Photothermal synergistic catalytic systems for treating volatile organic compounds(VOCs)have attracted signif-icant attention due to their energy efficiency and potential to reduce carbon emissions.However,the mechani...Photothermal synergistic catalytic systems for treating volatile organic compounds(VOCs)have attracted signif-icant attention due to their energy efficiency and potential to reduce carbon emissions.However,the mechanism underlying the synergistic reaction remains a critical issue.This study introduces a photothermal synergistic system for the removal of ethyl acetate(EA)by synthesizing Cu-doped OMS-2(denoted as Cu-OMS-2).Under ultraviolet-visible(UV–Vis)irradiation in a flow system,the Cu-OMS-2 catalyst exhibited significantly enhanced performance in the EA degradation process,nearly doubling the effectiveness of pure OMS-2,and increasing carbon dioxide yield by 20%.This exceptional performance is attributed to the synergistic effect of increased oxygen vacancies(OV)at OMS-2 active sites and Cu doping,as confirmed by H2-TPR,O_(2)-TPD,and CO consump-tion measurements.This study clarifies the catalytic mechanism of light-assisted thermocatalysis and offers a novel strategy for designing photothermal catalysts with homogeneous Cu-doped nanorods for VOC removal.展开更多
Cu-doped borate glass co-doped with SnO2nanoparticles is fabricated by melt quenching.The structure and morphology of the samples are examined by X-ray diffraction and field emission scanning electron microscopy.Up-co...Cu-doped borate glass co-doped with SnO2nanoparticles is fabricated by melt quenching.The structure and morphology of the samples are examined by X-ray diffraction and field emission scanning electron microscopy.Up-conversion enhancement is observed in the photoluminescence（PL） and thermoluminescence（TL） intensities of the glass.PL emission spectra are identified in the blue and green regions,and a fourfold increase in emission intensity may be observed in the presence of embedded SnO2nanoparticles.The glow curve is recorded at 215 C,and fourfold increases in TL intensity are obtained by addition of 0.1 mol% SnO2nanoparticles to the glass.Higher TL responses of the samples are observed in the energy range of 15-100 KeV.At energy levels greater than;.1 MeV,however,flat responses are obtained.The activation energy and frequency factor of the second-order kinetic reaction are calculated by the peak shape method.展开更多
InP quantum dots(QDs)have been a major building block of modern display technology due to their high photoluminescence quantum yield(PLQY)in the visible spectrum,superior stability,and eco-friendly composition.However...InP quantum dots(QDs)have been a major building block of modern display technology due to their high photoluminescence quantum yield(PLQY)in the visible spectrum,superior stability,and eco-friendly composition.However,their applications at short-wave infrared(SWIR)have been hindered by their low efficiency.Here,we report the synthesis of efficient and SWIR-emitting InP QDs by precisely controlling the InP core nucleation using a low-cost ammonia phosphorus precursor,while avoiding size-limiting ZnCl_(2) for effective copper doping.Subsequent epitaxial growth of a lattice-matched ZnSe/ZnS multishell enhanced the QD sphericity and surface smoothness and yielded a record PLQY of 66% with an emission peak at 960 nm.When QDs were integrated as the high-refractive-index luminescent core of a liquid waveguide-based luminescent solar concentrator(LSC),the device achieved an optical efficiency of 7.36%.This performance arises from their high PLQY,spectral alignment with the responsivity peak of silicon solar cells,and the optimized core/cladding waveguide structure.These results highlight the potential of InP QDs as a promising nanomaterial for SWIR emission and applications.展开更多
The reasonable employment of cocatalyst in photocatalysis can effectively promote the photocatalytic H_(2)production activity.In this study,carbon hollow spheres(C),as a good conductive nonmetallic material,have been ...The reasonable employment of cocatalyst in photocatalysis can effectively promote the photocatalytic H_(2)production activity.In this study,carbon hollow spheres(C),as a good conductive nonmetallic material,have been utilized as a novel cocatalyst and a matrix for loading the Cu-doped-TiO_(2)nanoparticles by a successive hydrother-mal method and metal molten salt method.The Cu-doped-TiO_(2)nanoparticles were tightly anchored on the surface of carbon hollow sphere to form a zero-dimensional/three dimensional(0D/3D)Cu-doped-TiO2/C heterojunction.The optimal Cu-doped-TiO_(2)/C heterojunction demon-strated greatly enhanced photocatalytic H_(2) generation activity(14.4 mmol·g^(-1)·h^(-1))compared with TiO_(2)(0.33 mmol·g^(-1)·h^(-1))and TiO_(2)/C(0.7 mmol·g^(-1)·h^(-1)).The performance improvement was mainly due to the syner-gistic effect of carbon hollow sphere cocatalyst and Cu-doping,the Cu-doping in TiO_(2)nanoparticles can minimize charge recombination and enhance the available photoex-cited electrons,while the 3D carbon hollow spheres can act as electron traps to accelerate the charge separation and offer abundant active sites for solar water splitting reaction.展开更多
Zn0.99Cu0.01O films were studied experimentally and theoretically. The films were prepared by pulsed-laser deposition on Pt（111）/Ti/SiO2/Si substrates under various oxygen pressures to investigate the growth-depende...Zn0.99Cu0.01O films were studied experimentally and theoretically. The films were prepared by pulsed-laser deposition on Pt（111）/Ti/SiO2/Si substrates under various oxygen pressures to investigate the growth-dependence of the ferromagnetic properties. The structural, magnetic, and optical properties were studied, and it was found that all the samples possess a typical wurtzite structure, and that the films exhibit room-temperature ferromagnetism. The sample deposited at 600 ℃ and an oxygen pressure of 10 Pa showed a large saturation magnetization of 0.83 μB/Cu. The enhanced ferromagnetism in the （Cu, Li）-codoped ZnO is attributable to the existence of Zn vacancies （Vzn）, as shown by first-principles calcu- lations. The photoluminescence analysis demonstrated the existence of Vzn in both Zn0.99Cu0.01 O and （Cu, Li）-codoped ZnO thin films, and this plays an important role in the increase of ferromagnetism, according to the results of first-principles calculations.展开更多
