棒状V_(3)O_(7)•H_(2)O电极材料的制备及印刷超级电容器

以V2O5为原料,利用溶剂热法一步制备了V_(3)O_(7)•H_(2)O纳米棒,采用SEM、XRD、EDS、XPS和FTIR对样品进行了测试。以V_(3)O_(7)•H_(2)O纳米棒为电极材料,探究了丝网印刷工艺对电极电化学性能的影响,将此电极组装超级电容器并评价了其电化学性能。结果表明,丝网印刷电极比电容可达268.0 F/g(电流密度为0.3 A/g),经过5000次循环后电容保持率为85.9%,优于涂抹电极的比电容(246.0 F/g)和电容保持率(68.0%),这得益于丝网印刷的油墨规则排列的结构。组装的纽扣超级电容器也表现出优异的电化学性能,比电容和电容保持率为134.2 F/g(0.5 A/g电流密度)和91.2%(5000次充放电循环),且当能量密度为22.0 W·h/kg时,功率密度最高可达4125.0 W/kg。

Growth of β-Ga_2O_3 nanorods by ammoniating Ga_2O_3/V thin films on Si substrate

This paper reports that/3-Ga2O3 nanorods have been synthesized by ammoniating Ga2O3 films on a V middle layer deposited on Si（111） substrates. The synthesized nanorods were confirmed as monoclinic Ga2O3 by x-ray diffraction,Fourier transform infrared spectra. Scanning electron microscopy and transmission electron microscopy reveal that the grown β-Ga2O3 nanorods have a smooth and clean surface with diameters ranging from 100 nm to 200 nm and lengths typically up to 2μm. High resolution TEM and selected-area electron diffraction shows that the nanorods are pure monoclinic Ga2O3 single crystal. The photoluminescence spectrum indicates that the Ga2O3 nanorods have a good emission property. The growth mechanism is discussed briefly.

Preparation and Characterization of In_2O_3 Nanorods

In_2O_3 nanorods were prepared by sol-gel technique with nonionic surfactant controlling their morphology,and were characterized by TEM,TG-DSC and XRD.The results indicated that In_2O_3 nanorods had the length of about 120 nm and diameter of 20 nm.The In_2O(OH)_4 dried gelatin was formed by partial dehydrating of In(OH)_3 molecules.The factors influencing the morphology of In_2O_3 nanorods and their growth mechanism were discussed.The geometry array parameter P of the nonionic surfactant was between 1/3～1/2 through calculation,which confirmed that the shape of the micelle was claviform.

Simple Template-Free Synthesis of Bi₂O₃Microflowers Composed of Nanorods

This paper reports that α-Bi2O3 microflowers can be synthesized by an extremely simple and easy approach of inducing a reaction through the addition of NaOH aqueous solution to a mixed aqueous solution of Bi(NO3)3·5H2O and HNO3 scanning electron microscopy images of the Bi2O3 microflowers indicate that the Bi2O3 nanorods grew radially from the centre of the microflower to form the microflower shape. The findings of this study show that control of the reaction temperature, reaction time, and raw material mixture ratio plays an important role in the formation of α-Bi2O3 microflowers. It is especially revealed that α-Bi2O3 microflowers can be formed at low temperatures with short reaction times. It has thus far been reported that flower-shaped Bi2O3 particles or their precursors can be synthesized by the addition of additives such as organic molecules or certain inorganic ions. The present work reports on the discovery of ways to synthesize flower-shaped Bi2O3 particles without the use of special additives.

复合材料BN-B_2O_3纳米棒的制备

采用六角氮化硼(h-BN)粉末为原料,通过对h-BN粉末球磨得到BN纳米粉,并在管式炉中对BN纳米粉进行烧结,烧结环境分别为真空和空气.利用X射线衍射(XRD)和透射电子显微镜(TEM)研究所得样品的结构和成分.结果表明,样品为结晶较好的BN-B2O3纳米棒复合材料.

