Hollow engineering plays a crucial role in enhancing interfacial polarization,which is an essential factor in microwave absorption.Herein,an in-situ growth approach was adopted to successively coating C layer and WS_(...Hollow engineering plays a crucial role in enhancing interfacial polarization,which is an essential factor in microwave absorption.Herein,an in-situ growth approach was adopted to successively coating C layer and WS_(2) nanosheets on the surface SiO_(2) nanosphere.The obtained results suggested that the formed SiO_(2)@Void@C@WS_(2) multi-component nanocomposites(MCNCs)reveal a representative flower-like yolk-shell structure,which were manufactured massively through a simple channel.Additionally,the obtained SiO_(2)@Void@C@WS_(2) MCNCs presented a more and more obvious yolk-shell structure and reduced WS_(2) content with decreasing the addition of SiO_(2)@C or tungsten and sulfur sources.Because of their distinc-tive structures and remarkable cooperative effects,the SiO_(2)@Void@C@WS_(2) displayed excellent microwave absorption performances.Through the majorization of hollow structure and WS_(2),improved properties of SiO_(2)@Void@C@WS_(2) MCNCs could be acquired owing to their boosted polarization and conductive loss capabilities.Amongst,the resulting SiO_(2)@Void@C@WS_(2) MCNCs exhibited the effective absorption band and minimum reflection loss values of 5.40 GHz and−45.50 dB with matching thicknesses of 1.78 and 1.55 mm,respectively.Therefore,our findings employed hollow engineering and optimization strategies for components to design and fabricate the yolk-shell structure flower-like MCNCs,which acted as highly efficient wide-band microwave absorbing materials.展开更多
The present levels of CO_(2)emission in the atmosphere require the development of technologies to achieve carbon neutrality using inexpensive processes.Conversion of CO_(2)into cyclic carbonates is one of the solution...The present levels of CO_(2)emission in the atmosphere require the development of technologies to achieve carbon neutrality using inexpensive processes.Conversion of CO_(2)into cyclic carbonates is one of the solutions to this problem.Here,we synthesized a ZnV_(2)O_(6)/Bi_(2)WO_(6)nanocomposite and catalyzed the cycloaddition of CO_(2)to epoxides for the green synthesis of cyclic carbonates under visible light irradiation.The present nanocomposite photocatalyst exhibited up to 96%yield of cyclic carbonates.The photocatalyst was found to be efficient for photocatalytic cycloaddition reactions,and the recovered photocatalyst showed stability in up to five consecutive photocatalytic experiments.The current methodology of cyclic carbonate production is a significant step toward the mitigation of atmospheric CO_(2)and can work well with the development of nanocomposite photocatalysts.展开更多
The effective detection of trace methyl mercaptan(CH_(3)SH)with low power consumption is crucial for assessing air quality and facilitating non-invasive diagnosis of diseases such as periodontitis.Herein,we synthesize...The effective detection of trace methyl mercaptan(CH_(3)SH)with low power consumption is crucial for assessing air quality and facilitating non-invasive diagnosis of diseases such as periodontitis.Herein,we synthesized a ternary CeO_(2)-ZnO-Ag nanocomposite by a simple sol-gel one-step method,which shows the capability of monitoring ppb-level CH_(3)SH under room temperature.The incorporation of Ag significantly reduces the particle size and increases the ratio of Ce^(3+)as well as oxygen vacancy.Furthermore,Ag nanoparticles improve light utilization efficiency in CeO_(2)-ZnO composites in favor of the separation of photo-generated charge carriers.The sensor based on the nanocomposites with 2 mol%Ag exhibits an exceptional response of 1.21 towards 50 ppb CH3SH at room temperature under photoassisted excitation(395 nm).Moreover,it shows a stable detection even in an environment with 57.6% humidity and high selectivity towards CH_(3)SH gas.The gas sensing mechanism study indicates that the enhancement in perfo rmance is prima rily attributed to an increased number of oxygen vacancies and the spillover effect of Ag,ultimately leading to an augmented reaction rate of CH_(3)SH on the surface of the sensing material.This work demonstrates that the optimized CeO_(2)-ZnO-Ag nanocomposites hold great promise for highly selective and sensitive detection of trace CH_(3)SH gas under specific humidity conditions.展开更多
To overcome the limited electronic conductivity and capacity of single and binary transition metal phos-phates(TMPs),highly electrochemical active materials and rational structural design of ternary TMPs composite are...To overcome the limited electronic conductivity and capacity of single and binary transition metal phos-phates(TMPs),highly electrochemical active materials and rational structural design of ternary TMPs composite are urgently required.In this study,we successfully synthesized an amorphous 3D Ni-Co-Mn phosphate@2D Ti_(3)C_(2)T_(x)(MXene)nanocomposite(NCMP series)through the electrodeposition method.The amorphous Ni-Co-Mn phosphate effectively restricts the self-accumulation of MXene nanosheets,result-ing in the development of a porous nanostructure.This structure exposes more active sites,expands the ion transport path,and enhances the conductivity of the Ni-Co-Mn phosphate@Ti_(3)C_(2)T_(x) material.Owing to the synergistic effect offered by Ni-Co-Mn phosphate and MXene nanocomposite,the anchored Ni-Co-Mn phosphate@Ti_(3)C_(2)T_(x)(NCMP-5)electrode delivers an elevated capacity of 342 mAh/g(1230 C/g)at 5.0 A/g,surpassing the pristine Ni-Co-Mn phosphate(NCMP-4,260 mAh/g)and MXene(33.3 mAh/g).Moreover,a hybrid solid-state supercapacitor(HSSC)device is assembled with NCMP-5 as a cathode and reduced graphene oxide(rGO)as an anode within a polymer gel(PVA-KOH)electrolyte.Notably,the fabricated HSSC device displays a supreme specific capacity of 27.5 mAh/g(99 C/g)and a high(volumetric)energy density of 22 Wh/kg(3.6 Wh/cm^(3))at a power density of 0.80 kW/kg(0.13 kW/cm^(3))for 1.0 A/g.Moreover,the HSSC device retains 95.4%of its initial capacity even after 10,000 cycles.Importantly,the operational potential window of two serially connected HSSC devices approaches+3.2 V,enabling different colored commercial light-emitting diodes(LEDs)to be efficiently illuminated.Eventually,the remarkable super-capacitive characteristics of the 3D@2D amorphous Ni-Co-Mn phosphate@MXene nanocomposite make it an attractive choice for advanced electroactive materials in upcoming hybrid energy storage technologies.展开更多
Nanostructured MnO2/CNT composite was synthesized by a soft template approach in the presence of Pluronic P123 surfactant. The product was characterized by X-ray diffraction, thermogravimetric and differential thermal...Nanostructured MnO2/CNT composite was synthesized by a soft template approach in the presence of Pluronic P123 surfactant. The product was characterized by X-ray diffraction, thermogravimetric and differential thermal analyses, Fourier transformed infrared spectroscopy and high-resolution transmission electron microscopy. The results show that the sample consists of poor crystalline α-MnO2 nanorods with a diameter of about 10 nm and a length of 30-50 nm, which absorb on the carbon nanotubes. The electrochemical properties of the product as cathode material for Li-MnO2 cell are evaluated by galvanostatic charge-discharge and electrochemical impedance spectroscopy （EIS）. Compared with pure MnO2 electrode, the MnO2/CNT composite delivers a much larger initial capacity of 275.3 mA-h/g and better rate and cycling performance.展开更多