The multiple metal catalyst as a promising nanomaterial has shown excellent activity in the peroxymonosulfate(PMS)activation for pollutant degradation.However,the role of special sites and in-depth understanding of th...The multiple metal catalyst as a promising nanomaterial has shown excellent activity in the peroxymonosulfate(PMS)activation for pollutant degradation.However,the role of special sites and in-depth understanding of the PMS activation mechanism are not fully studied.In this study,a Cu-doped CoFe_(2)O_(4)nanocatalyst(0.5CCF)was synthesized by a sol-gel and calcination method,and used for PMS activation to remove Rhodamine B(RhB).The results showed that the Cu doping obviously enhanced the catalytic performance of CoFe_(2)O_(4),with 99.70%of RhB removed by 0.5CCF while 74.91%in the CoFe_(2)O_(4)within 15 min.Based on the X-ray photoelectron spectroscopy and electrochemical analysis,this could be ascribed to the more low valence of Co and Fe species generated on the 0.5CCF and faster electron transfers occurred in the 0.5CCF due to the Cu doping.In addition,Cu doping could provide more reaction sites for the 0.5CCF to activate PMS for RhB removal.The metal species and the surface hydroxyl were the reaction sites of PMS activation,and the surface hydroxyl played an important role in surface-bound reactive species generation.During the PMS activation,the Cu not only activated PMS to produce reactive oxygen species(ROS),but also regenerated Co^(2+)and Fe^(2+)to accelerate the PMS activation.The non-radical of ^(1)O_(2)was the main ROS with a 99.35%of contribution rate,and the SO_(5)^(·–)self-reaction was its major source.This study provides a new insight to enhance the PMS activation performance of multiple metal catalysts by Cu doping in wastewater treatment.展开更多
The synthesis of Cu-doped ZnO nanosheets at room temperature was reported in our previous paper. The effects of annealing temperature on Cu-doped ZnO nanosheets were studied in this paper. Cu-doped ZnO nanosheets were...The synthesis of Cu-doped ZnO nanosheets at room temperature was reported in our previous paper. The effects of annealing temperature on Cu-doped ZnO nanosheets were studied in this paper. Cu-doped ZnO nanosheets were annealed at 200-500℃ in air. The annealed specimens were characterized by scanning electron microscopy （SEM）, X-ray diffraction （XRD） and transmission electron microscopy （TEM）. The results show that Cu concentration in Cu-doped ZnO nanosheets reduced with increasing annealing temperature. When annealing temperature was lower than Zn melting point （410℃）, the morphologies of the Cu-doped ZnO nanosheets remained nearly the same as that before annealing. However, when the annealing temperature was over Zn melting point, Cu-doped ZnO nanosheets changed to nanowires, wormlike nanosheets or did not change. The change of Cu concentration in Cu-doped ZnO nanosheets is explained by oxidation thermodynamics. A physical model is suggested to explain the morphology changes of Cu-doped ZnO nanosheets, based on the existence of Cu-rich layer beneath Cu-doped ZnO nanosheets.展开更多
Copper （Cu）-doped ZrO2 （CZO） films with different Cu content （0 at.%- 8.07 at.%） are successfully deposited on Si （100） substrates by direct current （DC） and radio frequency （RF） magnetron co-sputtering. T...Copper （Cu）-doped ZrO2 （CZO） films with different Cu content （0 at.%- 8.07 at.%） are successfully deposited on Si （100） substrates by direct current （DC） and radio frequency （RF） magnetron co-sputtering. The influences of Cu content on structural, morphological, optical and electrical properties of CZO films are discussed in detail. The CZO films exhibit ZrO2 monocline （1^-11） preferred orientation, which indicates that Cu atoms are doped in ZrO2 host lattice. The crystallite size estimated form x-ray diffraction （XRD） increases by Cu doping, which accords with the result observed from the scanning electron microscope （SEM）. The electrical resistivity decreases from 2.63 Ω·cm to 1.48 Ω·cm with Cu doping content increasing, which indicates that the conductivity of CZO film is improved. However, the visible light transmittances decrease slightly by Cu doping and the optical band gap values decrease from 4.64 eV to 4.48 eV for CZO fihns.展开更多
Hole carrier mediated magnetization in Cu-doped GaN is investigated by using the first-principles calculations. By studying the sp-d interaction and the direct exchange interaction among the dopants, we obtain an equa...Hole carrier mediated magnetization in Cu-doped GaN is investigated by using the first-principles calculations. By studying the sp-d interaction and the direct exchange interaction among the dopants, we obtain an equation to determine the spontaneous magnetization as a function of the Cu dopant concentration and the hole carrier density. It is demonstrated that nonmagnetic Cu doped GaN can be of room-temperature ferromagnetism. The system＇s Curie temperature Tc can reach about 345 K with Cu concentration of 1.0% and hole carrier density of 5.0×10^19 cm-3. The results are in good agreement with experimental observations and indicate that ferromagnetism in this systems is tunable by controlling the Cu concentration and the hole carrier density.展开更多
An atmospheric-pressure dielectric barrier discharge （DBD） gas-liquid cold plasma was employed to synthesize Cu-doped TiO~ nanoparticles in an aqueous solution with the assistance of [C2MIM]BF4 ionic liquid （IL） a...An atmospheric-pressure dielectric barrier discharge （DBD） gas-liquid cold plasma was employed to synthesize Cu-doped TiO~ nanoparticles in an aqueous solution with the assistance of [C2MIM]BF4 ionic liquid （IL） and using air as the working gas. The influences of the discharge voltage, IL and the amount of copper nitrite were investigated. X-ray diffraction, N2 adsorption-desorption measurements and UV-Vis spectroscopy were adopted to characterize the samples. The results showed that the specific surface area of TiO2 was promoted with Cu-doping （from 57.6 m^2.g^-1 to 106.2 m^2.g^-1 with 3% Cu-doping）, and the content of anatase was increased. Besides, the band gap energy of TiO~ with Cu-doping decreased according to the UV-Vis spec- troscopy test. The 3%Cu-IL-TiO2 samples showed the highest eificiency in degrading methylene blue （MB） dye solutions under simulated sunlight with an apparent rate constant of 0.0223 min-1, which was 1.2 times higher than that of non-doped samples. According to the characterization results, the reasons for the high photocatalytic activity were discussed.展开更多
