hydrothermal

摘要： Nickel–cobalt tellurides are deemed as promising electrode materials for energy storage devices due to their superior conductivity and theoretical specific capacitance.Here,NiCoTe_(2)was successfully fabricated on carbon cloth by facile electrodeposition and hydrothermal synthesis,which can directly serve as a binderless electrode.The NiCoTe_(2)with interconnected nanosheet arrays on a conductive carbon substrate showed a high specific capacitance(924 F/g at 1 A/g)and robust longterm cycling stability(89.6%retention after 5000 cycles).In addition,the assembled NiCoTe_(2)//activiated carbon hybrid supercapacitor achieved a high energy and power density with a short charging time(42.26 Wh/kg at a power density of 760.96 W/kg).This work provides a novel idea to produce bimetallic nickel–cobalt telluride nanosheet array electrodes for high-performance hybrid supercapacitors.

摘要： In the present work,zinc oxide(ZnO)and silver(Ag)doped ZnO nanostructures are synthesized using a hydrothermal method.Structural quality of the products is attested using X-ray diffraction,which confirms the hexagonal wurtzite struc-ture of pure ZnO and Ag-doped ZnO nanostructures.XRD further confirms the crystallite orientation along the c-axis,(101)plane.The field emission scanning electron microscope study reveals the change in shape of the synthesized ZnO particles from hexagonal nanoparticles to needle-shaped nanostructures for 3 wt%Ag-doped ZnO.The optical band gaps and lattice strain of nanostructures is increased significantly with the increase of doping concentration of Ag in ZnO nanostructure.The anti-microbial activity of synthesized nanostructures has been evaluated against the gram-positive human pathogenic bacteria,Staphylococcus aureus via an agarose gel diffusion test.The maximum value of zone of inhibition(22 mm)is achieved for 3 wt%Ag-doped ZnO nanostructure and it clearly demonstrates the remarkable antibacterial activity.

摘要： Durian rind wastes are an important raw material for activated carbon production due to their renewable sources and low-cost materials.The efficiency of increasing surface area and the quantity of oxygen groups on the surface of activated carbon were studied for the preparation of activated carbon.The preparation of activated carbon has been studied with the different methods as follows:activation by acid,activation by base,hydrothermal and activation by acid,and hydrothermal and activation by base.The results showed that hydrothermal and activation by acid had high iodine number which was chosen to determine the optimum condition for activated carbon preparation.The optimum condition for preparation of durian rind activated carbon was studied by Box-Behnken design.Solid/water ratio,solid/acid ratio and temperature were chosen as the important parameters for achieving the optimum reaction condition.The reaction products were analyzed by iodine number.Based on the results,the optimum condition for preparation of durian rind activated carbon was predicted using RSM.The maximum iodine number of 626.47 mg/g was expected at the optimum condition:solid/water ratio(1:175,g/mL),solid/acid ratio(1:23,g/mL)and temperature(500°C).The preparation of durian rind activated carbon at the optimal condition was carried;the percentages of iodine number achieved(666.73±6 mg/g)were close to the maximum predicted value(666.73 mg/g),thus verifying the model.At the optimum condition,the functional group on surface of durian rind activated carbon was characterized by FT-IR.The result showed that the oxygen content on surface was increased in the form of carbonyl and sulfonyl group.

摘要： Nano or micro-scale particles are considered as a zero-dimensional material,and their shape is difficult to control.Here the crystal-like microparticles are formed,and the existence criterion of crystal-like low dimensional materials is established.The hydrothermal method is used to fabricate copper-1,3,5-phenyltricarboxylate(Cu-BTC)microparticles,which have a regular geometric shape with regular triangle,quadrangle and hexagon.The benzene ring and carboxyls(-COOH)attached to the benzene ring form two basic molecular structures of[Cu3(BTC)2]n,which play an essential role in the construction of a three-dimensional crystal-like structure.

