic effect, the as-derived porous NiFeOx@C nanoflowers catalysts exhibit small overpotential of 227 and − 186 mV for the reaction of oxygen evolution and hydrogen evolution to drive ± 10 mA cm−2, respectively. Most significantly, NiFeOx@C||NiFeOx@C water splitting electrolyzer reaches a lower cell potential of 1.59 V than that of noble metal electrolyzer RuO2||Pt/C (1.64 V) at 50 mA cm−2. Moreover, the electrocatalytic principle is investigated with particular emphasis on the synergetic effects of nickel and iron as well as active species during water splitting process. This study suggests a promising tactics for designing high active and durable bifunctional catalysts for energy conversion utilization.

Titanium dioxide (TiO2) as one of the anode materials has been studied intensively by virtue of its high safety, cheap price, environmental benignancy and high lithium insertion potential. However, the sluggish Li+ diffusivity and limited conductivity inevitably block the various applications of TiO2 in LIBs. Hence, in this work, TiO2 hierarchical hollow tubes modified with disordered carbon (HT-TiO2/C) were synthesized. The TiO2 nanoparticles of HT-TiO2/C are capable to shorten the length of Li+ diffusivity. The micro-nano structure takes both advantages of nanoscale materials (the short length of Li+ diffusivity) and micro-materials (the great structural stability). In addition, the carbon modifying layer improves the conductivity. Benefiting from the unique structural features, HT-TiO2/C shows excellent rate performance (105.5 mA h g−1 at current rate of 20 C) and distinguished long-cycle performance (88.4 mA h g−1 after 500 cycles at 20 C with a capacity retention of 88.1%).

Ultrathin two-dimensional heterogeneous structural with large specific surface area have abundant interface defects and changed surface state, which provides a mass of active sites. This novel structure can obviously enhance catalytic performance and have received researcher’s attention. Herein, a tactful way has been explored to synthesize a flower-cluster heterogenous structure NiCo/NiCoOx-SiO2 assembled by ultrathin nanobelts through coordination controlling coprecipitation in hydrothermal system followed by H2 in-situ reduction. NiCo alloy nanophase uniformly dispersed on the stable ultrathin NiCoOx-SiO2 nanobelts. Based on the favorable reactant transmission of the flower-clustered ultrathin 2D heterogeneous structure and the stabilized NiCo active sites via strong interaction with NiCoOx-SiO2, the as-obtained NiCo/NiCoOx-SiO2 nanocatalyst shows excellent stable catalytic performance, which allows over 25 recycles without obvious performance decay for the amination of p-nitrophenol and maintaining 100 % conversion even after 7 days for CO oxidation reaction at 400 °C. This work provides a new way to construct a stable, non-noble metal ultrathin heterostructure nanocatalyst with superior catalytic degradation performance of environmental pollutants for the requirement of green chemistry.

High-efficiency and stable non-precious metal electrocatalysts are of great significance to the development of the overall water splitting system in alkaline medium. Here, three-dimensional hierarchical NiFe-LDH-MOF nanoflowers with adjustable Ni/Fe ratio were synthesized by a simple hydrothermal method. Subsequently, the NiFe bimetallic based organic framework is obtained by the gas-phase anion exchanging strategy, and the corresponding phosphides MOF (NiFeP-MOF) is grown. These Ni–Fe phosphides-MOF catalysts show low potentials, small Tafel slopes, and excellent durability, accompanied by a low overpotential of 32 and 233 mV for hydrogen and oxygen evolution reactions to provide a current density of 10 mA cm−2, respectively, due to its large electrochemical surface area and 3D porous morphologies for electron and proton transfer, leading to efficient catalytic activities. It is worth noting that the symmetrical electrolyzer constructed by the NiFe-based phosphides MOFs demonstrate excellent water splitting performance, reaching a current density of 10 mA cm−2 at a relative low potential of only 1.54 V, which is superior to the precious metal RuO2||Pt/C electrocatalyst (1.57 V @ 10 mA cm−2). Density functional theory calculations prove that the outstanding overall hydrolysis of NiFeP-MOF benefits from its hierarchical porous structure, which facilitates the effective adsorption and disintegration of H2O molecule on the catalyst surface. This work provides a promising tactics to develop high efficiency electrocatalysts for practical using of overall water splitting system.