The preparation of TiO2/poly（L-lactide-co-ε-caprolactone）（PLCL） nanocomposites and their properties were reported.TiO2nanoparticles were surface modified by ring-opening polymerization of ε-caprolactone（ε-CL）...The preparation of TiO2/poly（L-lactide-co-ε-caprolactone）（PLCL） nanocomposites and their properties were reported.TiO2nanoparticles were surface modified by ring-opening polymerization of ε-caprolactone（ε-CL）.The resulting poly（ε-caprolactone）-grafted TiO2（g-TiO2） was characterized by Fourier transform infrared spectroscopy（FTIR）,thermogravimetric analysis（TGA） and transmission electron microscopy（TEM）.The g-TiO2can be uniformly dispersed in chloroform and the g-TiO2/PLCL nanocomposites were successfully fabricated through solvent-casting method.The effects of the content of g-TiO2nanoparticles on tensile properties and shape memory properties were investigated.A significant improvement in the tensile properties of the 5% g-TiO2/PLCL mass fraction nanocomposite is obtained：an increase of 113% in the tensile strength and an increase of 11% in the elongation at break over pure PLCL polymer.The g-TiO2/PLCL nanocomposites with a certain amount of g-TiO2content have better shape memory properties than pure PLCL polymer.The g-TiO2nanoparticles play an additional physical crosslinks which are contributed to improvement of the shape memory properties.展开更多
Ni-Y2O3 nanocomposite powder with uniform distribution of fine oxide particles in the metal matrix was successfully fabricated via solution combustion process followed by hydrogen reduction. The combustion behavior wa...Ni-Y2O3 nanocomposite powder with uniform distribution of fine oxide particles in the metal matrix was successfully fabricated via solution combustion process followed by hydrogen reduction. The combustion behavior was investigated by DTA-TG analysis. The influence of urea to nickel nitrate（U/Ni） ratio on the combustion behavior and morphology evolution of the combusted powder was investigated. The morphological characteristics and phase transformation of the combusted powder and the reduced powder were characterized by FESEM, TEM and XRD. The HRTEM image of Ni-Y2O3 nanocomposite powder indicated that Y2O3 particles with average particle size of about 10 nm dispersed uniformly in the nickel matrix.展开更多
An innovative photocatalyst, Carbon nanotube （CNT） supported Ce-TiO2 nanocomposite was successfully synthesized via modi-fied sol gel method and investigated in a batch reactor for abolition of phenol under UV light...An innovative photocatalyst, Carbon nanotube （CNT） supported Ce-TiO2 nanocomposite was successfully synthesized via modi-fied sol gel method and investigated in a batch reactor for abolition of phenol under UV light spectrum. Characterization of catalyst micro-structure and internal properties were done by means of X-ray diffraction （XRD）, Brunauer-Emmett-Teller （BET）, scanning electron micros-copy （SEM）, transmission electron microscopy （TEM） and UV-vis diffuse reflectance spectra （DRS）. Ce doping can inhibit phase transfor-mation from anatase to rutile and eliminate the recombination of electron-hole pairs in the catalyst. The presence of CNT in TiO2 composite can both increase the photoactivity under UV and change surface properties to achieve sensitivity to visible light. The optimum mass ratio of CNT support and cerium （Ce） dopant in TiO2 was the prominent factor to harvest CNT/Ce-TiO2 photocatalyst nanocomposite. The results demonstrated that optimum mass ratio of CNT：TiO2：Ce was 0.02：1.0：0.06, which resulted in the great performance of the photocatalyst to de-grade about 94% of phenol in a 50 mg/L solution in only 3 h. In this paper, dissimilar role of CNT support and Ce dopant in the TiO2 photo-catalysis of phenol was also discussed.展开更多
A BiOCl-Bi12O17Cl2 nanocomposite with a high visible-light response and a low photoinduced electron-hole pair recombination rate was successfully synthesized using an ultrasonic-hydrothermal method.The texture,structu...A BiOCl-Bi12O17Cl2 nanocomposite with a high visible-light response and a low photoinduced electron-hole pair recombination rate was successfully synthesized using an ultrasonic-hydrothermal method.The texture,structure,optical,and photocatalytic properties of the composite were characterized.The results showed that the composite had a sheet flower-like structure with a large specific surface area.Ultraviolet-visible diffuse reflection spectra and photoluminescence spectra showed that the composite had an excellent visible-light response and a low recombination rate of photoinduced electron hole pairs.The photocatalytic property of the composite was evaluated by the removal efficiency of rhodamine B and ciprofloxacin under visible-light illumination.The composite’s reaction rate constant of removing rhodamine B(/ciprofloxacin)was approximately 8.14(/4.94),42.63(/11.91)and 64.66(/36.07)times that of Bi12O17Cl2,P25,and BiOCl,respectively.Furthermore,the composite showed a wide applicable pH range and excellent reusability.Mechanism analysis showed that photogenerated holes played a dominant role and·O2–also contributed to photocatalytic degradation.In summary,this study presents a high-efficiency photocatalyst for wastewater treatment.展开更多
Surface-functionalized nitrogen/carbon co-doped polymorphic TiO_(2) phase junction nanoparticles uniformly distributed in porous carbon matrix were synthesized by a simple one-step pyrolysis of titanium based metal-or...Surface-functionalized nitrogen/carbon co-doped polymorphic TiO_(2) phase junction nanoparticles uniformly distributed in porous carbon matrix were synthesized by a simple one-step pyrolysis of titanium based metal-organic framework(MOF),NH_(2)-MIL^(-1)25(Ti) at 700℃ under water vapour atmosphere.Introducing water vapour during the pyrolysis of NH_(2)-MIL^(-1)25(Ti) not only functionalizes the derived porous carbon matrix with carboxyl groups but also forms additional oxygen-rich N like interstitial/intraband states lying above the valence band of TiO2 along with the self-doped carbo n,which further narrows the energy band gaps of polymorphic TiO2 nanoparticles that enhance photocatalytic charge transfer efficiency.Without co-catalyst,sample N-C-TiO2/CArW demonstrates H_(2) evolution activity of 426 μmol gcat-1h^(-1),which remarkably outperforms commercial TiO_(2)(P-25) and N-C-TiO_(2)/CAr with a 5-fold and 3-fold H_(2) generation,respectively.This study clearly shows that water vapour atmosphere during the pyrolysis increases the hydrophilicity of the Ti-MOF derived composites by functionalizing porous carbon matrix with carboxylic groups,as well as enhancing the electrical conductivity and charge transfer efficiency due to the formation of additional localized oxygen-rich N like interstitial/intraband states.This work also demonstrates that by optimizing the anatase-rutile phase composition of the TiO2 polymorphs,tuning the energy band gaps by N/C co-doping and functionalizing the porous carbon matrix in the N-C-TiO2/C nanocomposites,the photocatalytic H_(2) generation activity can be further enhanced.展开更多