In this paper, photorefractive crystals of Cu-doped (K0.5Na0.5)0.2 (Sr0.75Ba0.25)0.9Nb2O6 (KNSBN) are systematically studied. A series of Cu-doped KNSBN crystals have been grown and the samples with Cu-dopant in diffe...In this paper, photorefractive crystals of Cu-doped (K0.5Na0.5)0.2 (Sr0.75Ba0.25)0.9Nb2O6 (KNSBN) are systematically studied. A series of Cu-doped KNSBN crystals have been grown and the samples with Cu-dopant in different levels and thicknesses have been fabricated. Their photorefractive properties including two-wave coupling gain coefficients and response rate are experimentally studied in details. The results show that (1) with high Cudopant cocentration, the crystal has larger coupling gain coefficient, higher effective charge carrier density, and faster time response; (2) thinner sample shows larger coupling gain coefficientl (3) at shorter wavelength 9 the crystal sample shows larger coupling gain coefficient and faster time response. The Cu-doping mechanisms were briefly referred. The analyses of the relationships among the crystal’s two-wave coupling, absorption property and the self-pumped phase conjugation are given. All the results show that Cu-doped KNSBN crystals are a kind of very promising photorefractive materials.展开更多
Zn（1-x）Cux O（x=0.00, 0.01, 0.03, and 0.05） nanoparticles are synthesized via the sol-gel technique using gelatin and nitrate precursors. The impact of copper concentration on the structural, optical, and antibacte...Zn（1-x）Cux O（x=0.00, 0.01, 0.03, and 0.05） nanoparticles are synthesized via the sol-gel technique using gelatin and nitrate precursors. The impact of copper concentration on the structural, optical, and antibacterial properties of these nanoparticles is demonstrated. Powder x-ray diffraction investigations have illustrated the organized Cu doping into ZnO nanoparticles up to Cu concentration of 5%（x = 0.05）. However, the peak corresponding to CuO for x= 0.01 is not distinguishable. The images of field emission scanning electron microscopy demonstrate the existence of a nearly spherical shape with a size in the range of 30–52 nm. Doping Cu creates the Cu–O–Zn on the surface and results in a decrease in the crystallite size. Photoluminescence and absorption spectra display that doping Cu causes an increment in the energy band gap. The antibacterial activities of the nanoparticles are examined against Escherichia coli（Gram negative bacteria）cultures using optical density at 600 nm and a comparison of the size of inhibition zone diameter. It is found that both pure and doped ZnO nanoparticles indicate appropriate antibacterial activity which rises with Cu doping.展开更多
Porous Cu-doped SnO<sub>2</sub> thin films were synthesized by the sol-gel dip-coating method for enhancing methanol sensing performance. The effect of Cu doping concentration on the SnO<sub>2</su...Porous Cu-doped SnO<sub>2</sub> thin films were synthesized by the sol-gel dip-coating method for enhancing methanol sensing performance. The effect of Cu doping concentration on the SnO<sub>2</sub> sensibility was investigated. XRD data confirm that the fabricated SnO<sub>2</sub> films are polycrystalline with tetragonal rutile crystal structure. AFM and SEM micrographs confirmed the roughness and the porosity of SnO<sub>2</sub> surface, respectively. UV-Vis spectrum shows that SnO<sub>2</sub> thin films exhibit high transmittance in the visible region ~95%. The band gap (3.80 - 3.92 eV) and the optical thickness (893 - 131 nm) of prepared films were calculated from transmittance data. The sensing results demonstrate that SnO<sub>2</sub> films have a high sensitivity and a fast response to methanol. In particular, 3% Cu-SnO<sub>2</sub> films have a higher sensitivity (98%), faster response (10-<sup>2</sup> s) and shorter recovery time (18 s) than other films.展开更多
Silver nanowires(Ag NWs)have promising application potential in electronic displays because of their superior flexibility and transparency.Doping Ni in Ag NWs has proven to be an effective strategy to im-prove its wor...Silver nanowires(Ag NWs)have promising application potential in electronic displays because of their superior flexibility and transparency.Doping Ni in Ag NWs has proven to be an effective strategy to im-prove its work function.However,AgNi NWs-based electrodes suffer from poor electrical conductivity under air exposure due to the low-conductivity NiO generated on its surface.Here,Cu was further doped in AgNi NWs to form AgNiCu NWs and regulate its surface oxide under long-term air exposure.Finally,it is demonstrated that the conductivity of AgNiCu NWs can acquire an improved tolerable tempera-ture(over 240℃)and prolonged high-temperature tolerance time(over 150 min)by finely regulating the doping content Cu,indicating an enhanced air-stable conductivity.The optimized AgNiCu NWs also achieve superior transparent conductivity as pure Ag NWs and high work function as AgNi NWs,which has been successfully applied in constructing an n-type photodiode with an effective rectification effect.展开更多
This study addresses the challenge of high sintering temperatures in proton-conducting fuel cells(PCFCs)with BaCeO_(3)-doped electrolytes.We demonstrate that 1 mol%copper(Cu)doping at the B-site of BaCe_(0.7)Zr_(0.1)(...This study addresses the challenge of high sintering temperatures in proton-conducting fuel cells(PCFCs)with BaCeO_(3)-doped electrolytes.We demonstrate that 1 mol%copper(Cu)doping at the B-site of BaCe_(0.7)Zr_(0.1)(Dy_(0.1)|Yb_(0.1))_(0.2)O_(3-δ)(BCZDYb)improves sintering behavior,enabling densification at1400℃.However,Cu doping disrupts stoichiometry,creating barium vacancies and reducing protonaccepting cations,affecting overall conductivity.This mechanism is confirmed through density functional theory(DFT)calculations and various experimental techniques,including crystal structure analysis using X-ray diffraction(XRD)and morphology and elemental analysis via field emission scanning electron microscopy(FESEM)and energy-dispersive X-ray spectroscopy(EDS).Electrochemical measurements are performed using the electrochemical impedance spectroscopy(EIS).The ionic conductivity of1 mol%Cu-doped BCZDYb(BCZDYb-1)is 1.49×10^(-2)S cm^(-1)at 650℃,which is~3.58 times higher than that of BCZDYb sintered at 1200℃.The BCZDYb-1 exhibits~16 times higher grain boundary conductivity when sintered at 1400℃,compared to undoped BCZDYb.The single cell employing BCZDYb-1 as the electrolyte achieved a power density of~606 mW cm^(-2)at 550℃.These results indicate that a controlled amount of Cu doping can enhance densification while maintaining high ionic co nductivity,making it suitable for practical applications in PCFCs operating at lower temperatures.展开更多