In this work, polyamidoamine (PAMAM) dendrimers are used as templates to synthesize nanotree-like polyaniline (PANI) materials, which are further used as electrode materials for supercapacitors. Effects of PAMAM content on PANIs’ structural characteristics and electrochemical properties are investigated detailedly. SEM images show that at 0.1 % PAMAM content, the PANI presents a stable self-assembled dendritic structure composed of many nanorods. Compared with pure PANI, nanotree-like PANI has better crystallinity, higher doping degree, larger high surface area and better reactivity. At a current density of 1 A g−1, the PANI nanotree electrode displays a high specific capacitance value of 812 F g−1, which is 119 % higher than that of pure PANI. Even after 1000 cycles, it still maintains about 69 % of the initial capacitance, showing good electrochemical stability. Thus the PANIs with nanotree structures are promising electrode materials for high-performance electrical energy storage devices. Moreover, the possible electrochemical enhancement mechanism of PANI nanotree electrode for supercapacitor is also discussed.

Conductive hydrogels (CHs) have attracted significant attention in wearable equipment and soft sensors due to their high flexibility and conductivity. However, CHs with high-strength and free-structure still need to be further explored. Herein, 3D printing high-strength conductive polymer hydrogels (CPHs) based on a double network was prepared. Firstly, PHEA-PSS hydrogels were prepared by copolymerizing 2-Hydroxyethyl acrylate (HEA) with 4-Vinylbenzenesulfonic acid (SSS) using a photo-curing 3D printer. Then 3, 4-Ethylenedioxythiophene (EDOT) was in situ polymerized in the network of PHEA-PSS to obtain the PHEA-PSS/PEDOT hydrogels. It can not only satisfy the printing of complex spatial structures, but also has high mechanical and electrical properties. When the content of EDOT is 12 wt%, the tensile strength of the PHEA-PSS/PEDOT hydrogels is close to 8 MPa, the electrical conductivity reach to 1.2 S cm−1 and the elasticity remain unchanged. Due to the presence of hydrogen and coordination bonds, CPHs have certain self-heal ability. In addition, the resistance of the hydrogel is sensitive to the changes of external pressure. The results show that CPHs can be used as a 3D printing material for flexible sensors.

Polypyrrole (PPy) with different morphologies (e.g., particles, nanotubes, and nanowires) were successfully prepared by adding or without adding different kinds of surfactants through a chemical oxidative polymerization method, respectively. The results show that the morphologies of PPy can be effectively controlled and have a significantly effects on their thermoelectric properties. The PPy nanowires exhibit the highest electrical conductivity and Seebeck coefficient among the various PPy morphologies, such as particles, nanotubes, and nanowires, so PPy nanowires were chosen to prepare PPy nanowire/graphene thermoelectric composites via a soft template polymerization method using cetyltrimethyl ammonium bromide as the template. Both electrical conductivity and Seebeck coefficient of the PPy nanowire/graphene composites increased as the content of graphene increases from 0 to 20 wt %, and as the measured temperature increases from 300 K to 380 K, which leds to the same trend for the power factor. A highest power factor of 1.01 &mu, Wm&minus, 1K&minus, 2 at ~380 K was obtained for the PPy nanowire/graphene composites with 20 wt % PPy nanowire, which is about 3.3 times higher than that of the pure PPy nanowire.

F-MWCNT/PANI nanocomposites was synthesized through the in-situ polymerization method in the presence of the functionized multi-walled carbon nanotubes (F-MWCNT) by though plasma treatment, and its electrochemical properties were evaluated for potential applications in supercapacitors. The results revealed that the F-MWCNT/PANI nanocomposites displays the specific capacitance as high as 546 F/g at 1.0 A/g, which is higher than MWCNT/PANI (451 F/g) and PANI (356 F/g). It also shows the good cycle stability of 76.9% capacitance retention after 1000 times cycle.

