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Molybdenum disulfide (MoS2) has been extensively studied as a potential storage material for batteries. However, the electrochemical performance of MoS2 is far from ideal, and it exhibits severe activity fading resulting from its low electronic conductivity. The present work synthesizes nitrogen (N)-doped 1T MoS2 nanoflowers made of ultrathin nanosheets via the one-step hydrothermal sulfurization of a molybdenum-based metal-organic framework precursor. The resulting metallic phase shows improved conductivity and hydrophilicity, and characterization demonstrates that N doping effectively expands the interlayer spacing and increases the concentration of sulfur vacancies serving as defects. This material demonstrates high rate performance and good cycling stability when used as the cathode in an aqueous rechargeable zinc-ion battery (ARZIB). Its performance is superior to those of pure 1T MoS2 and 2H MoS2 synthesized with MoO3 as the molybdenum source. Ex situ X-ray photoelectron spectroscopy and X-ray diffraction analyses are performed to explore the reaction mechanism during charging and discharging of the N-doped 1T MoS2. A three-cell series ARZIB system containing this material is used to power five light-emitting diodes to confirm the possible practical applications of this technology.

Heat shock proteins (HSPs) function as molecular chaperones and are key components responsible for protein folding, assembly, translocation, and degradation under stress conditions. However, little is known about how HSPs stabilize proteins and membranes in response to different hormonal or environmental cues in plants. Here, we combined molecular, biochemical, and genetic approaches to elucidate the involvement of cytosolic HSP70-3 in plant stress responses and the interplay between HSP70-3 and plasma membrane (PM)-localized phospholipase Dδ (PLDδ) in Arabidopsis (Arabidopsis thaliana). Analysis using pull-down, coimmunoprecipitation, and bimolecular fluorescence complementation revealed that HSP70-3 specifically interacted with PLDδ. HSP70-3 bound to microtubules, such that it stabilized cortical microtubules upon heat stress. We also showed that heat shock induced recruitment of HSP70-3 to the PM, where HSP70-3 inhibited PLDδ activity to mediate microtubule reorganization, phospholipid metabolism, and plant thermotolerance, and this process depended on the HSP70-3–PLDδ interaction. Our results suggest a model whereby the interplay between HSP70-3 and PLDδ facilitates the re-establishment of cellular homeostasis during plant responses to external stresses and reveal a regulatory mechanism in regulating membrane lipid metabolism.

This study presents a straightforward approach for the in situ polymerization of poly(N-isopropylacrylamide) (PNIPAM) chains within the one-dimensional (1D) pores of the five-coordinated zinc-based metal–organic framework DMOF in order to obtain new MOF-based composites. The loading amount of PNIPAM within DMOF ⊃ PNIPAM composites can be tuned by changing the initial weight ratio between NIPAM, which is the monomer of PNIPAM, and DMOF. The guest PNIPAM chains in the composites block partially the 1D pores of DMOF, thus leading to a narrowed nanospace. The water adsorption studies reveal that the water uptake increased by increasing the loading of PNIPAM in the final DMOF ⊃ PNIPAM composites, indicating that the exposed amide groups of PNIPAM gradually alter the hydrophobicity of pristine DMOF and lead to hydrophilic DMOF ⊃ PNIPAM composites. The composite with the highest loading of PNIPAM displays a selective adsorption for water and methanol over ethanol when using equimolar mixtures of methanol–ethanol and water–ethanol. This is confirmed by the single-component adsorption measurements as well as ideal adsorbed solution theory molecular simulations. Additionally, the water stability of pristine DMOF has been greatly improved after the incorporation of PNIPAM in its pores. PNIPAM can undergo a phase transition between hydrophobic and hydrophilic phases in response to a low temperature change. This property is used in order to control the desorption of water and methanol molecules, thus enabling an efficient and cost-effective regeneration process.

Spatiotemporal regulation of reactive oxygen species (ROS) is fine-tuned at multiple levels, including transcriptional regulation. Arabidopsis copper amine oxidase ζ (CuAOζ) is localized in peroxisomes, and the CuAOζ-derived ROS is required for indole-3-butyric acid (IBA)-induced lateral root (LR) development. Here, we showed that both GATA2 and NIGT1.2 transcription factors interacted with the 5′ untranslated region (5′ UTR) of CuAOζ, using enhanced yeast one-hybrid analysis. NIGT1.2 was highly expressed in root tips and was upregulated by IBA. Phenotypic analysis, localization, and genetic studies demonstrate that NIGT1.2 positively regulated IBA-induced CuAOζ expression, ROS generation, and LR development. Furthermore, another transcription factor, UPBEAT1 (UPB1), regulated the basal expression of CuAOζ in roots, suggesting a putative functional regulation of CuAOζ in cellular proliferation and differentiation in the root. Together, our findings indicate that transcriptional regulation of peroxisomal CuAOζ plays an important role in determining CuAOζ spatiotemporal activity and ROS homeostasis within a developing root.