A simple electrodeposition technique was used to prepare Ni-CeOnanorods composite coating(Ni-CeONRs) using Watt’s nickel plating bath containing CeOnanorods(NRs) as the reinforcement phase under optimized process con...A simple electrodeposition technique was used to prepare Ni-CeOnanorods composite coating(Ni-CeONRs) using Watt’s nickel plating bath containing CeOnanorods(NRs) as the reinforcement phase under optimized process conditions. The X-ray diffraction analysis(XRD) was used for the structural analysis of Ni-CeONRs composite coatings and their average crystalline size is ～22 nm for pure Ni and ～18 nm,respectively. The crystalline structure is fcc for the Ni-CeOnanocomposite coatings. The surface morphology of the electrodeposited Ni-CeONRs composite coatings was analyzed by scanning electron microscopy(SEM). Microhardness of pure Ni and Ni-CeONRs composite coatings are found to be 253 HV and 824 HV, respectively. The inclusion of CeONRs increases the microhardness of Ni-CeONRs composite coatings. The corrosion resistance behavior of Ni-CeONRs composite coating was evaluated by Tafel polarization and AC impedance methods. It is revealed that CeONRs reinforced Ni matrix shows higher microhardness and corrosion resistance than existing reported electrodeposited pure Ni and CeOnanoparticles reinforced Ni coatings.展开更多
Surface of TiO2 nanoparticles was modified with the in situ chemical oxidative polymerization of aniline. Polyaniline modified TiO2 nanoparticles （PANI-TiO2） were characterized with the FT-IR, XRD, SEM and TEM techn...Surface of TiO2 nanoparticles was modified with the in situ chemical oxidative polymerization of aniline. Polyaniline modified TiO2 nanoparticles （PANI-TiO2） were characterized with the FT-IR, XRD, SEM and TEM techniques. Results confirmed that PANI was grafted successfully on the surface of TiO2 nanoparticles, therefore agglomeration of nanoparticles decreased dramatically. Polyvinyl chloride nanocomposites filled with 1 wt%-5 wt% of PANI-TiO2 and TiO2 nanoparticles were prepared via the solution blending method. PVC nanocomposites were analyzed with FT-IR, XRD, SEM, TG/DTA, DSC and tensile test techniques. Effect of PANI as surface modifier of nanoparticles was discussed according to the final properties of PVC nanocomposites. Results demonstrated that deposition of PANI on the surface of TiO2 nanoparticles improved the interfacial adhesion between the constituents of nanocomposites, which resulted in better dispersion of nanoparticles in the PVC matrix. Also PVC/PANI-TiO2 nanocomposites showed higher thennal resistance, tensile strength and Young＇s modulus compared to those of unfilled PVC and PVC/TiO2 nanocomposites.展开更多
Ag/TiO2/freeze-dried graphene nanocomposites have been prepared via a facile one-step solvothermal method for the photocatalytic degradation of Rh B under visible light irradiation. During the solvothermal process, re...Ag/TiO2/freeze-dried graphene nanocomposites have been prepared via a facile one-step solvothermal method for the photocatalytic degradation of Rh B under visible light irradiation. During the solvothermal process, reduction of graphene oxide and loading of Ag/TiO2nanoparticles on graphene sheets were achieved. Investigation of chemical state of products showed that covering of Ag/TiO2surface with higher weight ratio of graphene resulting in that Ag metals in Ag/TiO2were oxidized to Ag2 O in nanocomposite structure after solvothermal process. Degree of photocatalytic activity enhancement strongly depends on the coverage of Ag/TiO2surface by porous graphene. The sample of 1 wt% porous graphene hybridized Ag/TiO2showed the highest photocatalytic activity, which is related to high migration efficiency of photoinduced of electrons and reduction of electron–hole recombination rate due to high electrical conductivity of graphene. Expanding of absorption to visible light region was ascribed to surface plasmon resonance effect of Ag metals and presence of graphene. Investigation of photocatalytic performance of formic acid as a dye-less organic pollutant showed that dye sensitization effect of Rh B molecules during evaluation of photocatalytic performance was negligible.展开更多
A series of La2O3/MC nylon nanocomposites were prepared via in situ polymerization. The effects of content of nano-La2O3 on the mechanical properties of nanocomposites were studied. Dispersion of nano-La2O3 in MC nylo...A series of La2O3/MC nylon nanocomposites were prepared via in situ polymerization. The effects of content of nano-La2O3 on the mechanical properties of nanocomposites were studied. Dispersion of nano-La2O3 in MC nylon matrix was observed with SEM. The crystal structure of nanocomposites was characterized by means of XRD. SEM analysis shows that La2O3 nanoparticles are uniformly dispersed in MC nylon matrix and little clustering exists when the content of nano- La2O3 is lower than 1%, however, when the content of nano-La2O3 is more than 1%, it begins to cluster. XRD analysis indicats that nano-La2O3 does not change the crystal structure of MC nylon. Mechanical properties tests show that the tensile strength, elongation at break, impact strength, flexural strength, and flexural modulus of nanocomposites first increase then decrease as the content of nano-La2O3 is increased. When the content of nano-La2O3 is 0.5%, the tensile strength and elongation at break of nanocomposites reach maximum, which are 17.9% and 52.1% higher respectively than those of MC nylon. When the content of nano-La2O3 is 1.0%, the impact strength, flexural strength and flexural modulus of nanocomposites reach maximum, which are 36.6 %, 12.7 % and 16.3 % higher respectively than those of MC nylon.展开更多
In this investigation, polymeric nanocomposite membranes（PNMs） were prepared via incorporating zinc oxide（ZnO） into poly（ether-block-amide）(PEBAX-1074) polymer matrix with different loadings. The neat membrane a...In this investigation, polymeric nanocomposite membranes（PNMs） were prepared via incorporating zinc oxide（ZnO） into poly（ether-block-amide）(PEBAX-1074) polymer matrix with different loadings. The neat membrane and nanocomposite membranes were prepared via solution casting and solution blending methods, respectively. The fabricated membranes were characterized by field emission scanning electron microscopy（FESEM） to survey cross-sectional morphologies and thermal gravimetric analysis（TGA）to study thermal stability. Fourier transform infrared（FT-IR） and X-ray diffraction（XRD） analyses were also employed to identify variations of the chemical bonds and crystal structure of the membranes, respectively. Permeation of pure gases, CO, CHand Nthrough the prepared neat and nanocomposite membranes was studied at pressures of 3–18 bar and temperature of 25 °C. The obtained results showed that the fabricated nanocomposite membranes exhibit better separation performance compared to the neat PEBAX membrane in terms of both permeability and selectivity. As an example, at temperature of 25 °C and pressure of 3 bar, COpermeability, ideal CO/CHand CO/Nselectivity values for the neat PEBAX membrane are 110.67 Barrer, 11.09 and 50.08, respectively, while those values are 152.27 Barrer,13.52 and 62.15 for PEBAX/ZnO nanocomposite membrane containing 8 wt% ZnO.展开更多