Fishbone-like PbMoO4 nanostructures are successfully obtained via the surfactant-assisted hydrothermal method at 160 ?C. Polyethylene glycol (PEG2000) is used as the template agent. The nanostructures are characterized via X-ray diffraction, field-emission scanning electron microscopy, Fourier transform infrared spectroscopy, ultraviolet-visible light (UV-Vis) spectroscopy, and photoluminescence (PL) measurements. The PbMoO4 morphology is highly associated with the molecular nature of PEG2000. PbMoO4 nanoparticles obtained from PEG2000 have a fishbone-shaped, scheelite-type tetragonal structure, in which numerous secondary branches vertically grow on both sides of the main stem. The structures exhibit broad PL emission bands with the maximum at 306 and 390 nm when excited at 250 nm. In addition, the UV-Vis absorption edge of the structures is in the 280 to 310 nm region, and the band gap is 4.07 eV. A plausible formation mechanism for the fishbone-like PbMoO4 nanostructures is also discussed.

Micrometer sized HgMoO4 flowers formed by nanorods were prepared by a selected hydrothermal method using a mixture of ethanol and water as a reaction medium, which were characterized by scanning electron microscopy, X-ray diffractometer (XRD), FT-IR spectrometry, photoluminescence spectrometry, and UV–visible spectrometry. Results indicated that the micrometer sized flowers consisted of mercury molybdate nanorods, and the monoclinic wolframite-type structure of the flowers was confirmed by both XRD and FT-IR spectrometry. A blue shift of the photoluminescence peaks and a broadening of XRD peaks were observed, which increased with ethanol fraction in the reaction medium.

In this study, carbon nanotubes (CNTs) were pretreated by plasma, and further in-situ polymerized with aniline to achieve uniform CNTs/polyaniline (PANI) composites with high conductivity. The highest conductivity (2.946 S/cm) of CNTs/PANI composites under optimum plasma treating parameters is much higher than those without CNTs pretreatment or premodified by acid oxidation method. The scanning electronic microscope (SEM) pictures indicate that smooth surfaces of pristine CNTs (diameter: 20–40 nm) changes into rough structures and the size increases to around 90 nm, which is further proved by the X-ray diffraction (XRD), the Fourier transform infrared spectroscopy (FTIR), and the Raman measurements. Thermogravimetric analysis (TGA) results reveal that the thermal stability of CNTs/PANI composite is better than that of pure PANI.

Poly(vinylidene difluoride) (PVDF)/Fe3O4 magnetic nanocomposite was prepared by a simple coprecipitation method, and was characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), and ultraviolet visible spectroscopy (UV-Vis). The SEM images showed that Fe3O4 nanoparticles were dispersed in the PVDF matrix as some aggregates with the sizes of 50 nm–2 μm, and the XRD curves showed the incorporation of the Fe3O4 nanoparticles in PVDF matrices and the decrease of the crystallinity of the PVDF. VSM results showed that the saturation magnetization (Ms) and remnant magnetization (Mr) of the PVDF/Fe3O4 nanocomposite increased with the increase of the Fe3O4 content, and that Ms and Mr along the parallel direction were higher than those along the perpendicular direction at the same Fe3O4 content. The coercive force (Hc) of the nanocomposite was independent of the Fe3O4 content and approximately equal along the parallel and perpendicular direction at the same Fe3O4 content. The optical band gap (Eg) of the PVDF/Fe3O4 nanocomposite was influenced by the Fe3O4 content, and decreased by 0.75 eV compared with that of pure PVDF when the Fe3O4 content was 3 wt %. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

In this letter, poly(vinylidene difluoride) (PVDF)/(Y0.97Eu0.03)2O3 rare-earth nanocomposites were prepared by a simple co-precipitation method, and their morphology, structure, and optical properties were investigated. The scanning electron microscope (SEM) images showed that the (Y0.97Eu0.03)2O3 rare-earth nanoparticles formed 50 nm-2 µm aggregates in PVDF matrices. X-ray diffraction (XRD) curves indicated the incorporation and structure preserving of (Y0.97Eu0.03)2O3 nanoparticles in PVDF matrices. Photoluminescence (PL) spectra of the nanocomposite showed a characteristic red light emission at 612 nm, which was attributed to the intrinsic emission of (Y0.97Eu0.03)2O3 nanoparticles. Optical band gap (Eg) of the nanocomposite exhibited a decreasing trend with the increase of (Y0.97Eu0.03)2O3 content in PVDF matrices within the experimental dosage range.

