The outstanding performance of O3-type NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2)(NFM111)at both high and low temperatures coupled with its impressive specific capacity makes it an excellent cathode material for sodium-ion batte...The outstanding performance of O3-type NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2)(NFM111)at both high and low temperatures coupled with its impressive specific capacity makes it an excellent cathode material for sodium-ion batteries.However,its poor cycling,owing to highpressure phase transitions,is one of its disadvantages.In this study,Cu/Ti was introduced into NFM111 cathode material using a solidphase method.Through both theoretically and experimentally,this study found that Cu doping provides a higher redox potential in NFM111,improving its reversible capacity and charge compensation process.The introduction of Ti would enhance the cycling stability of the material,smooth its charge and discharge curves,and suppress its high-voltage phase transitions.Accordingly,the NaNi_(0.27)Fe_(0.28)Mn_(0.33)Cu_(0.05)Ti_(0.06)O_(2)sample used in the study exhibited a remarkable rate performance of 142.97 mAh·g^(-1)at 0.1 C(2.0-4.2 V)and an excellent capacity retention of 72.81%after 300 cycles at 1C(1C=150 mA·g^(-1)).展开更多
We investigate the interplay between the pseudogap state and d-wave superconductivity in the two-dimensional doped Hubbard model by employing an eight-site cluster dynamical mean-field theory method.By tuning electron...We investigate the interplay between the pseudogap state and d-wave superconductivity in the two-dimensional doped Hubbard model by employing an eight-site cluster dynamical mean-field theory method.By tuning electron hopping parameters,the strong-coupling pseudogap in the two-dimensional Hubbard model can be either enhanced or suppressed in the doped Mott insulator regime.We find that in underdoped cases,the closing of pseudogap leads to a significant enhancement of superconductivity,indicating competition between the two in the underdoped regime.In contrast,at large dopings,suppressing the pseudogap is accompanied by a concurrent decrease in the superconducting transition temperature Tc,which can be attributed to a reduction in antiferromagnetic correlations behind both the pseudogap and superconductivity.We elucidate this evolving relationship between pseudogap and superconductivity across different doping regimes.展开更多
By doping with Mg atoms,the bandgap of Mg-doped NiO thin films can be adjusted larger.By using NiO and MgO as sputtering targets,Mg-doped NiO thin films were deposited using radio-frequency magnetron co-sputtering met...By doping with Mg atoms,the bandgap of Mg-doped NiO thin films can be adjusted larger.By using NiO and MgO as sputtering targets,Mg-doped NiO thin films were deposited using radio-frequency magnetron co-sputtering method in pure argon and pure oxygen gas,respectively.The crystal structure,morphological characteristics,composition and optical properties of the obtained films were compared by X-ray diffraction(XRD),scanning electron microscope(SEM),energy dispersive spectrometer(EDS)and ultraviolet(UV)-visible spectrophotometer.The properties of the thin films deposited in different sputtering gases are quite different.For the films deposited in pure argon gas,it is a polycrystalline thin film with(200)preferred orientation,while the film deposited in pure oxygen has no preferred orientation.The grain size,molar ratio of Mg to Ni atoms and optical bandgap are larger for the films deposited in pure argon gas than those deposited in oxygen gas.展开更多
In this paper, we have demonstrated an Er-doped ultrafast laser with a single mode fiber-gradient index multimode fiber-single mode fiber(SMF-GIMF-SMF, SMS) structure as saturable absorber(SA), which can generate not ...In this paper, we have demonstrated an Er-doped ultrafast laser with a single mode fiber-gradient index multimode fiber-single mode fiber(SMF-GIMF-SMF, SMS) structure as saturable absorber(SA), which can generate not only stable single-pulse state, but also special mode-locked pulses with the characteristics of high energy and noisy behaviors at proper pump power and cavity polarization state. In addition, we have deeply investigated the real-time spectral evolutions of the mode-locked pulses through the dispersive Fourier transformation(DFT) technique. It can be found that the pulse regime can actually consist of a lot of small noise pulses with randomly varying intensities. We believe that these results will further enrich the nonlinear dynamical processes in the ultrafast lasers.展开更多