The Ln_(2)NiO_(4+δ)-based layered phases have attracted much attention as components for high-performance protonic ceramic fuel cells(PCFCs)and electrolysis cells(PCECs)enabling energy conversion with good efficiency...The Ln_(2)NiO_(4+δ)-based layered phases have attracted much attention as components for high-performance protonic ceramic fuel cells(PCFCs)and electrolysis cells(PCECs)enabling energy conversion with good efficiency and low pollution.The present paper aims at rationally engineering the Cu-doped Pr_(2)NiO_(4+δ)materials and analysing their electrode behaviour for reversible protonic ceramic cells operating in both PCFC and PCEC modes.Complex oxides of Pr_(2)Ni_(1-x)CuxO_(4+δ)(x=0,0.1,0.2 and 0.3)were synthesised using the citrate-nitrate method.The obtained materials were characterised considering their crystalline structures,as well as thermal,thermomechanical and electrotransport properties.A special interest was focused on the quality of an electrode/electrolyte interface governing the electrochemical performance of the cells fabricated.It is shown that a copper doping of x=0.2 has a positive impact on the thermomechanical compatibility of the Ba(Ce,Zr)O_(3)-based electrolytes,providing a better adhesion to these electrolytes at low-temperature sintering and resulting in a decrease of the polarisation resistance of the air electrodes.A reversible protonic ceramic cell demonstrates a power density of~340 m W cm^(-2) and a hydrogen output flux of~3.8 ml cm^(-2) min^(-1) at 750℃.The presented results propose modernised alkaline-earth-element-free and cobalt-free electrodes that can be successfully used in the electrochemical cells based on the-state-of-the-art proton-conducting electrolytes.展开更多
The Zn1-xCuxO polycrystalline materials were prepared by doping CuO into wurtzite ZnO through solid state reaction. The high concentration of copper doping in ZnO exhibited remarkable room temperature ferromagnetism. ...The Zn1-xCuxO polycrystalline materials were prepared by doping CuO into wurtzite ZnO through solid state reaction. The high concentration of copper doping in ZnO exhibited remarkable room temperature ferromagnetism. The Experiments showed that the magnetization saturation rose with the increase of Cu content. For the low Cu content sample, the hysteresis loop was slightly tilted which indicated that the diamagnetism coexisted in this sample. The temperature dependence of magnetization of Zn1-xCuxO revealed that the magnetic exchange coupling depended on the doping concentration of Cu and there were many different local environments for magnetism. The measured hysteresis loop and temperature dependence of magnetization were overall performance of the magnetism coming from a wide distribution of ferromagnetic exchange couplings.展开更多
Photo-induced self-healing composites have attracted more and more attention as a kind of materials that can be controlled remotely and accurately in real time.Here,we report a strategy of a photo-responsive system ba...Photo-induced self-healing composites have attracted more and more attention as a kind of materials that can be controlled remotely and accurately in real time.Here,we report a strategy of a photo-responsive system based on hydrogen and ion bonds capable of performing self-healing process by ultraviolet wave-lengths,which is covalently cross-linked zinc-dimethylglyoxime-polyurethane coordination network with triple dynamic bonds.The recombination of hydrogen bond and metal coordination bond produces ef-fective healing performance.The self-healing behavior and temperature dependence of 3D micro-crack is investigated by molecular dynamics simulations to reveal the mechanism of self-healing at molecu-lar level.Moreover,the hybrid of copper-doped zinc oxide not only provides metal coordination bonds to enhance the self-healing rate,but also enhances the photothermal effect and anti-bacterial properties of polyurethane.Importantly,doping of copper generates more defects and forms a space charge layer on the surface of zinc oxide.The defects could trap surface electrons and holes,preventing the recom-bination of photo-induced electron-hole pairs,generating more heat through lattice vibration.Therefore,under ultraviolet light irradiation,the polyurethane can reach 62.7°C for 60 s,and the scratches of the polyurethane can be healed within 30 min and fully healed within 1 h.展开更多
The nano-nickel hydroxide samples were prepared by means of ultrasonic-assisted precipitation and the impact of source/doping element/buffer on the structure of Ni（OH）： was studied. The results of XRD, IR and TEM t...The nano-nickel hydroxide samples were prepared by means of ultrasonic-assisted precipitation and the impact of source/doping element/buffer on the structure of Ni（OH）： was studied. The results of XRD, IR and TEM testing clearly revealed that larger anionic radius of the nickel sources or the buffer solution was conducive to the formation of α-Ni（OH）2. The proportion of α-Ni（OH）： samples doped with two elements was larger than that doped with single element. Additionally, speciation, valence as well as the radius of doping ions can directly affect the phase of Ni（OH）2.展开更多
We perform a first-principles simulation to study the electronic and optical properties of wurtzite Zn1-xCuxO. The simulations are based upon the Perdew-Burke-Ernzerhof form of generalised gradient approximation withi...We perform a first-principles simulation to study the electronic and optical properties of wurtzite Zn1-xCuxO. The simulations are based upon the Perdew-Burke-Ernzerhof form of generalised gradient approximation within the density functional theory. Calculations are carried out in different concentrations. With increasing Cu concentration, the band gap of Znl-xCuxO decreases due to the shift of valence band. The imaginary part of the dielectric function indicates that the optical transition between O2p states in the highest valence band and Zn 4s states in the lowest conduction band shifts to the low energy range as the Cu concentration increases. Besides, it is shown that the insertion of Cu atom leads to redshift of the optical absorption edge. Meanwhile, the optical constants of pure ZnO and Zn0.75Cu0.250, such as loss function, refractive index and reflectivity, are discussed.展开更多
基金supported by the Qilu University of Technology(Shandong Academy of Sciences),the Basic Research Project of Science,Education and Industry Integration Pilot Project(No.2022PY047).