Multi-functionalized and co-doped TiO_(2)/C nanocomposites were derived from the pyrolysis of Ti-MOFs at 800℃under different gaseous atmospheres and their photocatalytic performance were investigated.The gaseous atmo...Multi-functionalized and co-doped TiO_(2)/C nanocomposites were derived from the pyrolysis of Ti-MOFs at 800℃under different gaseous atmospheres and their photocatalytic performance were investigated.The gaseous atmosphere during pyrolysis plays a critical role in determining the structural,textural,optical and physicochemical properties of the derived TiO_(2)/C composites due to the synergistic effect of nitrogen-containing species,carboxylate and sulfur functionalized porous carbon as well as N/S co-doped TiO_(2)nanoparticles.All the Ti-MOFs derived TiO_(2)/C composites exclusively possess homogeneously distributed TiO_(2)nanoparticles in a functionalized disc-like porous carbon matrix and demonstrate much enhanced adsorption and photodegradation performance than commercial TiO_(2)under the same conditions.The adsorption of methylene blue(MB)in dark on these TiO_(2)/C composites are dominated with pseudo second-order kinetic model and the high adsorption capacity of MB in dark on composite TiO_(2)/C derived from MIL-125(Ti)in argon is due to its high surface area with predominant mesoporous carbon matrix in the composite.The composite N-O-TiO_(2)/C derived from NH2-MIL-125(Ti)in water vapor exhibited the highest photodegradation activity with 99.7%MB removal in 3 h under visible light due to the optimal anatase/rutile phasejunction,together with the formation of photoactive oxygen-rich N-O like interstitial/intraband states above the valence band of TiO_(2),as well as the presence of N-containing species and-OH/-COOH multi-functional groups with superhydrophilic nature of the composite.This simple one-step and easily modifiable approach can be further employed to modulate homogeneously dispersed multi-functionalized and co-doped metal oxide/carbon nanocomposites for various environment and energy-related applications.展开更多
Two-dimensional(2D)nanomaterials have demonstrated great potential in the field of flexible gas sensing due to their inherent high specific surface areas,unique electronic properties and flexibility property.However,n...Two-dimensional(2D)nanomaterials have demonstrated great potential in the field of flexible gas sensing due to their inherent high specific surface areas,unique electronic properties and flexibility property.However,numerous challenges including sensitivity,selectivity,response time,recovery time,and stability have to be addressed before their practical application in gas detection field.Development of graphene-like 2D/2D nanocomposites as an efficient strategy to achieve high-performance 2D gas sensor has been reported recently.This review aims to discuss the latest advancements in the 2D/2D nanocomposites for gas sensors.We first elaborate the gas-sensing mechanisms and the collective benefits of 2D/2D hybridization as sensor materials.Then,we systematically present the current gas-sensing applications based on different categories of 2D/2D nanocomposites.Finally,we conclude the future prospect of 2D/2D nanocomposites in gas sensing applications.展开更多
An efficient visible-light-responsive BiOBr/TiO2 heterojunction nanocomposite was fabricated successfully using in-situ depositing technique at room temperature by introducing BiOBr onto the surface of TiO2 nano- belt...An efficient visible-light-responsive BiOBr/TiO2 heterojunction nanocomposite was fabricated successfully using in-situ depositing technique at room temperature by introducing BiOBr onto the surface of TiO2 nano- belts pre-prepared by hydrothermal reaction and etched with H2SO4. The obtained particles were characterized by XRD, SEM, TEM, XPS, UV-Vis DRS and PL techniques. BiOBr/TiO2 heterojunction nanocomposites with different mass ratios of m （BiOBr）/m （TiO2） were discussed in order to get the best photocatalytie activity, and BiOBr/TiO2-1.0 was proved to be the optimal mass ratio. BiOBr/TiO2-1.0 exhibited excellent photocatalytic activity in the degradation of RhB compared with TiO2 nanobelts, pure BiOBr and the mechanical mixture of TiO2 nanobelts and BiOBr. At last, a possible mechanism ofphotocatalytic enhancement was proposed.展开更多
In this study, for marine application purposes, we evaluated the effect of process parameter and particle loading on the microstructure, mechanical reinforcement and corrosion resistance properties of a Zn-TiO2-WO3 na...In this study, for marine application purposes, we evaluated the effect of process parameter and particle loading on the microstructure, mechanical reinforcement and corrosion resistance properties of a Zn-TiO2-WO3 nanocomposite produced via electrodeposition. We characterized the morphological properties of the composite coatings with a Scanning Electron Microscope （SEM） equipped with an Energy Dispersive Spectrometer （EDS）. We carried out mechanical examination using a Dura Scan hardness tester and a CERT UMT-2 multi-functional tribological tester. We evaluated the corrosion properties by linear polarization in 3.5% NaCl. The results show that the coatings exhibited good stability and the quantitative particle loading greatly enhanced the structural and morphological properties, hardness behavior and corrosion resistance of the coatings. We observed the precipitation of this alloy on steel is greatly influenced by the composite characteristics.展开更多
In this work, a series of Cu2O-Ag/ZnO, Cu2O/ZnO and Ag/ZnO nanocomposites with various compositions were prepared via a hydrothermal method followed by chemical modification, and their antibacterial performance was in...In this work, a series of Cu2O-Ag/ZnO, Cu2O/ZnO and Ag/ZnO nanocomposites with various compositions were prepared via a hydrothermal method followed by chemical modification, and their antibacterial performance was investigated in detail. X-ray powder diffraction, scanning electron microscopy and transmission electron microscopy results confirmed that 31 nm Cu20 and 30 nm Ag nanoparticles are well-dispersed on 202 nm ZnO grains to form a Cu2O/ZnO and Ag/ZnO heterojunction, respectively. The bi-heterojuction structure in the Cu20-Ag/ZnO provided a synergistic effect on antibacterial activity, and the(Cu2O)0.04Ag0.06ZnO0.9nanocomposites showed the highest antimicrobial activity of all samples with minimum inhibitory concentration and minimum bactericidal concentration against Escherichia coli and Staphylococcus aureus as low to 31.25 μg/mL, 250μg/mL, 125μg/mL and 500μg/mL, respectively. This is the first report of the antibacterial activities of Cu2O and Ag co-modified ZnO nanocomposites.展开更多
基金supported by the Guizhou Provincial Science and Technology Projects for Platform and Talent Team Plan(No.GCC[2023]007)the Innovation Group of Guizhou University([2024]08)+1 种基金Fok Ying Tung Education Foundation(No.171095)the National Natural Science Foundation of China(No.11964006).