摘要： The Halo copper-molybdenum prospect is a porphyry system in Ratanakiri province, northeastern part of Cambodia. There is only one research was carried out on this prospect about geological mapping and short wave infrared (SWIR) spectroscopy on alteration mineral identification. The purpose of this research is to confirm the deposit type from previous Angkor Gold’s report and find the centre of porphyry deposit based on characteristic of intrusive rocks at surface and subsurface, characteristics of the intrusive rocks and alteration lithogeochemistry of intrusive and volcanic rocks by using Pearce Element Ratio (PER) analysis. PER analysis was used to examine the nature and extend of the alteration halos in the porphyry Halo copper-molybdenum prospect. The intrusive rocks and volcanic rocks in Halo, range from diorite to granite (quartz feldspar porphyry) in composition as well as dacite to trachyandesite (andesite porphyry) in composition, respectively. They were formed in a subduction-related tectonic setting, likely a volcanic arc. Trace elements spider diagrams were normalized to primitive mantle display strong enrichment in large-ion lithophile elements such as Rb, Ba and K and depletion in some high-field strength elements such as Nb and Ti, suggesting magmas generated in a subduction-related tectonic setting. PER analysis indicates a moderate to high degree of sericite alteration of dacites, quartz feldspar porphyries, andesite porphyries and granodiorite porphyries. Moreover, three alterations in the Halo prospect such as potassic (secondary K-feldspar and biotite), phyllic (sericite) and propylitic (epidote) alteration were identified, which are consistent with petrography analysis. The potassic alteration zone is vectoring center of the hydrothermal system which may represent the locus of mineralization. Therefore the geochemical signature of potassic alteration within the quartz feldspar porphyry, andesite porphyry and granodioriteporphyry with high grad of copper ranges up to 2670 ppm and molybdenum ranges up to 5297 ppm represents a character for further exploration in the Halo porphyry copper-molybdenum prospect.

摘要： This study examines the behavior of trace- and rare-earth elements (REE) in different hydrothermal alteration facies (silicic, advanced argillic and argillic) of Cijulang high-sulfidation epithermal gold deposit, West Java, Indonesia. The results of the study indicate that remarkable differences in the behavior of trace elements and REE are observed in the studied alteration facies. All REE in the silicic facies are strongly depleted. In advanced argillic facies, Heavy rare-earth elements (HREE) are strongly depleted whereas light rare earth elements (LREE) are quite enriched. REE concentrations in the argillic facies show little or no variation with respect to fresh rock counterparts. A strong depletion of REE in the silicic facies is likely to be favored by the highly acidic nature of the hydrothermal fluids, the abundance of complexing ions such as Cl ˉ, F ˉ, and in the hydrothermal solutions and the absence of the secondary minerals that can fix the REE in their crystal structures. An apparent immobility of LREE in advanced argillic facies is possibly due to the presence of alunite. The immobility of REE in the argillic facies suggests the higher pH of the fluids, the lower water/rock ratios and the presence of the phyllosilicates minerals. -

摘要： In this article,we report ferroelectric properties of copper ferrite CuFe2O4 nanoparticles(CFN),Barium ferrite nanoparticles BaFe2O4(BFN)and La substituted barium ferrite Ba0.2La0.8Fe2O4(BLFN)nanoparticles synthesized via hydrothermal technique.The X-Ray diffraction for the synthesized particles reflects the cubic phase formation for CuFe2O4,orthorhombic phase structure for the BaFe2O4 and cubic formation of Ba0.2 La0.8Fe2O4(BLFN).The structural parameters such as crystallite size and micro-strain are computed from XRD and Williamson-Hall(W-H)analysis.The polarization-electric field(P-E)loop studies gave information about the ferroelectric nature of the synthesized samples.It was noticed that the CFN particle has a lossy dielectric nature whereas BFN,BLFN samples exhibit a multiferroic nature.

摘要： ZnO-MxOy heterostructures (M=Co, Mn, Ni, or In) are fabricated via hydrothermal synthesis method. X-ray diffraction and Fourier-transform infrared spectroscopy analyses endorse the successive formation of the various heterostructures. Field Emission Scanning electron microscope and Brunauer-Emmett-Teller (BET) surface area studies confirm the porous nature of the heterostructures obtained. The band gaps of various heterostructures are calculated that, 3.1, 2.71, 2.64, and 2.19 eV for ZnO-NiO, ZnO-In2O3, ZnO-Co3O4, and ZnO-MnO2, respectively. The photocatalytic activities of the fabricated heterostructures are investigated through the degradation of phenol under direct sunlight irradiation. The results show that the photocatalytic activity is affected by the conduction band (CB) and valence band (VB) positions rather than surface area of ZnO-MxOy heterostructure nanocomposites.