文摘Photothermal synergistic catalytic systems for treating volatile organic compounds(VOCs)have attracted signif-icant attention due to their energy efficiency and potential to reduce carbon emissions.However,the mechanism underlying the synergistic reaction remains a critical issue.This study introduces a photothermal synergistic system for the removal of ethyl acetate(EA)by synthesizing Cu-doped OMS-2(denoted as Cu-OMS-2).Under ultraviolet-visible(UV–Vis)irradiation in a flow system,the Cu-OMS-2 catalyst exhibited significantly enhanced performance in the EA degradation process,nearly doubling the effectiveness of pure OMS-2,and increasing carbon dioxide yield by 20%.This exceptional performance is attributed to the synergistic effect of increased oxygen vacancies(OV)at OMS-2 active sites and Cu doping,as confirmed by H2-TPR,O_(2)-TPD,and CO consump-tion measurements.This study clarifies the catalytic mechanism of light-assisted thermocatalysis and offers a novel strategy for designing photothermal catalysts with homogeneous Cu-doped nanorods for VOC removal.
基金RMC, UTM for providing research funding to complete this work
文摘Cu-doped borate glass co-doped with SnO2nanoparticles is fabricated by melt quenching.The structure and morphology of the samples are examined by X-ray diffraction and field emission scanning electron microscopy.Up-conversion enhancement is observed in the photoluminescence（PL） and thermoluminescence（TL） intensities of the glass.PL emission spectra are identified in the blue and green regions,and a fourfold increase in emission intensity may be observed in the presence of embedded SnO2nanoparticles.The glow curve is recorded at 215 C,and fourfold increases in TL intensity are obtained by addition of 0.1 mol% SnO2nanoparticles to the glass.Higher TL responses of the samples are observed in the energy range of 15-100 KeV.At energy levels greater than;.1 MeV,however,flat responses are obtained.The activation energy and frequency factor of the second-order kinetic reaction are calculated by the peak shape method.
文摘InP quantum dots(QDs)have been a major building block of modern display technology due to their high photoluminescence quantum yield(PLQY)in the visible spectrum,superior stability,and eco-friendly composition.However,their applications at short-wave infrared(SWIR)have been hindered by their low efficiency.Here,we report the synthesis of efficient and SWIR-emitting InP QDs by precisely controlling the InP core nucleation using a low-cost ammonia phosphorus precursor,while avoiding size-limiting ZnCl_(2) for effective copper doping.Subsequent epitaxial growth of a lattice-matched ZnSe/ZnS multishell enhanced the QD sphericity and surface smoothness and yielded a record PLQY of 66% with an emission peak at 960 nm.When QDs were integrated as the high-refractive-index luminescent core of a liquid waveguide-based luminescent solar concentrator(LSC),the device achieved an optical efficiency of 7.36%.This performance arises from their high PLQY,spectral alignment with the responsivity peak of silicon solar cells,and the optimized core/cladding waveguide structure.These results highlight the potential of InP QDs as a promising nanomaterial for SWIR emission and applications.
基金financially supported by the National Natural Science Foundation of China (Nos.21975110 and 21972058)Taishan Youth Scholar Program of Shandong Province
文摘The reasonable employment of cocatalyst in photocatalysis can effectively promote the photocatalytic H_(2)production activity.In this study,carbon hollow spheres(C),as a good conductive nonmetallic material,have been utilized as a novel cocatalyst and a matrix for loading the Cu-doped-TiO_(2)nanoparticles by a successive hydrother-mal method and metal molten salt method.The Cu-doped-TiO_(2)nanoparticles were tightly anchored on the surface of carbon hollow sphere to form a zero-dimensional/three dimensional(0D/3D)Cu-doped-TiO2/C heterojunction.The optimal Cu-doped-TiO_(2)/C heterojunction demon-strated greatly enhanced photocatalytic H_(2) generation activity(14.4 mmol·g^(-1)·h^(-1))compared with TiO_(2)(0.33 mmol·g^(-1)·h^(-1))and TiO_(2)/C(0.7 mmol·g^(-1)·h^(-1)).The performance improvement was mainly due to the syner-gistic effect of carbon hollow sphere cocatalyst and Cu-doping,the Cu-doping in TiO_(2)nanoparticles can minimize charge recombination and enhance the available photoex-cited electrons,while the 3D carbon hollow spheres can act as electron traps to accelerate the charge separation and offer abundant active sites for solar water splitting reaction.
基金supported by the National Basic Research Program of China (Grant No. 2012CB932702)the National High Technology Research and Development Program of China (Grant No. 2013AA031601)+2 种基金the National Natural Science Foundation of China (Grant Nos. 50831002,51071022,11174031,and 51271020)PCSIRT,Beijing Nova Program (Grant No. 2011031)the Fundamental Research Funds for the Central Universities
文摘Zn0.99Cu0.01O films were studied experimentally and theoretically. The films were prepared by pulsed-laser deposition on Pt（111）/Ti/SiO2/Si substrates under various oxygen pressures to investigate the growth-dependence of the ferromagnetic properties. The structural, magnetic, and optical properties were studied, and it was found that all the samples possess a typical wurtzite structure, and that the films exhibit room-temperature ferromagnetism. The sample deposited at 600 ℃ and an oxygen pressure of 10 Pa showed a large saturation magnetization of 0.83 μB/Cu. The enhanced ferromagnetism in the （Cu, Li）-codoped ZnO is attributable to the existence of Zn vacancies （Vzn）, as shown by first-principles calcu- lations. The photoluminescence analysis demonstrated the existence of Vzn in both Zn0.99Cu0.01 O and （Cu, Li）-codoped ZnO thin films, and this plays an important role in the increase of ferromagnetism, according to the results of first-principles calculations.