文摘Hollow engineering plays a crucial role in enhancing interfacial polarization,which is an essential factor in microwave absorption.Herein,an in-situ growth approach was adopted to successively coating C layer and WS_(2) nanosheets on the surface SiO_(2) nanosphere.The obtained results suggested that the formed SiO_(2)@Void@C@WS_(2) multi-component nanocomposites(MCNCs)reveal a representative flower-like yolk-shell structure,which were manufactured massively through a simple channel.Additionally,the obtained SiO_(2)@Void@C@WS_(2) MCNCs presented a more and more obvious yolk-shell structure and reduced WS_(2) content with decreasing the addition of SiO_(2)@C or tungsten and sulfur sources.Because of their distinc-tive structures and remarkable cooperative effects,the SiO_(2)@Void@C@WS_(2) displayed excellent microwave absorption performances.Through the majorization of hollow structure and WS_(2),improved properties of SiO_(2)@Void@C@WS_(2) MCNCs could be acquired owing to their boosted polarization and conductive loss capabilities.Amongst,the resulting SiO_(2)@Void@C@WS_(2) MCNCs exhibited the effective absorption band and minimum reflection loss values of 5.40 GHz and−45.50 dB with matching thicknesses of 1.78 and 1.55 mm,respectively.Therefore,our findings employed hollow engineering and optimization strategies for components to design and fabricate the yolk-shell structure flower-like MCNCs,which acted as highly efficient wide-band microwave absorbing materials.
基金sponsored in part by the National Natural Science Foundation of China(No.21477167)the Science and Technology Research Plan Program of Henan Province(Nos.222102320328,232102210075,232102320137)the Key Science Research Program Foundation of High Education Schools of Henan Province(No.23B610010).
文摘The present levels of CO_(2)emission in the atmosphere require the development of technologies to achieve carbon neutrality using inexpensive processes.Conversion of CO_(2)into cyclic carbonates is one of the solutions to this problem.Here,we synthesized a ZnV_(2)O_(6)/Bi_(2)WO_(6)nanocomposite and catalyzed the cycloaddition of CO_(2)to epoxides for the green synthesis of cyclic carbonates under visible light irradiation.The present nanocomposite photocatalyst exhibited up to 96%yield of cyclic carbonates.The photocatalyst was found to be efficient for photocatalytic cycloaddition reactions,and the recovered photocatalyst showed stability in up to five consecutive photocatalytic experiments.The current methodology of cyclic carbonate production is a significant step toward the mitigation of atmospheric CO_(2)and can work well with the development of nanocomposite photocatalysts.
基金Project supported by China Postdoctoral Science Foundation(2020M673172)National Natural Science Foundation of China(61901401)。
文摘The effective detection of trace methyl mercaptan(CH_(3)SH)with low power consumption is crucial for assessing air quality and facilitating non-invasive diagnosis of diseases such as periodontitis.Herein,we synthesized a ternary CeO_(2)-ZnO-Ag nanocomposite by a simple sol-gel one-step method,which shows the capability of monitoring ppb-level CH_(3)SH under room temperature.The incorporation of Ag significantly reduces the particle size and increases the ratio of Ce^(3+)as well as oxygen vacancy.Furthermore,Ag nanoparticles improve light utilization efficiency in CeO_(2)-ZnO composites in favor of the separation of photo-generated charge carriers.The sensor based on the nanocomposites with 2 mol%Ag exhibits an exceptional response of 1.21 towards 50 ppb CH3SH at room temperature under photoassisted excitation(395 nm).Moreover,it shows a stable detection even in an environment with 57.6% humidity and high selectivity towards CH_(3)SH gas.The gas sensing mechanism study indicates that the enhancement in perfo rmance is prima rily attributed to an increased number of oxygen vacancies and the spillover effect of Ag,ultimately leading to an augmented reaction rate of CH_(3)SH on the surface of the sensing material.This work demonstrates that the optimized CeO_(2)-ZnO-Ag nanocomposites hold great promise for highly selective and sensitive detection of trace CH_(3)SH gas under specific humidity conditions.
基金supported by the National Research Foundation of Korea(NRF)(NRF-2021R1A2C1005867)supported by the Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(2021R1A6A1A03038996).
文摘To overcome the limited electronic conductivity and capacity of single and binary transition metal phos-phates(TMPs),highly electrochemical active materials and rational structural design of ternary TMPs composite are urgently required.In this study,we successfully synthesized an amorphous 3D Ni-Co-Mn phosphate@2D Ti_(3)C_(2)T_(x)(MXene)nanocomposite(NCMP series)through the electrodeposition method.The amorphous Ni-Co-Mn phosphate effectively restricts the self-accumulation of MXene nanosheets,result-ing in the development of a porous nanostructure.This structure exposes more active sites,expands the ion transport path,and enhances the conductivity of the Ni-Co-Mn phosphate@Ti_(3)C_(2)T_(x) material.Owing to the synergistic effect offered by Ni-Co-Mn phosphate and MXene nanocomposite,the anchored Ni-Co-Mn phosphate@Ti_(3)C_(2)T_(x)(NCMP-5)electrode delivers an elevated capacity of 342 mAh/g(1230 C/g)at 5.0 A/g,surpassing the pristine Ni-Co-Mn phosphate(NCMP-4,260 mAh/g)and MXene(33.3 mAh/g).Moreover,a hybrid solid-state supercapacitor(HSSC)device is assembled with NCMP-5 as a cathode and reduced graphene oxide(rGO)as an anode within a polymer gel(PVA-KOH)electrolyte.Notably,the fabricated HSSC device displays a supreme specific capacity of 27.5 mAh/g(99 C/g)and a high(volumetric)energy density of 22 Wh/kg(3.6 Wh/cm^(3))at a power density of 0.80 kW/kg(0.13 kW/cm^(3))for 1.0 A/g.Moreover,the HSSC device retains 95.4%of its initial capacity even after 10,000 cycles.Importantly,the operational potential window of two serially connected HSSC devices approaches+3.2 V,enabling different colored commercial light-emitting diodes(LEDs)to be efficiently illuminated.Eventually,the remarkable super-capacitive characteristics of the 3D@2D amorphous Ni-Co-Mn phosphate@MXene nanocomposite make it an attractive choice for advanced electroactive materials in upcoming hybrid energy storage technologies.