Synthesis of GaN Nanorods with Herringbone Morphology

Hexagonal GaN nanorods are synthesized on quartz substrates through ammoniating Ga 2O 3 thin films deposited by radio frequency magnetron sputtering.X ray diffraction (XRD),scanning electron microscopy (SEM),high resolution transmission electron microscopy (HRTEM),and photoluminescence (PL) are used to analyze the synthesized GaN nanorods.Among the products,one dimensional GaN nanostructures owning protuberances on the surface are detected,which show interesting herringbone morphology.The analysis reveals that the herringbone GaN nanorods are polycrystalline composed of overlapping parallelepiped GaN nanocrystals arranged along the major axis.The large blue shift of yellow PL luminescence of the nanorods is observed at room temperature.

Synthesis of GaN nanorods on Si substrates with assistance of the vola-tilization of ZnO middle layers

GaN nanorods have successfully been synthesized on Si(111) substrates via ammoniating ZnO/Ga2O3 films at 950 degrees C. Ga2O3 thin films and ZnO middle layers were deposited in turn on Si(111) substrates by r.f. magnetron sputtering system. ZnO volatilized at 950 degrees C in the ammonia ambience and Ga2O3 reacted to NH3 to fabricate GaN nanorods in the later ammoniating process. The volatilization of ZnO layers played an important role in the fabrication. The structure and composition of the GaN nanorods were studied by X-ray diffraction (XRD) and Fourier transform infrared spectrophotometer (FTIR). The morphology of GaN nanorods was investigated using scanning electron microscopy (SEM) and transmission electronic microscope (TEM). The analyses of measured results revealed that GaN nanorods with hexagonal wurtzite structure were prepared by this method.

In-situ scalable fast fabrication of Cu-Cu_(2+1)O nanorods for highly efficient electrocatalytic reduction into ammonia under neutral medium

The development of a highly efficient and durable electrocatalyst for nitrate reduction reaction(NO_(3)RR)wastewater valorization to ammonia(NH_(3))is a promising strategy.However,it is challenging to design scalable low-cost electrocatalysts with high activity,high selectivity,and long-term stability by a facile and simple method.Herein,we construct this scalable Cu-based nanoarray with muti-oxidation states grown directly on nickel foam(NF)substrate(Cu_(2+1)O@Cu/NF)using a facile molten salt method combined in-situ electrochemical reduction.The as-prepared Cu_(2+1)O@Cu/NF nanoarrays reveal a high NH_(3) yield of 20.14 mg h^(−1) cm^(−2) at−0.95 V vs.a reversible hydrogen electrode(vs.RHE),Faradaic efficiency of 99.38%at−0.55 V vs.RHE in the neutral potassium phosphate(PBS)buffer solution with 50 mM NaNO_(3),which is ascribed to its electron redistribution with abundant oxygen vacancies and favorable charge/mass transfer.

Effect of impregnation strategy on catalytic hydrogenation behavior of PtCo catalysts supported on La2O2CO3 nanorods

Small Pt and Pt-Co nanoparticles（NPs） stabilized on La2 O2 CO3 nanorods（LOC） were prepared by wet impregnation method,and probed in liquid-phase chemoselective hydrogenation of crotonaldehyde（CRAL） to crotyl alcohol（CROL）.It is found that incorporation of Co atoms into Pt catalyst significantly improves the hydrogenation activity and desired selectivity to CROL as it destroys the Pt-lanthanum interfaces and results into the formation of Pt-Co particles.In addition,a close examination of catalyst surface and reactive performance suggests that the impregnation sequence of Pt and Co exerts great influence on the physicochemical property and the catalytic hydrogenation behavior of PtCo/LOC catalysts.As a result of the interaction between Pt and Co species,high alloying degree of Pt-Co NPs is obtained in the co-impregnated catalyst（Pt-Co/LOC）,thus achieving the highest hydrogenation activity.The selective deposit of Co atoms onto the low-coordinated Pt sites leads to the smallest metal particle size and high dispersion of Pt-Co NPs over the Pt/Co/LOC,giving rise to the highest selectivity and yield to CROL.