We used the natural product chamomile as a carbon source to synthesize praseodymium(Pr) and nitrogen(N) co-doped biomass carbon dots(Pr/N-BCDs) with remarkable luminescence properties by one-step hydrothermal method.C...We used the natural product chamomile as a carbon source to synthesize praseodymium(Pr) and nitrogen(N) co-doped biomass carbon dots(Pr/N-BCDs) with remarkable luminescence properties by one-step hydrothermal method.Compared with single N-doped BCDs(N-BCDs) and Pr-doped BCDs(Pr-BCDs),Pr/N-BCDs not only showed better fluorescence properties and stability but also achieved a significant increase in quantum yield of 12%.More importantly,under certain conditions,Pr/N-BCDs and 2,4-dinitrophenylhydrazide(2,4-DNPH) had significant fluorescence internal filtration effect(IFE) and dynamic quenching effect,and in the concentration range of0.50-20 μmol·L^(-1),the concentration of 2,4-DNPH had a good linear relationship with the fluorescence quenching signal,and the detection limit was as low as 2.1 nmol·L^(-1).展开更多
N-doped graphite carbon sphere coated cobalt nanoparticle catalyst(Co@C-N-900),prepared by solvothermal-calcination method,is applied to activate peroxymonosulfate(PMS)for bisphenol A(BPA)elimination.The outcomes demo...N-doped graphite carbon sphere coated cobalt nanoparticle catalyst(Co@C-N-900),prepared by solvothermal-calcination method,is applied to activate peroxymonosulfate(PMS)for bisphenol A(BPA)elimination.The outcomes demonstrate that the Co@C-N-900 could effectively activate PMS,thereby causing efficient removal of BPA in water.In addition,the Co@C-N-900/PMS system also has the advantages of low metal leaching,applicability in high salinity environments,good selectivity and stability.Further investigations using electron paramagnetic resonance,chronoamperometry,and quenching experiments demonstrated that the Co@C-N-900/PMS system is a typical non-radical route with singlet oxygen(^(1)O_(2))as the main reactive oxygen species(ROS).Density functional theory calculations(DFT)indicate that N-doping can effectively regulate the charge distribution on the catalyst surface,generating acidic/alkaline sites favorable for PMS adsorption and activation.Furthermore,it also can enhance the interaction and charge transfer capacity between the Co@C-N-900 and PMS.Lastly,LC-QTOF-MS/MS analysis revealed two possible BPA degradation pathways:(1)^(1)O_(2)attacked the isopropyl group in BPA between the two phenyl groups,causingβ-scission to occur.(2)Following the oxidation of the hydroxyl group in the aromatic ring of BPA,^(1)O_(2)could cause furtherβ-scission.The prepared Co@C-N-900 catalyst is a very promising catalyst,which would offer a workable remedy for treating water pollution.展开更多
The objective of this study was to identify and synthesize functional groups for the efficient adsorption of volatile organic compounds(VOCs)through a combination of theoretical calculations,molecular design,and exper...The objective of this study was to identify and synthesize functional groups for the efficient adsorption of volatile organic compounds(VOCs)through a combination of theoretical calculations,molecular design,and experimental validation.The density functional theory(DFT)calculation,focusing on the P-containing functional groups,showed that methanol adsorption was dominated by the electrostatic interaction between the carbon surface and methanol,while toluene was mainly trapped through π-π dispersive interaction between toluene molecule and functional group structure.The experimental results showed the phosphorus-doped carbon materials(PCAC)prepared by directly activating potassium phytate had a phosphorus content of up to 4.5%(atom),mainly in the form of C-O-P(O)(OH)_(2).The material exhibited a high specific area(987.6m^(2)·g^(-1))and a large adsorption capacity for methanol(440.0 mg·g^(-1))and toluene(350.1 mg·g^(-1)).These properties were superior to those of the specific commercial activated carbon(CAC)sample used for comparison in this study.The adsorption efficiencies per unit specific surface area of PCAC were 0.45 mg·g^(-1) m^(-2) for methanol and 0.35 mg·g^(-1)·m^(-2) for toluene.This study provided a novel theoretical and experimental framework for the molecular design of polarized elements to enhance the adsorption of polar gases,offering significant advancements over existing commercial solutions.展开更多