基金Projects(21071153,20976198)supported by the National Natural Science Foundation of China
文摘Nanostructured MnO2/CNT composite was synthesized by a soft template approach in the presence of Pluronic P123 surfactant. The product was characterized by X-ray diffraction, thermogravimetric and differential thermal analyses, Fourier transformed infrared spectroscopy and high-resolution transmission electron microscopy. The results show that the sample consists of poor crystalline α-MnO2 nanorods with a diameter of about 10 nm and a length of 30-50 nm, which absorb on the carbon nanotubes. The electrochemical properties of the product as cathode material for Li-MnO2 cell are evaluated by galvanostatic charge-discharge and electrochemical impedance spectroscopy （EIS）. Compared with pure MnO2 electrode, the MnO2/CNT composite delivers a much larger initial capacity of 275.3 mA-h/g and better rate and cycling performance.
基金Project(50903023) supported by the National Natural Science Foundation of ChinaProject(HEUCF201210005) supported by the Fundamental Research Funds for the Central Universities,ChinaProject(2010RFQXG037) supported by Harbin Special Fund for Innovation Talents of Science and Technology,China
文摘The preparation of TiO2/poly（L-lactide-co-ε-caprolactone）（PLCL） nanocomposites and their properties were reported.TiO2nanoparticles were surface modified by ring-opening polymerization of ε-caprolactone（ε-CL）.The resulting poly（ε-caprolactone）-grafted TiO2（g-TiO2） was characterized by Fourier transform infrared spectroscopy（FTIR）,thermogravimetric analysis（TGA） and transmission electron microscopy（TEM）.The g-TiO2can be uniformly dispersed in chloroform and the g-TiO2/PLCL nanocomposites were successfully fabricated through solvent-casting method.The effects of the content of g-TiO2nanoparticles on tensile properties and shape memory properties were investigated.A significant improvement in the tensile properties of the 5% g-TiO2/PLCL mass fraction nanocomposite is obtained：an increase of 113% in the tensile strength and an increase of 11% in the elongation at break over pure PLCL polymer.The g-TiO2/PLCL nanocomposites with a certain amount of g-TiO2content have better shape memory properties than pure PLCL polymer.The g-TiO2nanoparticles play an additional physical crosslinks which are contributed to improvement of the shape memory properties.
基金Project(2132046)supported by the Beijing Natural Science Foundation,ChinaProject(51104007)supported by the National Natural Science Foundation of China
文摘Ni-Y2O3 nanocomposite powder with uniform distribution of fine oxide particles in the metal matrix was successfully fabricated via solution combustion process followed by hydrogen reduction. The combustion behavior was investigated by DTA-TG analysis. The influence of urea to nickel nitrate（U/Ni） ratio on the combustion behavior and morphology evolution of the combusted powder was investigated. The morphological characteristics and phase transformation of the combusted powder and the reduced powder were characterized by FESEM, TEM and XRD. The HRTEM image of Ni-Y2O3 nanocomposite powder indicated that Y2O3 particles with average particle size of about 10 nm dispersed uniformly in the nickel matrix.
基金Project supported by Research University Grant Scheme (Project A/C No.814004)the Malaysian Technology Development Corporation (MTDC) under the Commercialization of Research and Development Fund (CRDF) (MBF065-USM/05)
文摘An innovative photocatalyst, Carbon nanotube （CNT） supported Ce-TiO2 nanocomposite was successfully synthesized via modi-fied sol gel method and investigated in a batch reactor for abolition of phenol under UV light spectrum. Characterization of catalyst micro-structure and internal properties were done by means of X-ray diffraction （XRD）, Brunauer-Emmett-Teller （BET）, scanning electron micros-copy （SEM）, transmission electron microscopy （TEM） and UV-vis diffuse reflectance spectra （DRS）. Ce doping can inhibit phase transfor-mation from anatase to rutile and eliminate the recombination of electron-hole pairs in the catalyst. The presence of CNT in TiO2 composite can both increase the photoactivity under UV and change surface properties to achieve sensitivity to visible light. The optimum mass ratio of CNT support and cerium （Ce） dopant in TiO2 was the prominent factor to harvest CNT/Ce-TiO2 photocatalyst nanocomposite. The results demonstrated that optimum mass ratio of CNT：TiO2：Ce was 0.02：1.0：0.06, which resulted in the great performance of the photocatalyst to de-grade about 94% of phenol in a 50 mg/L solution in only 3 h. In this paper, dissimilar role of CNT support and Ce dopant in the TiO2 photo-catalysis of phenol was also discussed.
基金supported by National Water Pollution Control and Treatment Science and Technology Major Project(2018ZX07110003)Key Research and Development Project of Shandong Province(2018CXGC1007)~~
文摘A BiOCl-Bi12O17Cl2 nanocomposite with a high visible-light response and a low photoinduced electron-hole pair recombination rate was successfully synthesized using an ultrasonic-hydrothermal method.The texture,structure,optical,and photocatalytic properties of the composite were characterized.The results showed that the composite had a sheet flower-like structure with a large specific surface area.Ultraviolet-visible diffuse reflection spectra and photoluminescence spectra showed that the composite had an excellent visible-light response and a low recombination rate of photoinduced electron hole pairs.The photocatalytic property of the composite was evaluated by the removal efficiency of rhodamine B and ciprofloxacin under visible-light illumination.The composite’s reaction rate constant of removing rhodamine B(/ciprofloxacin)was approximately 8.14(/4.94),42.63(/11.91)and 64.66(/36.07)times that of Bi12O17Cl2,P25,and BiOCl,respectively.Furthermore,the composite showed a wide applicable pH range and excellent reusability.Mechanism analysis showed that photogenerated holes played a dominant role and·O2–also contributed to photocatalytic degradation.In summary,this study presents a high-efficiency photocatalyst for wastewater treatment.