This work reports a new approach for the synthesis of a zeolitic imidazolate framework (ZIF-8) composite. It employs the direct growth of the crystalline ZIF-8 on a mixed-metal oxide support TiO2 -SiO2(TSO), which mimics the porous structure of Populus nigra. Using the natural leaf as a template, the TSO support was prepared using a sol-gel method. The growth of the ZIF-8 layer on the TSO support was carried out by the seeds and second growth method. This method facilitates the homogeneous dispersion of ZIF-8 crystals at the surface of the TSO composite. The ZIF-8@TSO composite adsorbs methanol selectively, mainly due to the hierarchical porous structure of the mixed oxide support. As compared with the as-synthesized ZIF-8, a 50% methanol uptake is achieved in the ZIF-8@TSO composite, with only 25 wt % ZIF-8 loading. LAST simulations show that the ZIF-8@TSO composite has a preferential adsorption toward methanol when using an equimolar methanol-ethanol mixture. An opposite behavior is observed for the as-synthesized ZIF-8. The results show that combining MOFs and mixed-oxide supports with bioinspired structures opens opportunities for synthesizing new materials with unique and enhanced adsorption and separation properties.

Graphene-based materials have potential applications in supercapacitors, owing to their unique two-dimensional structure, high surface area, remarkable chemical stability, and outstanding electrical conductivity. In this work, Hummers method was used to prepare graphene oxide, and then in situ electrochemical method was firstly used to deposit graphene nanosheets on Co/CoO core-shell nano-structure to form a sandwich-type of Co/CoO/graphene electrode materials. The effect of electro-deposition graphene cycles on the electrochemical properties of Co/CoO/graphene composite were investigated. The results showed that the coating of graphene on Co/CoO further enhanced the conductivity of the material, and the specific capacitance reached 7.765 F cm−2 at the current density of 1 mA cm−2. The Co/CoO/graphene and AC were assembled into an asymmetric supercapacitor. After 10000 charge/discharge cycles, the total capacitance of the asymmetric supercapacitor was still maintained 79.9%. The coating of graphene not only increased the conductivity of the material, but also increased the stable of structure.

Defects caused by the structural disorder of perovskites and voltage loss resulting from mismatched band structure are important issues to address to improve the performance of carbon-based perovskite solar cells. Different from the conventional approaches of additive-based passivation of perovskite precursors and introducing a hole-transport layer between the perovskite layer and carbon electrode, herein we report a defect-healing method using phenethyl ammonium iodide (PEAI) treatment and band-structure modification using high-work-function inorganic copper phthalocyanine (CuPc). Because of its relatively smoother surfaces and lower defect content, the optimized device after PEAI-based passivation of the perovskite achieves a power conversion efficiency (PCE) of 11.74%. The PCE is further raised to 13.41% through the auxiliary energy-level matching and high hole extraction abilities of the CuPc-modified carbon electrode. The best-performing device exhibits excellent moisture tolerance and thermal stability with minor current density–voltage hysteresis.

A low-temperature carbon electrode with good perovskite compatibility is employed in hole-transport-material free perovskite solar cells, and a champion power conversion efficiency (PCE) of 11.7% is obtained. The PCE is enhanced to 14.55% by an interface modification of PEDOT:PSS. The application of this carbon on ITO/PEN substrates is also demonstrated.

This review gives an overview of the synthetic strategies used for designing metal-organic frameworks (MOFs) and MOFs-based composites studied for water-alcohol separation applications. It shows that various organic linkers, including flexible, hydrophobic and zwitterionic ligands have been used for the synthesis of MOFs with flexible frameworks, highly hydrophobic MOFs as well as MOFs with unique electronic distribution in the pores. Due to their specific structural properties, all these materials show different adsorption behavior in the presence of water and alcohols, being able to separate water-alcohol mixtures. Several studies focused on using microporous MOFs to separate water-alcohol mixtures based on the difference in the molecular size of water and alcohols. Combining MOFs with organic polymers into composites is viewed as a viable alternative to tackle some problems that powdered MOFs may cause in industrial applications. The research so far shows that MOFs embedded in polymer matrixes have led to improved efficiency and mixture permeability when comparing with the performance of pristine polymer membranes. Nevertheless, the design of membranes with high permeability, selectivity and stability is difficult due to the swelling of the polymer matrix as well as the difficulties in retaining the matrix integrity while increasing the MOF loading.

In this work, we report on the use of hydrothermal and hydrogenation processes to synthesize oxygen-deficient NiMoO4 nanoflake arrays (OD-NF) and nanowire arrays (OD-NW) for electrode applications. The introduction of oxygen vacancies into NiMoO4 increased the interlayer spacing of the crystal structure and Mo6+ in NiMoO4 was partially reduced to Mo4+. In addition to increasing the conductivity, the oxygen vacancies also promoted charge storage kinetics, while retaining the crystal structure of NiMoO4. The oxygen vacancies considerably influenced the capacitive performance of NiMoO4. Notably, OD-NF showed better electrochemical performance than that of OD-NW. Furthermore, our asymmetric supercapacitor device composed of NiMoO4 OD-NF and active carbon achieved 49.1 Wh kg−1 at a power density of 800 W kg−1 and retained a remarkable 94.2% specific capacitance after 6000 cycles.

β-Ni(OH)2 is considered a potential candidate of supercapacitor electrode material due to its high theoretical capacitance and cost efficiency. In order for β-Ni(OH)2 electrode to achieve high areal capacitances, we report effective fabrication of high mass loading low-crystalline β-Ni(OH)2 on nickel foam through the acid-etching formation of Ni3(PO4)2 precursor and the subsequent electrochemical activation. The heavily-loaded (13.5 mg cm−2), binder-free β-Ni(OH)2 electrode presents a high areal capacitance of 15.31F cm−2 (1134F g−1) at current density of 30 mA cm−2 (2.22 A g−1) and has a capacitance retention of 85% after 10,000 cycles at a high current density of 110 mA cm−2 (7.41 A g−1). Besides, the assembled hybrid supercapacitors can deliver an areal capacitance of 2.59F cm−2 at 20 mA cm−2 with a maximum energy density of 0.49 mWh cm−2 (2.45 mWh cm−3). This work provides a certain reference for exploring a low-cost and large-scale method of material synthesis at room temperature for high mass loading and capacitance in the future application.