As a new nanomaterial, HgWO 4 nanofilms are prepared by the self-inventive technique of collodion nanoparticles-dispersal and film-formation. Their photoluminescent properties are enhanced and then controlled through nano- TiO 2 doping. These approaches not only ensure film uniformity and fluorescence (FL) enhancement, but also realize a FL increase/decrease conversion effect. The relationships between HgWO 4 nanofilms' PL intensities and TiO 2 doped amounts are in good agreement with Gaussion function, and maximum PL intensities of HgWO 4 nanofilms are located at 3.8% ratio of TiO 2 nanoparticles.

CdS hollow/solid nanospheres and their chain-structures were successfully synthesized through supporting liquid membrane (SLM) system with bio-membrane. X-ray powder diffraction (XRD), transmission electron microscopy (TEM), UV–Vis spectroscopy, and photoluminescence (PL) spectroscopy have been used for the characterization of the products. The average diameters of CdS solid/hollow spheres are about 10, 40 nm, respectively. The wall of the hollow spheres is about 5 nm. CdS products are all cubic face-centered structure with the cell constant a = 5.830 A. We also explore the morphology, structure and possible synthesis mechanism. A possible template mechanism has been proposed for the production of the hollow CdS nanocrystals, that is, CdS nanoparticles grow along the non-soakage interface between CHCl3 and reactant solution. During this process, the organic functional groups were crucial to the control of crystal morphologies.

ZnWO4–TiO2 composite nanofilms on a glass slide were prepared by means of the dip-coating method, in which collodion was used as a dispersant and film-forming agent. The nanofilms are characterized through SEM, XRD, TG/DTA, PL and IR, respectively. SEM and XRD characterization of these films indicated that ZnWO4 and TiO2 particles crystallized in a monoclinic wolframite-type structure and Anatase phase, respectively, and both of these were well dispersed in the nanofilms. Compared with nanoparticles, when TiO2 nanoparticles were added in 3.61% ratio, the PL intensities of ZnWO4 nanofilms were obviously enhanced. FTIR spectra further confirmed the presence of ZnWO4 on the nanofilms.

For the first time, a newly luminescent nanomaterial, monoclinic wolframite-type HgWO4 nanorods (diameter: ∼200 nm; length: ~2000 nm) are prepared by hydrothermal method together with ultrasonic technique. Fluorescent (FL) and UV–Vis results both show that for HgWO4, ultrasonic irradiation procedure will change its optical behaviors greatly. When the crystals become into nanorods, the fluorescent emitting peaks (365 and 495 nm) shift to central region, and finally form a wider one at 435 nm. Similar results of UV–visible absorption peaks are observed for these two products. FTIR spectra further characterize their structure. All above unique optical performances might result from both small sizes caused by ultrasonic irradiation procedure and involvement of incompact d10 electrons. Moreover, possible synthesis mechanisms of HgWO4 nanorods are also investigated.

For the first time, a novel route for preparing AWO4 (A=Zn, Cd) nanofilm on a glass substrate is proposed through the combination of reverse micelle system with dip-coating technology. Here collodion is used as a dispersant and film-forming agent to obtain nanofilm with a good quality and property. SEM and XRD results indicate ZnWO4 and CdWO4 nanoparticles with monoclinic system and wolframite structure are well dispersed on the substrate. The nanofilm’s photoluminescent(PL) bands obviously blue shift compared with bulk materials whereas red shift compared with nanoparticles, which should be due to quantum size effect and film-forming effect. FTIR absorption bands between 400 and 900 cm−1 prove the presence of ZnWO4 or CdWO4 nanoparticles on the substrate.