基金EPSRC CDT in Metamaterials at University of Exeter and Leverhulme Trust(RPG-2018-320) for financial support。
文摘Surface-functionalized nitrogen/carbon co-doped polymorphic TiO_(2) phase junction nanoparticles uniformly distributed in porous carbon matrix were synthesized by a simple one-step pyrolysis of titanium based metal-organic framework(MOF),NH_(2)-MIL^(-1)25(Ti) at 700℃ under water vapour atmosphere.Introducing water vapour during the pyrolysis of NH_(2)-MIL^(-1)25(Ti) not only functionalizes the derived porous carbon matrix with carboxyl groups but also forms additional oxygen-rich N like interstitial/intraband states lying above the valence band of TiO2 along with the self-doped carbo n,which further narrows the energy band gaps of polymorphic TiO2 nanoparticles that enhance photocatalytic charge transfer efficiency.Without co-catalyst,sample N-C-TiO2/CArW demonstrates H_(2) evolution activity of 426 μmol gcat-1h^(-1),which remarkably outperforms commercial TiO_(2)(P-25) and N-C-TiO_(2)/CAr with a 5-fold and 3-fold H_(2) generation,respectively.This study clearly shows that water vapour atmosphere during the pyrolysis increases the hydrophilicity of the Ti-MOF derived composites by functionalizing porous carbon matrix with carboxylic groups,as well as enhancing the electrical conductivity and charge transfer efficiency due to the formation of additional localized oxygen-rich N like interstitial/intraband states.This work also demonstrates that by optimizing the anatase-rutile phase composition of the TiO2 polymorphs,tuning the energy band gaps by N/C co-doping and functionalizing the porous carbon matrix in the N-C-TiO2/C nanocomposites,the photocatalytic H_(2) generation activity can be further enhanced.
基金Project supported by UGC-DAE Consortium for Scientific Research,Indore-452 017,India(CSR-KN/CRS-47/2013-14/647)
文摘A simple electrodeposition technique was used to prepare Ni-CeOnanorods composite coating(Ni-CeONRs) using Watt’s nickel plating bath containing CeOnanorods(NRs) as the reinforcement phase under optimized process conditions. The X-ray diffraction analysis(XRD) was used for the structural analysis of Ni-CeONRs composite coatings and their average crystalline size is ～22 nm for pure Ni and ～18 nm,respectively. The crystalline structure is fcc for the Ni-CeOnanocomposite coatings. The surface morphology of the electrodeposited Ni-CeONRs composite coatings was analyzed by scanning electron microscopy(SEM). Microhardness of pure Ni and Ni-CeONRs composite coatings are found to be 253 HV and 824 HV, respectively. The inclusion of CeONRs increases the microhardness of Ni-CeONRs composite coatings. The corrosion resistance behavior of Ni-CeONRs composite coating was evaluated by Tafel polarization and AC impedance methods. It is revealed that CeONRs reinforced Ni matrix shows higher microhardness and corrosion resistance than existing reported electrodeposited pure Ni and CeOnanoparticles reinforced Ni coatings.
基金financially supported by the University of Tabriz
文摘Surface of TiO2 nanoparticles was modified with the in situ chemical oxidative polymerization of aniline. Polyaniline modified TiO2 nanoparticles （PANI-TiO2） were characterized with the FT-IR, XRD, SEM and TEM techniques. Results confirmed that PANI was grafted successfully on the surface of TiO2 nanoparticles, therefore agglomeration of nanoparticles decreased dramatically. Polyvinyl chloride nanocomposites filled with 1 wt%-5 wt% of PANI-TiO2 and TiO2 nanoparticles were prepared via the solution blending method. PVC nanocomposites were analyzed with FT-IR, XRD, SEM, TG/DTA, DSC and tensile test techniques. Effect of PANI as surface modifier of nanoparticles was discussed according to the final properties of PVC nanocomposites. Results demonstrated that deposition of PANI on the surface of TiO2 nanoparticles improved the interfacial adhesion between the constituents of nanocomposites, which resulted in better dispersion of nanoparticles in the PVC matrix. Also PVC/PANI-TiO2 nanocomposites showed higher thennal resistance, tensile strength and Young＇s modulus compared to those of unfilled PVC and PVC/TiO2 nanocomposites.
文摘Ag/TiO2/freeze-dried graphene nanocomposites have been prepared via a facile one-step solvothermal method for the photocatalytic degradation of Rh B under visible light irradiation. During the solvothermal process, reduction of graphene oxide and loading of Ag/TiO2nanoparticles on graphene sheets were achieved. Investigation of chemical state of products showed that covering of Ag/TiO2surface with higher weight ratio of graphene resulting in that Ag metals in Ag/TiO2were oxidized to Ag2 O in nanocomposite structure after solvothermal process. Degree of photocatalytic activity enhancement strongly depends on the coverage of Ag/TiO2surface by porous graphene. The sample of 1 wt% porous graphene hybridized Ag/TiO2showed the highest photocatalytic activity, which is related to high migration efficiency of photoinduced of electrons and reduction of electron–hole recombination rate due to high electrical conductivity of graphene. Expanding of absorption to visible light region was ascribed to surface plasmon resonance effect of Ag metals and presence of graphene. Investigation of photocatalytic performance of formic acid as a dye-less organic pollutant showed that dye sensitization effect of Rh B molecules during evaluation of photocatalytic performance was negligible.
文摘A series of La2O3/MC nylon nanocomposites were prepared via in situ polymerization. The effects of content of nano-La2O3 on the mechanical properties of nanocomposites were studied. Dispersion of nano-La2O3 in MC nylon matrix was observed with SEM. The crystal structure of nanocomposites was characterized by means of XRD. SEM analysis shows that La2O3 nanoparticles are uniformly dispersed in MC nylon matrix and little clustering exists when the content of nano- La2O3 is lower than 1%, however, when the content of nano-La2O3 is more than 1%, it begins to cluster. XRD analysis indicats that nano-La2O3 does not change the crystal structure of MC nylon. Mechanical properties tests show that the tensile strength, elongation at break, impact strength, flexural strength, and flexural modulus of nanocomposites first increase then decrease as the content of nano-La2O3 is increased. When the content of nano-La2O3 is 0.5%, the tensile strength and elongation at break of nanocomposites reach maximum, which are 17.9% and 52.1% higher respectively than those of MC nylon. When the content of nano-La2O3 is 1.0%, the impact strength, flexural strength and flexural modulus of nanocomposites reach maximum, which are 36.6 %, 12.7 % and 16.3 % higher respectively than those of MC nylon.
文摘In this investigation, polymeric nanocomposite membranes（PNMs） were prepared via incorporating zinc oxide（ZnO） into poly（ether-block-amide）(PEBAX-1074) polymer matrix with different loadings. The neat membrane and nanocomposite membranes were prepared via solution casting and solution blending methods, respectively. The fabricated membranes were characterized by field emission scanning electron microscopy（FESEM） to survey cross-sectional morphologies and thermal gravimetric analysis（TGA）to study thermal stability. Fourier transform infrared（FT-IR） and X-ray diffraction（XRD） analyses were also employed to identify variations of the chemical bonds and crystal structure of the membranes, respectively. Permeation of pure gases, CO, CHand Nthrough the prepared neat and nanocomposite membranes was studied at pressures of 3–18 bar and temperature of 25 °C. The obtained results showed that the fabricated nanocomposite membranes exhibit better separation performance compared to the neat PEBAX membrane in terms of both permeability and selectivity. As an example, at temperature of 25 °C and pressure of 3 bar, COpermeability, ideal CO/CHand CO/Nselectivity values for the neat PEBAX membrane are 110.67 Barrer, 11.09 and 50.08, respectively, while those values are 152.27 Barrer,13.52 and 62.15 for PEBAX/ZnO nanocomposite membrane containing 8 wt% ZnO.