A new series of alkaline-earth-metal based coordination polymers were synthesized by using a pyrazine-2,5-dicarboxylic acid (2,5-H2pzdc) ligand under hydrothermal conditions. These compounds show a variety of structural topologies, reflecting the variable coordination geometries of the alkaline-earth ions as well as the key role of the metal precursor salts. Ca, Sr, and Ba give porous three-dimensional compounds, namely [Ca(2,5-pzdc)(H2O)2]·H2O (1), [Sr(2,5-pzdc)(H2O)4]·H2O (3), [Ba(2,5-pzdc)(H2O)4]·2H2O (4) and [Ba(2,5pzdc)(H2O)2] (5), that feature one-dimensional hydrophilic channels which are filled with water molecules. The Sr compound retains its structure when the lattice water molecules are removed, while the other compounds undergo a structural rearrangement. The hydrophilicity of the Sr compound combined with its high stability even in the absence of guest molecules are the key characteristics that determine its good water adsorption and proton conductivity properties

ZnCo2O4 possess a high theoretical specific capacity, but low conductivity, poor stability and short cycle life hinder its practical application. In order to overcome those disadvantages of ZnCo2O4, herein, porous ZnCo2O4/Carbon (ZnCo2O4/C) core-shell nanowire arrays (NWAs) grown on Ni foam was synthesized by simple hydrothermal method and followed chemical vapor deposition. Compared with the pure ZnCo2O4, deposition of carbon offers an opportunity to significantly improve the conductivity, stability, and electrochemical performance of ZnCo2O4 NWAs. The ZnCo2O4/C electrodes deliver a high areal capacitance of 7.02 F cm−2 (2340 F g−1) and superior cycling stability of 92.6% after 10,000 cycles at 20 mA cm−2. Moreover, an asymmetric supercapacitor (ASC) was assembled with ZnCo2O4/C NWAs as the positive electrode and activated carbon (AC) as the negative electrode. The ASC device shows a high energy density of 35.75 Wh kg−1 at a power density of 73.17 W kg−1 and 73.3% of capacitance retention over 10,000 cycles. In brief, the ZnCo2O4/C NWAs are expected to be a promising material for energy storage devices of high-performance supercapacitor.

A series of water-soluble stilbazolium salts with A-π-A (A: Acceptor) model have been synthesized and fully characterized. The results obtained from absorption spectra and TD-DFT computational studies show that there is a relative strong intramolecular charge transfer (ICT) transition from pyridine unit to pyridine cation of the stilbazolium salts. Furthermore, it is found that the three stilbazolium salts (T1, T2, T3) show the strong two-photon absorption (2PA) response in the near-infrared (IR) region by Z-scan technique using femtosecond laser. And the stilbazolium salt T3 shows the largest two-photon absorption cross-section and third-order nonlinear optical (NLO) coefficient χ(3) at 730nm, indicating the different terminal substituent group of the pyridinium plays a vital role in third-order NLO behavior.

It is of great significance to develop a simple, cheap, and efficient catalyst preparation method for the development of fuel cells. Despite considerable developmental efforts have been substantial, progress has been underwhelming. To this end, a simple one-pot approach has been designed for the fabrication of Pd–Ag alloy networks (NWs) catalysts using sodium borohydride (NaBH4) as the reducing agent and cetyltrimethylammonium bromide (CTAB) as the surfactant. The electrochemical results reveal that the addition of Ag not only reduces Pd consumption but also enhances the catalytic properties of the electrocatalysts. Particularly, the current density of a Pd2Ag1 NWs-catalyzed ethylene glycol electro-oxidation reaches 1902.9 mA mg−1, which is 1.40 times higher than that for commercial Pd/C. The catalyst’s impressive performance could be attributed to its distinctive network-like structure and the promoting effect of Ag, which is in agreement with the bi-functional mechanism and a d-band electronic structure. This work is expected to have an impact for optimization of the design of high-performance Pd-based catalysts for applications in fuel cells and in the related fields.

The design of artificial photosynthetic systems (APSs) with hierarchical porosity by taking into account liquid flow and gas transport effects is of high significance. Herein we demonstrate a general and facile strategy to prepare hierarchical 1D to 3D macro/meso/nanoscopic morph-tunable g-C3N4 assemblies via bio-directed morphology engineering for enhanced artificial photosynthesis of CO and methane via CO2 reduction. Escherichia coli (1D), Papilio nephelus wings (2D, planar) and cole pollen (3D) are adopted for 1D to 3D multiscale assemblies with high surface areas via a two-step transformation process. Moreover, liquid flow and gas diffusion behaviors are investigated using COMSOL computational simulation to reveal the relationship between structural effects and output efficiency theoretically. Such methodology can be extended to realize versatile fabrication of various morph-tunable carbon nitride assemblies. Importantly, this research illustrates the power of combining theoretical calculations and experimental techniques to achieve the controlled design of high efficiency APS and may provide further avenues to APS optimization.