Superstructured α-Fe2O3 nanorods as novel binder-free anodes for high-performing fiber-shaped Ni/Fe battery

Fiber-shaped energy storage devices are indispensable parts of wearable and portable electronics.Aqueous rechargeable Ni/Fe battery is a very appropriate energy storage device due to their good safety without organic electrolytes, high ionic conductivity, and low cost. Unfortunately, the low energy density,poor power density and cycling performance hinder its further practical applications. In this study, in order to obtain high performance negative iron-based material, we first synthesized a-iron oxide(α-Fe2O3) nanorods(NRs) with superstructures on the surface of highly conductive carbon nanotube fibers(CNTFs), then electrically conductive polypyrrole(PPy) was coated to enhance the electron, ion diffusion and cycle stability. The as-prepared α-Fe2O3@PPy NRs/CNTF electrode shows a high specific capacity of 0.62 Ah cm-3 at the current density of 1 A cm-3. Furthermore, the Ni/Fe battery that was assembled by the above negative electrode shows a maximum volumetric energy density of 15.47 mWh cm-3 with228.2 mW cm-3 at a current density of 1 A cm-3. The cycling durability and mechanical flexibility of the Ni/Fe battery were tested, which show good prospect for practical application. In summary, these merits make it possible for our Ni/Fe battery to have practical applications in next generation flexible energy storage devices.

Preparation of Nd_2O_3 nanorods in SDBS micelle system

Well-crystallized Nd2O3 nanorods were prepared in the aqueous solution containing neodymium nitrate, sodium hydroxide（dissolved in ethanol） and sodium dodecyl benzene sulfonate（SDBS）. One dimensional nanorods of neodymium hydroxide were synthesized first, which was then placed at different temperatures（600 and 800 ℃） in a calcar for 10 h to form Nd2O3 nanorods. The morphology and crystal structure of the products were investigated by X-ray diffraction, transmission electron microscopy, field emission transmission electron microscopy, Fourier transform infrared spectroscopy and fluorescence spectrometry. By using SDBS micelles as a template, this method manufactured uniform morphology of hexagonal one-dimensional neodymium oxide nanorods with a diameter ranging from 20 to 70 nm. The length of the nanorods increased with prolonged reaction time.

Hydrothermal route to Eu doped LuO(OH) and Lu_2O_3 nanorods

A facile method was developed to synthesize Eu doped LuO(OH) nanorods through hydrothermal processing and Lu2O3 nanorods by subsequent calcining.The microstructural morphologies of the Lu-based nanostructures could be controlled by simply varying the concentration of NaOH in hydrothermal processing as mineralizer.TEM observation revealed that the obtained LuO(OH) nanorods after hydrothermal processing had a uniform diameter of 10-25 nm and a length around 100 nm.After heat treatment at 600-700°C for 2 h,the high length/diameter ratio was sustained in the obtained Lu2O3 nanorods with different sizes depending on the calcining temperatures.

Fabrication of doxorubicin and chlorotoxin-linked Eu-Gd2O3 nanorods with dual-model imaging and targeted therapy of brain tumor

It is urgent to find a technology accurately to better diagnose and treat to brain tumor.Eu-doped Gd2 O3 nanorods(Eu-Gd2 O3 NRs)with paramagnetic and fluorescent properties were conjugated with doxorubicin(Dox)and chlorotoxin(CTX)via PEGylation,hydrazone bond and sulfur bond(named as CTXNRs-Dox),and these NRs could release more Dox in lower pH environment.The results of cell experiments indicated that CTX-NRs-Dox had obvious targeting and toxic effects on U251 cells,as well as good fluorescence imaging behavior.The orthotopic glioma-transplanted mice models were constructed via the intracranial injection of glioma cells(U87 MG).The result of experiments after the tail-vein injection of the prepared NRs suggested that CTX-NRs-Dox could target to brain tumors via the long-time blood circulation,leading to their obvious contrast enhancement of MR imaging of the intracranial tumor and their significant inhibitory effect on the growth and metastasis of brain tumors.A mechanism of synergistic effect of CTX-NRs-Dox on targeting and inhabiting the brain tumor was proposed.Our research suggested that CTX-NRs-Dox had potential application prospect in the detection and treatment of glioma.