基金EPSRC CDT in Metamaterials at the University of Exeter and Leverhulme Trust(RPG-2018-320)for financial support。
文摘Multi-functionalized and co-doped TiO_(2)/C nanocomposites were derived from the pyrolysis of Ti-MOFs at 800℃under different gaseous atmospheres and their photocatalytic performance were investigated.The gaseous atmosphere during pyrolysis plays a critical role in determining the structural,textural,optical and physicochemical properties of the derived TiO_(2)/C composites due to the synergistic effect of nitrogen-containing species,carboxylate and sulfur functionalized porous carbon as well as N/S co-doped TiO_(2)nanoparticles.All the Ti-MOFs derived TiO_(2)/C composites exclusively possess homogeneously distributed TiO_(2)nanoparticles in a functionalized disc-like porous carbon matrix and demonstrate much enhanced adsorption and photodegradation performance than commercial TiO_(2)under the same conditions.The adsorption of methylene blue(MB)in dark on these TiO_(2)/C composites are dominated with pseudo second-order kinetic model and the high adsorption capacity of MB in dark on composite TiO_(2)/C derived from MIL-125(Ti)in argon is due to its high surface area with predominant mesoporous carbon matrix in the composite.The composite N-O-TiO_(2)/C derived from NH2-MIL-125(Ti)in water vapor exhibited the highest photodegradation activity with 99.7%MB removal in 3 h under visible light due to the optimal anatase/rutile phasejunction,together with the formation of photoactive oxygen-rich N-O like interstitial/intraband states above the valence band of TiO_(2),as well as the presence of N-containing species and-OH/-COOH multi-functional groups with superhydrophilic nature of the composite.This simple one-step and easily modifiable approach can be further employed to modulate homogeneously dispersed multi-functionalized and co-doped metal oxide/carbon nanocomposites for various environment and energy-related applications.
基金supported by Zhejiang Provincial Natural Science Foundation of China (No. LY18F010009)Ningbo Natural Science Foundation (No. 2018A610002)
文摘Two-dimensional(2D)nanomaterials have demonstrated great potential in the field of flexible gas sensing due to their inherent high specific surface areas,unique electronic properties and flexibility property.However,numerous challenges including sensitivity,selectivity,response time,recovery time,and stability have to be addressed before their practical application in gas detection field.Development of graphene-like 2D/2D nanocomposites as an efficient strategy to achieve high-performance 2D gas sensor has been reported recently.This review aims to discuss the latest advancements in the 2D/2D nanocomposites for gas sensors.We first elaborate the gas-sensing mechanisms and the collective benefits of 2D/2D hybridization as sensor materials.Then,we systematically present the current gas-sensing applications based on different categories of 2D/2D nanocomposites.Finally,we conclude the future prospect of 2D/2D nanocomposites in gas sensing applications.
基金Supported by the National Basic Research Program of China("973"Program,No.2014CB239300,No.2012CB720100)National Natural Science Foundation of China(No.21406164,No.21466035)Specialized Research Fund for the Doctoral Program of Higher Education of China(No.20110032110037,No.20130032120019)
文摘An efficient visible-light-responsive BiOBr/TiO2 heterojunction nanocomposite was fabricated successfully using in-situ depositing technique at room temperature by introducing BiOBr onto the surface of TiO2 nano- belts pre-prepared by hydrothermal reaction and etched with H2SO4. The obtained particles were characterized by XRD, SEM, TEM, XPS, UV-Vis DRS and PL techniques. BiOBr/TiO2 heterojunction nanocomposites with different mass ratios of m （BiOBr）/m （TiO2） were discussed in order to get the best photocatalytie activity, and BiOBr/TiO2-1.0 was proved to be the optimal mass ratio. BiOBr/TiO2-1.0 exhibited excellent photocatalytic activity in the degradation of RhB compared with TiO2 nanobelts, pure BiOBr and the mechanical mixture of TiO2 nanobelts and BiOBr. At last, a possible mechanism ofphotocatalytic enhancement was proposed.
基金financial support of National Research Foundation and effort by the Surface Engineering Research Centre (SERC)
文摘In this study, for marine application purposes, we evaluated the effect of process parameter and particle loading on the microstructure, mechanical reinforcement and corrosion resistance properties of a Zn-TiO2-WO3 nanocomposite produced via electrodeposition. We characterized the morphological properties of the composite coatings with a Scanning Electron Microscope （SEM） equipped with an Energy Dispersive Spectrometer （EDS）. We carried out mechanical examination using a Dura Scan hardness tester and a CERT UMT-2 multi-functional tribological tester. We evaluated the corrosion properties by linear polarization in 3.5% NaCl. The results show that the coatings exhibited good stability and the quantitative particle loading greatly enhanced the structural and morphological properties, hardness behavior and corrosion resistance of the coatings. We observed the precipitation of this alloy on steel is greatly influenced by the composite characteristics.
基金supported in part by the National Natural Science Foundation of China(Grant Nos.51677120 and 51207093)the Shenzhen Government Fund(Grant Nos.JCYJ20160422102919963)the Shenzhen Key Laboratory of Special Functional Materials(Grant Nos.T201502)
文摘In this work, a series of Cu2O-Ag/ZnO, Cu2O/ZnO and Ag/ZnO nanocomposites with various compositions were prepared via a hydrothermal method followed by chemical modification, and their antibacterial performance was investigated in detail. X-ray powder diffraction, scanning electron microscopy and transmission electron microscopy results confirmed that 31 nm Cu20 and 30 nm Ag nanoparticles are well-dispersed on 202 nm ZnO grains to form a Cu2O/ZnO and Ag/ZnO heterojunction, respectively. The bi-heterojuction structure in the Cu20-Ag/ZnO provided a synergistic effect on antibacterial activity, and the(Cu2O)0.04Ag0.06ZnO0.9nanocomposites showed the highest antimicrobial activity of all samples with minimum inhibitory concentration and minimum bactericidal concentration against Escherichia coli and Staphylococcus aureus as low to 31.25 μg/mL, 250μg/mL, 125μg/mL and 500μg/mL, respectively. This is the first report of the antibacterial activities of Cu2O and Ag co-modified ZnO nanocomposites.