Interstitial (Li) and substitutional-type (Mo) co-doped new-type urchin-like Lix(Mo0.3V0.7)2O5 (LMVO) is fabricated via in situ gas bubble template strategy, which leads to distinctive conductivity, high number of active sites, reversible ion intercalation and accessible redox couple. Consequently, the electrochemical performance of LMVO is enhanced enormously owing to the hollow morphology and unique electronic structure. The charge storage capability of the synthetic LMVO is investigated in Mg2+ and Zn2+ electrolytes as well as Li+ electrolyte, due to the similar radius, higher charge, abundant reserve and rational cost. As a result, LMVO achieves a specific capacitance of 484 F g−1 at 1 A g−1 in Zn2+ electrolyte, which apparently surpasses the performance in Li+ and Mg2+ electrolytes. Moreover, the assembled LMVO//LMVO device delivers a specific capacitance of 117 F g−1 at 0.8 A g−1, which indicates large potential for application.

Creating a hybrid cobaltous-based oxide/sulfide core-shell composite is an effective strategy to improve the composites conductivity thus enhance the electrochemical performance of cobaltous oxide. By using Co3O4 nanosheets (NSs) as precursor, a room-temperature sulfurization for obtaining Co3O4/CoS core-shell NSs via anion exchange is developed which show better supercapacitor performance in contrast to the most high-temperature material process required in synthesis of CoS. The study demonstrates that the preceding step of introducing oxygen vacancies to Co3O4 by NaBH4 solution reduction is crucial, which allows S2− to facilitate entering the position of O2− in the solid phase successfully at room temperature. The as-obtained Co3O4/CoS NSs preserve the porous morphology and have larger accessible active surface area and better conductivity than those of Co3O4 and CoS composite. In this report, the Co3O4/CoS NSs exhibit an improved specific capacitance of 1658 F g−1 at 1 A g−1 which can be maintained at 92.3% after 10,000 cycles. The corresponding assembled asymmetric supercapacitor with activated carbon as anode displays a high energy density of 23.6 Wh kg−1 at a power density of 250 W kg−1.

A one dimensional nanostructure array has been considered as a successful charge transport material for perovskite solar cells (PSCs), because of its large internal surface area, superior charge collection efficiency and fast charge transport. Herein we demonstrate a ZnO nanorod (NR) array as the electron collector in a hole-conductor-free PSC with a carbon counter electrode (CE). A relatively low initial power conversion efficiency (PCE) of 5.6% was achieved using a 1 μm long ZnO NR array as an electron collector. However, by introduction of a thin TiO2 coating layer on the surface of ZnO via TiCl4 treatment, the PCE of the cell has been improved to the highest value of 8.24%. It is revealed that the performance enhancement of the ZnO/TiO2 NR based PSCs is largely attributed to the larger surface area, reduced electron combination, and superior electron transport properties.

CuO nanoarrays (CNAs) and Fe-incorporated CuO nanoarrays (FCNAs) were fabricated by hydrothermal method. Addition of Fe salt to the reaction mixture allowed the introduction of iron oxide onto the CNAs surface, which was characterized by XPS and HRTEM. Introducing Fe ion into reaction precursor significantly affected not only the morphologies of as-prepared products but also their electrochemical performance as anode for lithium ion full battery. The FCNAs electrodes showed higher specific capacity and better capacity retention at different current densities than that of CNAs.

A sandwich-structured porous supercapacitor electrode layered by MnO2/Polyaniline/MnO2 (MPM) was constructed by electrochemical deposition and in situ polymerization method. As a supercapacitor electrode, it had uniform mesoporous structure and a fast electron transport high-way due to the electrochemical deposition method and the middle thin layer of conductive polyaniline which could dramatically enhance the conductivity of MnO2. In three-electrode system, this sandwich-structured MPM electrode has superior capacitive performance to electrode which consists of only two layers of MnO2 (MM).

NiCo2S4 and carbon-NiCo2S4 hetero-structured nanosheet arrays have been firstly synthesized on nickel foams in a facile hydrothermal and CVD method. The products NiCo2S4 and carbon-NiCo2S4 are obtained in Na2S aqueous solution in a hydrothermal reaction from precursor of NiCox(OH)y and carbon-NiCo2O4 through anion exchange respectively, which are characterized by XRD, TEM, Raman analysis. The obtained binary metal sulphide NiCo2S4 nanosheet delivers better electrochemical activity and higher mass loading compared with NiCo2O4. In addition, carbon introduced enhances the capacitive behaviours and cycle performance for enhanced electric conductivity and stable architecture. The integrated carbon-NiCo2S4 electrode exhibits high areal capacitance of 8.33 F cm−2 and ultrahigh specific capacitance of 1893.2 F g−1 with a potential window of 0.8 V and high mass loading of 4.4 mg cm−2 and good cycle performance in a three-electrode system. The asymmetric supercapacitor is further assembled using carbon-NiCo2S4 as the positive electrode and activated carbon as the negative electrode. The integrated asymmetric supercapacitor demonstrates a high energy density of 68.82 Wh kg−1 at a power density of 47.83 W kg−1, which confirms its practical applicability.

A novel carbon-CoO-NiO-NiCo2O4 integrated electrode has been designed by reducing the hetero-structured NiCo2O4 nanosheet array with C2H2 on the nickel foam at a low temperature of 350 °C. The topotactical transformation from NiCo2O4 to the integrated electrode has been first conceived and investigated. Such unique nanoarchitectures exhibit excellent electrochemical performance with ultrahigh capacitance and desirable cycle life at high rates.