基金supported by the National key research and development program of China (No.2016YFC04007022)the National Natural Science Foundation of China (No.21377041)the Guangdong Science and Technology Program (No.2020B121201003)。
文摘The multiple metal catalyst as a promising nanomaterial has shown excellent activity in the peroxymonosulfate(PMS)activation for pollutant degradation.However,the role of special sites and in-depth understanding of the PMS activation mechanism are not fully studied.In this study,a Cu-doped CoFe_(2)O_(4)nanocatalyst(0.5CCF)was synthesized by a sol-gel and calcination method,and used for PMS activation to remove Rhodamine B(RhB).The results showed that the Cu doping obviously enhanced the catalytic performance of CoFe_(2)O_(4),with 99.70%of RhB removed by 0.5CCF while 74.91%in the CoFe_(2)O_(4)within 15 min.Based on the X-ray photoelectron spectroscopy and electrochemical analysis,this could be ascribed to the more low valence of Co and Fe species generated on the 0.5CCF and faster electron transfers occurred in the 0.5CCF due to the Cu doping.In addition,Cu doping could provide more reaction sites for the 0.5CCF to activate PMS for RhB removal.The metal species and the surface hydroxyl were the reaction sites of PMS activation,and the surface hydroxyl played an important role in surface-bound reactive species generation.During the PMS activation,the Cu not only activated PMS to produce reactive oxygen species(ROS),but also regenerated Co^(2+)and Fe^(2+)to accelerate the PMS activation.The non-radical of ^(1)O_(2)was the main ROS with a 99.35%of contribution rate,and the SO_(5)^(·–)self-reaction was its major source.This study provides a new insight to enhance the PMS activation performance of multiple metal catalysts by Cu doping in wastewater treatment.
基金financially supported by the Henan University of Science and Technology through a grant of Postgraduate Innovation Fund(No.CXJJ-Z015)the Foundation and Advanced Technology Fund of Henan Science and Technology Department(No.11230041002)the Program for Changjiang Scholars and Innovative Research Team in University(No.IRT1234)
文摘The synthesis of Cu-doped ZnO nanosheets at room temperature was reported in our previous paper. The effects of annealing temperature on Cu-doped ZnO nanosheets were studied in this paper. Cu-doped ZnO nanosheets were annealed at 200-500℃ in air. The annealed specimens were characterized by scanning electron microscopy （SEM）, X-ray diffraction （XRD） and transmission electron microscopy （TEM）. The results show that Cu concentration in Cu-doped ZnO nanosheets reduced with increasing annealing temperature. When annealing temperature was lower than Zn melting point （410℃）, the morphologies of the Cu-doped ZnO nanosheets remained nearly the same as that before annealing. However, when the annealing temperature was over Zn melting point, Cu-doped ZnO nanosheets changed to nanowires, wormlike nanosheets or did not change. The change of Cu concentration in Cu-doped ZnO nanosheets is explained by oxidation thermodynamics. A physical model is suggested to explain the morphology changes of Cu-doped ZnO nanosheets, based on the existence of Cu-rich layer beneath Cu-doped ZnO nanosheets.
基金supported by the National Natural Science Foundation of China(Grant Nos.51272224 and 11164031)
文摘Copper （Cu）-doped ZrO2 （CZO） films with different Cu content （0 at.%- 8.07 at.%） are successfully deposited on Si （100） substrates by direct current （DC） and radio frequency （RF） magnetron co-sputtering. The influences of Cu content on structural, morphological, optical and electrical properties of CZO films are discussed in detail. The CZO films exhibit ZrO2 monocline （1^-11） preferred orientation, which indicates that Cu atoms are doped in ZrO2 host lattice. The crystallite size estimated form x-ray diffraction （XRD） increases by Cu doping, which accords with the result observed from the scanning electron microscope （SEM）. The electrical resistivity decreases from 2.63 Ω·cm to 1.48 Ω·cm with Cu doping content increasing, which indicates that the conductivity of CZO film is improved. However, the visible light transmittances decrease slightly by Cu doping and the optical band gap values decrease from 4.64 eV to 4.48 eV for CZO fihns.
基金Supported by the National Basic Research Program of China (973 Program) (2007CB924902)the National Natural Science Foundation of China (10775053, 61076089)the "Shu Guang" Project of Shanghai Education Development Foundation (09SG24)
文摘Hole carrier mediated magnetization in Cu-doped GaN is investigated by using the first-principles calculations. By studying the sp-d interaction and the direct exchange interaction among the dopants, we obtain an equation to determine the spontaneous magnetization as a function of the Cu dopant concentration and the hole carrier density. It is demonstrated that nonmagnetic Cu doped GaN can be of room-temperature ferromagnetism. The system＇s Curie temperature Tc can reach about 345 K with Cu concentration of 1.0% and hole carrier density of 5.0×10^19 cm-3. The results are in good agreement with experimental observations and indicate that ferromagnetism in this systems is tunable by controlling the Cu concentration and the hole carrier density.
基金supported by National Natural Science Foundation of China(Nos.21173028,11505019)the Science and Technology Research Project of Liaoning Provincial Education Department(No.L2013464)+2 种基金the Scientific Research Foundation for the Doctor of Liaoning Province(No.20131004)the Program for Liaoning Excellent Talents in University(No.LR2012042)Dalian Jinzhou New District Science and Technology Plan Project(No.KJCX-ZTPY-2014-0001)
文摘An atmospheric-pressure dielectric barrier discharge （DBD） gas-liquid cold plasma was employed to synthesize Cu-doped TiO~ nanoparticles in an aqueous solution with the assistance of [C2MIM]BF4 ionic liquid （IL） and using air as the working gas. The influences of the discharge voltage, IL and the amount of copper nitrite were investigated. X-ray diffraction, N2 adsorption-desorption measurements and UV-Vis spectroscopy were adopted to characterize the samples. The results showed that the specific surface area of TiO2 was promoted with Cu-doping （from 57.6 m^2.g^-1 to 106.2 m^2.g^-1 with 3% Cu-doping）, and the content of anatase was increased. Besides, the band gap energy of TiO~ with Cu-doping decreased according to the UV-Vis spec- troscopy test. The 3%Cu-IL-TiO2 samples showed the highest eificiency in degrading methylene blue （MB） dye solutions under simulated sunlight with an apparent rate constant of 0.0223 min-1, which was 1.2 times higher than that of non-doped samples. According to the characterization results, the reasons for the high photocatalytic activity were discussed.