Synthesis and in-situ noble metal modification of WO3·0.33H2O nanorods from a tungsten-containing mineral for enhancing NH3 sensing performance

Ag-and Pt-doped WO3-0.33 H2O nanorods with high response and selectivity to NH3 were synthesized from a tungsten-containing mine ral of scheelite concentrate by a simple combined process,namely by a high pressure leaching method to obtain tungstate ions-containing leaching solution and followed by a hydrothermal method to prepare corresponding nanorods.The microstructure and NH3 sensing perfo rmance of the final products were investigated systematically.The microstructure characte rization showed that the as-prepared WO3-0.33 H2 O nanorods had a hexagonal crystal structure,and Ag and Pt nanoparticles were uniformly distributed in the WO3-0.33 H2O nano rods.Gas sensing measurements indicated that Ag and Pt nanopa rticles not only could obviously enhance NH3 sensing properties in terms of response,selectivity as well as response/recovery time,but also could reduce the optimal operating temperature at which the highest response was achieved.The highest responses of 22.4 and 47.6 for Agand Pt-doped WO3-0.33 H2O nanorods to 1000 ppm NH3 were obtained at 225 and 175℃,respectively,which were about four and eight folds higher than that of pure one at 250℃.The superior NH3 sensing properties are mainly ascribed to the catalytic activities of noble metals and the different work functions between noble metals and WO3-0.33 H2 O.

Interface engineering of high efficiency perovskite solar cells based on ZnO nanorods using atomic layer deposition

Despite the considerably improved efficiency of inorganic-organic metal hybrid perovskite solar cells （PSCs）, electron transport is still a challenging issue. In this paper, we report the use of ZnO nanorods prepared by hydrothermal self- assembly as the electron transport layer in perovskite solar cells. The efficiency of the perovskite solar cells is significantly enhanced by passivating the interfacial defects via atomic layer deposition of Al2O3 monolayers on the ZnO nanorods. By employing the Al2O3 monolayers, the average power conversion efficiency of methylammonium lead iodide PSCs was increased from 10.33% to 15.06%, and the highest efficiency obtained was 16.08%. We suggest that the passivation of defects using the atomic layer deposition of monolayers might provide a new pathway for the improvement of all types of PSCs..

Shape dependence of support for NO_x storage and reduction catalysts

Pt/BaO/Al_2O_3 catalysts with different BaO loadings prepared from Al_2O_3 nanorods(Pt/BaO/Al_2O_3-nr) and irregular Al_2O_3 nanoparticles(Pt/BaO/Al_2O_3-np) were investigated for NOx storage and reduction(NSR). The Pt/BaO/Al_2O_3 materials derived from Al_2O_3 nanorods always exhibited much higher NOx storage capacity(NSC) over the whole temperature range of 100–400°C than the corresponding Pt/BaO/Al_2O_3-np samples containing the same BaO loading, giving the maximum NSC value of 966.9 μmol/gcatat 400°C, 1.4 times higher than that of Pt/BaO/Al_2O_3-np. Higher catalytic performance of nanorod-supported NSR samples was also observed during lean-rich cyclic conditions(90 sec vs. 5 sec), giving more than 98% NOx conversion at 300–450°C over the Pt/BaO/Al_2O_3-nr sample with 15% BaO loading. To reveal this dependence on the shape of the support during the NSR process, a series of characterization techniques including the Brunauer–Emmett–Teller(BET) method,X-ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS), H_2 temperature programmed reduction(H2-TPR), and in situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS) were also conducted. It was found that intimate contact of Ba–Al and Ba–Pt sites was achieved over the Pt/BaO/Al_2O_3 surface when using Al_2O_3-nr as a support.This strong interaction among the multi-components of Pt/BaO/Al_2O_3-nr thus triggered the formation of surface nitrite and nitrate during the lean period, and also accelerated the reverse spillover of ad-NOxspecies onto the Pt surface, enhancing their reduction and leading to high NSR performance.