This paper reports a new two-step approach for growing hybrid Ni(OH) 2 /graphene structure on nickel foam for the first time. Firstly, graphene was synthesized on nickel foam, which was used both as catalyst and template, by a CVD method. Then the three-dimensional network structured Ni(OH) 2 nanosheets were deposited on the graphene-coated nickel foam by a hydrothermal method. Electrochemical tests of this kind of electrode show a high specific capacitance (1440 F/g) and excellent cycling performance of ∼100% capacitance retention over 2000 cycles in a 1 M NaOH electrolyte. The presence of the graphene is critical to the high-performance of the electrode, and the experiment using the Ni(OH) 2 on bare nickel foam exhibited a much worse cycling performance.

A series of D−A type CdIIX2L (X = Cl, Br, I) complexes with asymmetric structures were designed, synthesized and fully characterized. Structural studies indicate that Cd(II) has five-coordination with three N from terpyridine and two halides to form distorted square pyramidal complexes. The stereo-structure of the metal complexes can effectively reduce interactions between the complex molecules avoiding fluorescence quenching of the metal complexes in the solid state. The Cd(II) complexes also showed strong two-photon absorption in the near-infrared range by aperture Z-scan technique using a femtosecond laser in the solid state, with excellent two-photon absorption coefficients. The band gaps of the complexes suggested that they have potential applications in semiconductor materials and may be useful in near-IR nonlinear optical materials.

A three dimensional (3D) porous framework-like N-doped carbon (PFNC) with a high specific surface area was successfully fabricated through ammonia doping and graphitization based on pomelo peel. The obtained PFNC exhibits an enhanced specific capacitance (260 F g(-1) at 1 A g(-1)) and superior cycling performance (capacitance retention of 84.2% after 10000 cycles at 10 A g(-1)) on account of numerous voids and pores which supply sufficient pathways for ion diffusion during cycling. Furthermore, a fabricated asymmetric PFNC//PFN device based on PFNC and porous flake-like NiO (PFN) arrays achieves a specific capacitance of 88.8 F g(-1) at 0.4 A g(-1) and an energy density of 27.75 Wh kg(-1) at a power density of 300 W kg(-1) and still retains 44 F g(-1) at 10 A g(-1) and 13.75 Wh kg(-1) at power density of 7500 W kg(-1). It is important that the device is able to supply two light-emitting diodes for 25 min, which demonstrates great application potential.

In the present work, high surface area mesoporous cobalt oxide (Co 3 O 4 ) nanobelts have been synthesized by thermal treatment of cobalt hydroxide carbonate (CHC) precursors. CHC nanobelts were prepared by a facile hydrothermal method. Control experiments with variations in reaction time, solvent and different cobalt source revealed that temperature and sulfates are key factors in determining the formation of CHC nanobelts. Scanning electron microscopy and transmission electron microscopy images showed that the Co 3 O 4 nanobelts consisted of mesoporous nanobelts with the average width of 40 nm. Brunauer–Emmett–Teller (BET) gas adsorption measurement further indicated that the products presented a rather large surface area (172.09 m 2 g −1 ).

A ZnO/C core/shell structure has been synthesized using in situ CVD. A ZnO nanowire array on a Ti substrate was used as both the template and catalyst. The carbon shells form a unique wrinkled scal...

High density aligned ZnO nanotube (NT) arrays were synthesized using a facile chemical etching of electrochemically deposited ZnO nanorods (NRs). The influence of etching time and solution concentration on the ZnO NT formation was investigated. Moreover, cadmium selenide (CdSe) nanoparticles as sensitizers were assembled onto the ZnO NT and NR arrays for solar cell application. A conversion efficiency ( η ) of 0.44% was achieved for CdSe/ZnO NT-based solar cell under the white light illumination intensity of 85 mW/cm 2 . An 8% enhancement in η was observed between the CdSe/ZnO NT-based and NR-based solar cell due to the enhancement of the photocurrent density. ZnO NT arrays have been proved to have a superior ability as compared with ZnO NR arrays when employed as a semiconductor film.

One-dimensional SrSn(OH) 6 nanowires were successfully synthesized through a rapid simple method-sonochemical synthesis at room temperature without using any templates or surfactants. The growth mechanism has been proposed, and the reaction conditions were carefully investigated. The experimental results revealed that both the ultrasound irradiation and the presence of Na 2 CO 3 in the synthetic process had an impact on the fast formation of the SrSn(OH) 6 nanowires. Moreover, a subsequent precipitation-hydrothermal treatment of SrSn(OH) 6 nanowires-was conducted in ethanol at 180 °C for 8 h in order to improve their crystallinity and thermal stalibity. SrSnO 3 nanorods were converted by calcination of the hydrothermally treated SrSn(OH) 6 nanowires at 700 °C for 3 h in air. In particular, it was the first attempt to test the electrochemical properties of the SrSnO 3 products as anode in a Li ion battery. The resulting SrSnO 3 nanorods exhibited a better cyclability over 50 cycles with a reversible lithium storage capacity of 200 mA h g ―1 than that of SrSnO 3 nanoparticles.

In the present work, we report for the first time an investigation on anodic oxidation of tin in an electrolyte of dimethyl sulfoxide (DMSO)/water mixtures containing citric acid in the trans-passive region. The anodization leads to the formation of flowerlike patterns composed of tin citrate complex nanostrips on tin substrates. The products were characterized using XRD, SEM, TEM, FTIR, and XPS measurements. The formation mechanism of the tin citrate complex microstructures is discussed and the influences of the voltage, citric acid concentration, and electrolyte composition on the morphology of the microstructures were investigated. The nanostrips with a smooth surface can be transformed to polycrystalline SnO2 nanostrips with a porous structure by a thermal annealing process. This work developed a simple, clean, and effective route for fabrication of large area SnO2 nanostructured films.