文摘In this paper, photorefractive crystals of Cu-doped (K0.5Na0.5)0.2 (Sr0.75Ba0.25)0.9Nb2O6 (KNSBN) are systematically studied. A series of Cu-doped KNSBN crystals have been grown and the samples with Cu-dopant in different levels and thicknesses have been fabricated. Their photorefractive properties including two-wave coupling gain coefficients and response rate are experimentally studied in details. The results show that (1) with high Cudopant cocentration, the crystal has larger coupling gain coefficient, higher effective charge carrier density, and faster time response; (2) thinner sample shows larger coupling gain coefficientl (3) at shorter wavelength 9 the crystal sample shows larger coupling gain coefficient and faster time response. The Cu-doping mechanisms were briefly referred. The analyses of the relationships among the crystal’s two-wave coupling, absorption property and the self-pumped phase conjugation are given. All the results show that Cu-doped KNSBN crystals are a kind of very promising photorefractive materials.
基金Project supported by the Universiti Teknologi Malaysia(UTM)(Grant No.R.J1300000.7809.4F626)RMC for postdoctoral grants
文摘Zn（1-x）Cux O（x=0.00, 0.01, 0.03, and 0.05） nanoparticles are synthesized via the sol-gel technique using gelatin and nitrate precursors. The impact of copper concentration on the structural, optical, and antibacterial properties of these nanoparticles is demonstrated. Powder x-ray diffraction investigations have illustrated the organized Cu doping into ZnO nanoparticles up to Cu concentration of 5%（x = 0.05）. However, the peak corresponding to CuO for x= 0.01 is not distinguishable. The images of field emission scanning electron microscopy demonstrate the existence of a nearly spherical shape with a size in the range of 30–52 nm. Doping Cu creates the Cu–O–Zn on the surface and results in a decrease in the crystallite size. Photoluminescence and absorption spectra display that doping Cu causes an increment in the energy band gap. The antibacterial activities of the nanoparticles are examined against Escherichia coli（Gram negative bacteria）cultures using optical density at 600 nm and a comparison of the size of inhibition zone diameter. It is found that both pure and doped ZnO nanoparticles indicate appropriate antibacterial activity which rises with Cu doping.
文摘Porous Cu-doped SnO<sub>2</sub> thin films were synthesized by the sol-gel dip-coating method for enhancing methanol sensing performance. The effect of Cu doping concentration on the SnO<sub>2</sub> sensibility was investigated. XRD data confirm that the fabricated SnO<sub>2</sub> films are polycrystalline with tetragonal rutile crystal structure. AFM and SEM micrographs confirmed the roughness and the porosity of SnO<sub>2</sub> surface, respectively. UV-Vis spectrum shows that SnO<sub>2</sub> thin films exhibit high transmittance in the visible region ~95%. The band gap (3.80 - 3.92 eV) and the optical thickness (893 - 131 nm) of prepared films were calculated from transmittance data. The sensing results demonstrate that SnO<sub>2</sub> films have a high sensitivity and a fast response to methanol. In particular, 3% Cu-SnO<sub>2</sub> films have a higher sensitivity (98%), faster response (10-<sup>2</sup> s) and shorter recovery time (18 s) than other films.
基金supported by the National Natural Science Foundation of China(Nos.62374035,92263106,12061131009)the Science and Technology Commission of Shanghai Municipality(No.21520712600).
文摘Silver nanowires(Ag NWs)have promising application potential in electronic displays because of their superior flexibility and transparency.Doping Ni in Ag NWs has proven to be an effective strategy to im-prove its work function.However,AgNi NWs-based electrodes suffer from poor electrical conductivity under air exposure due to the low-conductivity NiO generated on its surface.Here,Cu was further doped in AgNi NWs to form AgNiCu NWs and regulate its surface oxide under long-term air exposure.Finally,it is demonstrated that the conductivity of AgNiCu NWs can acquire an improved tolerable tempera-ture(over 240℃)and prolonged high-temperature tolerance time(over 150 min)by finely regulating the doping content Cu,indicating an enhanced air-stable conductivity.The optimized AgNiCu NWs also achieve superior transparent conductivity as pure Ag NWs and high work function as AgNi NWs,which has been successfully applied in constructing an n-type photodiode with an effective rectification effect.
基金supported by the National Key Research and Development Program of China(2021YFB4001400)the Cooperation Project of Shan-dong Energy Group Co.,Ltd.(20200871)supported by 111 Project 2.0(BP0618008).
文摘This study addresses the challenge of high sintering temperatures in proton-conducting fuel cells(PCFCs)with BaCeO_(3)-doped electrolytes.We demonstrate that 1 mol%copper(Cu)doping at the B-site of BaCe_(0.7)Zr_(0.1)(Dy_(0.1)|Yb_(0.1))_(0.2)O_(3-δ)(BCZDYb)improves sintering behavior,enabling densification at1400℃.However,Cu doping disrupts stoichiometry,creating barium vacancies and reducing protonaccepting cations,affecting overall conductivity.This mechanism is confirmed through density functional theory(DFT)calculations and various experimental techniques,including crystal structure analysis using X-ray diffraction(XRD)and morphology and elemental analysis via field emission scanning electron microscopy(FESEM)and energy-dispersive X-ray spectroscopy(EDS).Electrochemical measurements are performed using the electrochemical impedance spectroscopy(EIS).The ionic conductivity of1 mol%Cu-doped BCZDYb(BCZDYb-1)is 1.49×10^(-2)S cm^(-1)at 650℃,which is~3.58 times higher than that of BCZDYb sintered at 1200℃.The BCZDYb-1 exhibits~16 times higher grain boundary conductivity when sintered at 1400℃,compared to undoped BCZDYb.The single cell employing BCZDYb-1 as the electrolyte achieved a power density of~606 mW cm^(-2)at 550℃.These results indicate that a controlled amount of Cu doping can enhance densification while maintaining high ionic co nductivity,making it suitable for practical applications in PCFCs operating at lower temperatures.