Uniform crystalline MgSn(OH) 6 nanocubes were synthesized by a hydrothermal method. The influences of reaction conditions were investigated and the results showed that the solvent constituents significantly affected the shape and size of MgSn(OH) 6 ·SnO 2 /Mg 2 SnO 4 has been obtained by thermal treatment at 850 °C for 8 h under a nitrogen atmosphere using MgSn(OH) 6 as the precursor. The electrochemical tests of SnO 2 /Mg 2 SnO 4 revealed that SnO 2 /Mg 2 SnO 4 has a higher capacity and better cyclability compared to pure SnO 2 or Mg 2 SnO 4 . The electrochemical performance of SnO 2 /Mg 2 SnO 4 was sensitive to the size of the nanoparticles. The lithium-driven structural and morphological changes of the electrode after cycling were also studied by the ex-situ XRD pattern and TEM tests. This work indicates that SnO 2 /Mg 2 SnO 4 is a promising anode material candidate for application in Li-ion batteries.

Nickel hydroxyl sulfate (Ni(SO4)0.3(OH)1.4) nanobelts were obtained via a simple template-free hydrothermal reaction. The structural evolution of Ni(SO4)0.3(OH)1.4 nanobelts during ex situ heat treatment and in situ electron irradiation are investigated using transmission electron microscopy (TEM) techniques mainly including bright-field imaging, selected-area electron diffraction combined with kinematic simulations, and high-resolution TEM. The transformation from Ni(SO4)0.3(OH)1.4 to NiO can be observed in both ex situ and in situ experiments. Based on the TEM results, the structural evolution is clarified and the preliminary structural framework of Ni(SO4)0.3(OH)1.4 is proposed. This structural evolution also provides an excellent approach for large-scale production and/or modification of NiO nanoparticles.

Low-dimensional single-crystalline CdCO3 nanostructures such as nanowires, nanobelts, nanorolls, and one-dimensional (1D) hierarchical structures have been synthesized through a convenient, low-temperature hydrothermal method, and the products have been characterized by X-ray diffraction, transmission electron microscopy, field emission scanning electron microscopy, and selected area electronic diffraction. The influences of ammonia concentration, reaction time, and temperature on the morphologies of CdCO3 have been investigated. In addition, these low-dimensional nanostructures can be transformed into oriented CdO nanoporous structures through heat treatment processing, and the corresponding shapes can be preserved completely.

Objective To compare the wear of conventional ultra-high molecular weight polyethylene (CUHMWPE) and highly cross-linked polyethylene (HCLPE) in hip revision with liner exchange fixed with original locking mechanism using analysis of history medical data. Methods From Jan. 1, 2000, to Dec. 31, 2007, 26 patients (with 29 involved hips) underwent liner exchange revision fixed with the original locking mechanism due to wear of CUHMWPE and/or osteolysis. The mean age was 53 ± 9 years at the time of the primary total hip arthroplasty (THA) and 64 ± 9 years at the revision. The exchanged liners (Marathon, Depuy) were made of HCLPE. Annual X-rays were used to measure linear wear and osteolysis. The annual linear penetration was measured using PolyWare® software (Draftware Inc.). Annual Harris Hip Scores(HSS) were recorded. Results The mean follow-up time between the primary and revision THAs was 11 ± 2 years and 8 ± 2 years after revision. The mean Harris Hip Score(HHS) before primary THA, 1 year after primary THA, before revision and 1 year after revision was 43±5, 85±5, 71±6, 83±7 individually. The mean penetration of the CUHMWPE and HCLPE liners occurring in the first year were 0.44 ± 0.28 mm and 0.38 ± 0.14 mm, respectively (p = 0.211). The mean annual linear penetration of CUHMWPE and HCLPE from the second year onward were 0.29±0.09 mm and 0.08 ± 0.03 mm respectively (p

In this paper, we prepared TiO2@CdS core–shell nanorods films electrodes using a simple and low-cost chemical bath deposition method. The core–shell nanorods films electrodes were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and UV–vis spectrometry techniques. After applying these TiO2@CdS core–shell nanorods electrodes in photovoltaic cells, we found that the photocurrent was dramatically enhanced, comparing with those of bare TiO2 nanorods and CdS films electrodes. Moreover, TiO2@CdS core–shell nanorods film electrode showed better cell performance than CdS nanoparticles deposited TiO2 nanoparticles (P25) film electrode. A photocurrent of 1.31 mA/cm2, a fill factor of 0.43, an open circuit photovoltage of 0.44 V, and a conversion efficiency of 0.8% were obtained under an illumination of 32 mW/cm2, when the CdS nanoparticles deposited on TiO2 nanorods film for about 20 min. The maximum quantum efficiency of 5.0% was obtained at an incident wavelength of 500 nm. We believe that TiO2@CdS core–shell heterostructured nanorods are excellent candidates for studying some fundamental aspects on charge separation and transfer in the fields of photovoltaic cells and photocatalysis. Keywords: Core–shell, CdS, TiO2, Nanorods, Photoelectrochemical property

Antimony-doped tin oxide (ATO) suspension with monodispersion has been directly synthesized by hydrothermal method by using mixed Sb/Sn hydroxide solution as precursor, and temperature control has been used during the crystal growth. The ATO particles were characterized by XRD, TEM, SEM–EDS and resistance test. X-ray diffraction shows that all Sb ions come into the SnO 2 lattice to substitute Sn ions. The crystallinity and doping of Sb are improved through stage heating, compared with that at constantly high temperature. TEM and SEM images indicate the ATO nanoparticles are monodispersed with the size ranging from 10 to 15 nm. The process of stage heating can enhance Sb doped level and realize the synthesis of monodispersed doped oxide particles under low temperature in a short time. The possible growth mechanism is proposed.

Electrodeposition of nanoporous ZnO films and their applications to dye-sensitized solar cells (DSSCs) were investigated in the aim of developing cost-effective alternative synthetic methods and improving the ZnO-based DSSCs performance. ZnO films were grown by cathodic electrodeposition from an aqueous zinc nitrate solution containing polyvinylpyrrolidone (PVP) surfactant. PVP concentration had strong effects on the grain sizes and surface morphologies of ZnO films. Nanoporous ZnO film with grain size of 20–40 nm was obtained in the electrolyte containing 4 g/L PVP. The X-ray diffraction pattern showed that nanoporous ZnO films had a hexagonal wurtzite structure. Optical properties of such films were studied and the results indicated that the films had a band gap of 3.3 eV. DSSCs were fabricated from nanoporous ZnO films and the cell performance could be greatly improved with the increase of ZnO film thickness. The highest solar-to-electric energy conversion efficiency of 5.08% was obtained by using the electrodeposited double-layer ZnO films (8 μm thick nanoporous ZnO films on a 200 nm thick compact nanocrystalline ZnO film). The performance of such cell surpassed levels attained in previous studies on ZnO film-based DSSCs and was among the highest for DSSCs containing electrodeposited film components.

In this paper, we prepared the nanocrystalline CdS films on the indium-doped tin oxide (ITO) glass substrates using a doctor-blade technique. The source CdS powder was first prepared by a hydrothermal method and then ground into a screen-printing paste by adding ethyl cellulose as a binder and terpineol as a solvent. The CdS samples were characterized by XRD, SEM, TEM, and UV–Vis diffuse reflectance spectroscopy. A photocurrent of 3.51 mA/cm2, a fill factor of 0.44, an open circuit photovoltage of 0.50 V, and a conversion efficiency of 2.2% were obtained under a simulated solar illumination of 35 mW/cm2, when the CdS film was annealed at 380 °C in air for 30 min. The maximum quantum efficiency of 5.5% was obtained at an incident wavelength of 500 nm. Our method provides a general way to prepare electrodes of metal chalcogenide nanocrystalline films. Keywords: CdS, Doctor-blade, Hydrothermal, Nanoparticles, Photoelectrochemical property

This paper introduces the preparation of needle-shaped cuprous oxide (Cu2O) particles 3–10 nm in diameter and 40–150 nm in length on multiwall carbon nanotubes (MWNTs) by anodic oxidation of copper electrode in alkaline solution. Steady-state concentration of H2O2 as high as 0.42 mM is produced in aqueous suspension of nanosized Cu2O/MWNTs composites illuminated by simulated solar light in the presence of formate and oxygen. Assisted by Fe2+-EDTA, these photogenerated H2O2 can be used as Fenton reagent; hydroxyl radicals have been detected indirectly. The results for the degradation of brilliant red dye indicate that the effect of this new Fenton system (1 g/L nanosized Cu2O/MWNTs composites + Fe2+-EDTA + simulated sun light) can approach that of traditional Fenton system (4 mmol/L H2O2 + Fe2+-EDTA). This system is superior to the classical Fenton system in that it can act effectively for a long time.

This paper investigates electrochemical behavior of ZnO thin films deposition on transparent conducting optically glass from a simple aqueous zinc nitrate solution. At low temperature, ZnO films with grain sizes between 10 and 15 nm are obtained by controlling growth rate. The X-ray diffraction pattern shows that ZnO film has a hexagonal wurtzite structure and the preferred growth orientation is the (002) direction. Detailed X-ray photoelectron spectroscopy analysis indicates the presence of metallic Zn, OH and H 2 O species in the as prepared ZnO films. In addition, ZnO thin film changes from Zn-rich to O-rich after being annealed in air. Optical characterizations show that the films as prepared and annealed at 250 °C have high optical transmittance (> 90%) in the visible wavelength range and the band gap of the nanocrystalline ZnO films is 3.37 eV.

The grain size in cuprous oxide (Cu 2 O) thin films is a key to improve the performance of solar application devices. In this paper, electrochemical deposition of nanocrystalline Cu 2 O thin films on TiO 2 films coated on transparent conducting optically (TCO) glass substrates by cathodic reduction of cupric acetate has been investigated. The deposition kinetics of nanocrystalline Cu 2 O thin films were studied and the parameters limiting the deposition of the films were determined. Pure Cu 2 O deposited at bath temperature between 0 and 30 °C produced spherically shaped grains with 40∼50 nm diameters which have not been reported previously. The effect of pH was studied and a solution with a pH between 5.5 and 6 was found to be best. The effect of annealing on bulk structure, electrical resistivity, and optical absorption of nanocrystalline Cu 2 O thin films was also studied and the results were discussed.