基金the Council of the President of the Russian Federation(scholarship no.СП-1413.2019.1)for supporting the studies devoted to design of new nickelate materials。
文摘The Ln_(2)NiO_(4+δ)-based layered phases have attracted much attention as components for high-performance protonic ceramic fuel cells(PCFCs)and electrolysis cells(PCECs)enabling energy conversion with good efficiency and low pollution.The present paper aims at rationally engineering the Cu-doped Pr_(2)NiO_(4+δ)materials and analysing their electrode behaviour for reversible protonic ceramic cells operating in both PCFC and PCEC modes.Complex oxides of Pr_(2)Ni_(1-x)CuxO_(4+δ)(x=0,0.1,0.2 and 0.3)were synthesised using the citrate-nitrate method.The obtained materials were characterised considering their crystalline structures,as well as thermal,thermomechanical and electrotransport properties.A special interest was focused on the quality of an electrode/electrolyte interface governing the electrochemical performance of the cells fabricated.It is shown that a copper doping of x=0.2 has a positive impact on the thermomechanical compatibility of the Ba(Ce,Zr)O_(3)-based electrolytes,providing a better adhesion to these electrolytes at low-temperature sintering and resulting in a decrease of the polarisation resistance of the air electrodes.A reversible protonic ceramic cell demonstrates a power density of~340 m W cm^(-2) and a hydrogen output flux of~3.8 ml cm^(-2) min^(-1) at 750℃.The presented results propose modernised alkaline-earth-element-free and cobalt-free electrodes that can be successfully used in the electrochemical cells based on the-state-of-the-art proton-conducting electrolytes.
基金Funded by the Natural Science Foundation of Fujian Province(No.2011J01014)the National Natural Science Foundation of China(No.11074099)
文摘The Zn1-xCuxO polycrystalline materials were prepared by doping CuO into wurtzite ZnO through solid state reaction. The high concentration of copper doping in ZnO exhibited remarkable room temperature ferromagnetism. The Experiments showed that the magnetization saturation rose with the increase of Cu content. For the low Cu content sample, the hysteresis loop was slightly tilted which indicated that the diamagnetism coexisted in this sample. The temperature dependence of magnetization of Zn1-xCuxO revealed that the magnetic exchange coupling depended on the doping concentration of Cu and there were many different local environments for magnetism. The measured hysteresis loop and temperature dependence of magnetization were overall performance of the magnetism coming from a wide distribution of ferromagnetic exchange couplings.
基金supported by the National Natu-ral Science Foundation Joint Fund(No.U1806223)the National Natural Science Foundation of China(Nos.51572249,42076039)+1 种基金the Foundation of Key Laboratory of National Defense Science and Technology(No.JS220406)the Natural Science Foundation of Shandong Province(No.ZR2020ME016).
文摘Photo-induced self-healing composites have attracted more and more attention as a kind of materials that can be controlled remotely and accurately in real time.Here,we report a strategy of a photo-responsive system based on hydrogen and ion bonds capable of performing self-healing process by ultraviolet wave-lengths,which is covalently cross-linked zinc-dimethylglyoxime-polyurethane coordination network with triple dynamic bonds.The recombination of hydrogen bond and metal coordination bond produces ef-fective healing performance.The self-healing behavior and temperature dependence of 3D micro-crack is investigated by molecular dynamics simulations to reveal the mechanism of self-healing at molecu-lar level.Moreover,the hybrid of copper-doped zinc oxide not only provides metal coordination bonds to enhance the self-healing rate,but also enhances the photothermal effect and anti-bacterial properties of polyurethane.Importantly,doping of copper generates more defects and forms a space charge layer on the surface of zinc oxide.The defects could trap surface electrons and holes,preventing the recom-bination of photo-induced electron-hole pairs,generating more heat through lattice vibration.Therefore,under ultraviolet light irradiation,the polyurethane can reach 62.7°C for 60 s,and the scratches of the polyurethane can be healed within 30 min and fully healed within 1 h.
基金Funded by the National Natural Science Foundation of China(No.11304045)the Guangdong Province National Natural Science Foundation of China(No.S2012010009955)the Science and Technology Program of Guangzhou City of China(No.2013j4100011)
文摘The nano-nickel hydroxide samples were prepared by means of ultrasonic-assisted precipitation and the impact of source/doping element/buffer on the structure of Ni（OH）： was studied. The results of XRD, IR and TEM testing clearly revealed that larger anionic radius of the nickel sources or the buffer solution was conducive to the formation of α-Ni（OH）2. The proportion of α-Ni（OH）： samples doped with two elements was larger than that doped with single element. Additionally, speciation, valence as well as the radius of doping ions can directly affect the phase of Ni（OH）2.
基金Project supported by the National High Technology Research and Development Program of China (Grant No. 2009AA03Z405)the National Natural Science Foundation of China (Grant Nos. 60908028 and 60971068)the Chinese Universities Scientific Fund (Grant No. BUPT2009RC0412)
文摘We perform a first-principles simulation to study the electronic and optical properties of wurtzite Zn1-xCuxO. The simulations are based upon the Perdew-Burke-Ernzerhof form of generalised gradient approximation within the density functional theory. Calculations are carried out in different concentrations. With increasing Cu concentration, the band gap of Znl-xCuxO decreases due to the shift of valence band. The imaginary part of the dielectric function indicates that the optical transition between O2p states in the highest valence band and Zn 4s states in the lowest conduction band shifts to the low energy range as the Cu concentration increases. Besides, it is shown that the insertion of Cu atom leads to redshift of the optical absorption edge. Meanwhile, the optical constants of pure ZnO and Zn0.75Cu0.250, such as loss function, refractive index and reflectivity, are discussed.