A way to prepare nano-size Cu2O with electrochemical method was first reported. The nano-size TiO2–Cu2O particle composites were obtained by an electrochemical method and the properties of the composites were evaluated by high resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and diffuse reflectance UV–Vis spectroscopy (UV-DRS). The photocatalytic activities of the composites prepared by this method exceed that of Degussa P-25. Keywords: Nano-size TiO2–Cu2O particle composites, Electrochemical method, High resolution transmission electron microscopy, X-ray photoelectron spectroscopy, Diffuse reflectance UV–Vis spectroscopy

The blend system containing a poly(vinylidene fluoride/trifluoroethylene) [P(VDF/TrFE)] copolymer (68/32 mol %) and poly(vinyl acetate) (PVAc) was miscible from the results of differential scanning calorimetry (DSC) studies that exhibit the presence of a single, composition-dependent glass transition temperature (T g ) and a strong melting point depression for the semicrystalline P(VDF/TrFE) component. However, differences between the DSC and dielectric measurements, which showed a separate P(VDF/TrFE) T g peak, suggests that the P(VDF/TrFE)/PVAc blends are actually partially miscible. Because of the lower dielectric constant of PVAc and the reduced sample crystallinity caused by the addition of PVAc, both the dielectric constant and the remanent polarization of the copolymer blends decrease with increasing PVAc content. The presence of a small amount of PVAc stabilized the anomalous ferroelectric behavior of ice-water-quenched P(VDF/TrFE), and the blend portrayed normal polarization reversal behavior after adding only 1 wt % PVAc. The piezoelectric response suggests small changes with an increasing number of poling cycles. It is believed that PVAc affects the D-E hysteresis behavior at the interface between crystalline and amorphous phases, although much work remains to be done to confirm this hypothesis.

Although the biodegradation of polyurethanes (PU) by oxidative and hydrolytic agents has been studied extensively, few investigations have reported on the combination of their effects. Since neutrophils (PMN) arrive at an implanted device first and release HOCl, followed by monocyte-derived macrophages (MDM) which have potent esterase activities and oxidants of their own, the combined effect of oxidative and hydrolytic degradation on radiolabeled polycarbonate-polyurethanes (PCNU)s was investigated and compared to that of a polyester-PU (PESU) and a polyether-PU (PEU). The PCNUs were synthesized with PCN (MW = 1,000), and butanediol (14C-BD) and one of two diisocyanates, hexane-1,6-diisocyanate (14C-HDI) or methylene bis-p-phenyl diisocyanate (MDI). The PESU and PEU were synthesized using toluene-diisocyanate (14C-TDI), with polycaprolactone and polytetramethylene oxide as soft segments respectively, and ethylene diamine as the chain extender. The effect of pre-treatment with 0.1 mM HOC1 for 1 week on the HDI-based PCNUs and both TDI-based PUs resulted in a significant inhibition of radiolabel release (RR) elicited by cholesterol esterase (CE), when compared to buffer alone, whereas the MDI-based PCNU showed a small but significant increase. When PMN were activated on the HDI-based PCNU surface with phorbol myristate acetate (PMA), HOCl was released for 3 h, and was almost completely abolished by sodium azide (AZ). Simultaneously, the PMN-elicited RR, shown previously to be due to the esterolytic cleavage by serine proteases, was inhibited approximately 75% by PMA-activation of the cells, but significantly increased relative to the latter when AZ was added. Both in vitro oxidation by HOCl and the release of HOCI by PMN were associated with the inhibition of RR and suggest perturbations between oxidative and hydrolytic mechanisms of biodegradation.

The γ-ray irradiation effect on poly(vinylidene–trifluoroethylene) 80/20 mol% copolymers was studied. It is found that the irradiation results in the cross-linking in the amorphous area and the carbon–carbon double bond in the copolymer due to dehydrofluorination. The thermal analysis (DTA) data indicate that the irradiation down shifts both the melting temperature and the phase transition temperature, and the irradiation also reduces the crystallinity. It is found that the size of the crystal regions in the copolymer decreases during the irradiation and that the lattice space expanses with the irradiation. The crystal regions with a reduced size might response for the excellent electromechanical properties observed in the irradiated copolymer.

Nanobelts of nickel hydroxyl sulfate have been prepared on a large scale via a simple template-free hydrothermal reaction on the basis of a complex [Ni(NH(3))(6)](2+) formed with Ni(2+) and ammonia in an ethanol-water solution. The as-synthesized nanobelts were single crystals, with several tens of microns in length and 50-150 nm in width. The nanobelts were enclosed by top surfaces (100) and side surfaces (001) and their growth direction was parallel to [010]. The function of aqueous ammonia and ethanol was discussed. Furthermore, nanostructures of a mixture of crystralline NiO and amorphous nickel sulfate with various morphologies, such as nanobelts, porous nanobelts, and nanoparticles, were obtained by the thermal treatment of the as-synthesized Ni(SO(4))(0.3)(OH)(1.4) nanobelts at different temperatures.

Catalytic activity of cuprous oxide (Cu2O) micro-particles with cubic, octahedral, truncated-octahedral and hollow opened sphere structures for thermal decomposition of ammonium perchlorate (AP) was investigated in this paper. Cu2O with different morphologies were synthesized through one-pot hydrothermal method, which is based on the reduction of Cu(II) with d -(+)-glucose in an alkalic solvent. Morphology, crystal structure and specific surface area of final samples were characterized by using SEM, XRD, and BET, respectively. TG/DTA results show that the samples with different morphologies exhibit quite different catalytic activity in different stage of thermal decomposition of AP. Through comparing them, Cu2O micro-octahedrons with {1 1 1} facets show better catalytic effect than cubes with only {1 0 0} facets, while the Cu2O hollow microspheres enhance the high-temperature exothermic decomposition of AP significantly. The authors also discussed some underlying catalytic mechanism and offered some selection basis of catalysts in the thermal decomposition of AP.