Luminescent materials for application in temperature sensing have caught a lot of interest in recent years.Particularly erbium(Er^(3+))-doped fluoride-based materials(EFM),which are readily accessible by near-infrared...Luminescent materials for application in temperature sensing have caught a lot of interest in recent years.Particularly erbium(Er^(3+))-doped fluoride-based materials(EFM),which are readily accessible by near-infrared(NIR)excitation to produce efficient photon conversion.It has been established that ytterbium(Yb^(3+))may improve the performance of EFMs in both bulk and nanostructured forms by energy transfer channels among rare-earth ions in interstitial clusters.In this work,a comprehensive analysis of the Er^(3+):Yb^(3+):CaF_(2)crystalline structure,photoluminescence,and energy transfer from Yb^(3+)to Er^(3+)is presented for powders prepared by combustion synthesis.The Er^(3+):Yb^(3+):CaF_(2)powders display exceptional photon down-shift and up-conversion when exposed to NIR light(λ=975 nm).The luminescence spectral change of the NIR emission around 1.5μm,which corresponds to the Er^(3+)electronic transition ^(4)I_(13/2)→^(4)I_(15/2),was investigated in a temperature range of 298-423 K for application in temperature sensing of biological systems exploring the third biological window.The luminescence intensity ratio technique was applied to the thermally coupled Stark sublevels of states^(4)I_(13/2)and^(4)I_(15/2)with the highest estimated temperature relative sensitivity being around 0.4%/K at 298 K.展开更多
Tin-based metal organic complexes with breakable coordination bonds,multiple active sites,and high theoretical capacity have attracted wide attentiorials for lithium-ion batteries(LIBs).However,the inferior electrical...Tin-based metal organic complexes with breakable coordination bonds,multiple active sites,and high theoretical capacity have attracted wide attentiorials for lithium-ion batteries(LIBs).However,the inferior electrical conductivity and significant volume changes have limited their electrochemical stability and practical application performance.This work proposes a universal doping strategy for the preparation of tin-phthalic acid complexes(Sn-MOF)doped with metal atoms(Al,Cr,Mn,Fe,Co,Ni,Cu,Zn).Metal atoms are uniformly dispersed within Sn-MOF for enhancing electrical conductivity and accommodating appropriate volume expansion,resulting in improved rate capability and cycling stability.Additionally,compared to a series of doped Sn-MOF,Zn-doped Sn-MOF exhibits the most exceptional electrochemical performance with a high reversible capacity of 1131 mAh·g^(-1)and stable cycling performance at a current density of 0.5 A·g^(-1),delivering a capacity of 1065 mAh·g^(-1)after 500 cycles.Zn-doping catalyzes the lithiation reaction between Sn-MOF and Li^(+),promoting their reaction kinetics during the first cycle.Furthermore,the Zn-doped Sn-MOF is inclined to form a thin and stable solid electrolyte interface film to maintain cyclic stability.展开更多
Proton ceramic fuel cell efficiently converts chemical energy into electrical energy,representing a pivotal component of future energy systems.However,its current performance is hindered by limitations in cathode and ...Proton ceramic fuel cell efficiently converts chemical energy into electrical energy,representing a pivotal component of future energy systems.However,its current performance is hindered by limitations in cathode and electrolyte materials,thereby impeding commercialization.Anion doping emerges as a promising strategy to enhance the electrochemical efficiency of perovskite-based cathodes and electrolytes.However,integrating this approach within a single-cell structure still requires further research.In this study,F-doped perovskite oxides BaCo_(0.4)Fe_(0.4)Zr_(0.1)Y_(0.1)O_(2.9-δ)F_(0.1)(BCFZYF)and BaZr_(0.1)Ce_(0.7)Y_(0.1)Yb_(0.1)O_(2.9-δ)F_(0.1)(BZCYYbF)were synthesized for use as the cathode and electrolyte,respectively,in proton ceramic fuel cells.Our findings demonstrate that F-doped perovskite oxides exhibit superior electrochemical performance and enhanced structural stability.Furthermore,doping both electrodes and electrolytes with F ions improves their interfacial compatibility.The cell configuration BCFZYF|BZCYYbF|Ni-BZCYYbF achieved a peak power density of 998 mW·cm^(−2)at 650℃using H_(2)as fuel,and it maintained stable operation for over 400 h at 550℃with a current density of 400 mA·cm^(−2).This research underscores an effective strategy for enhancing the performance and durability of proton ceramic fuel cells.展开更多
Rational tuning of crystallographic surface and metal doping were effective to enhance the catalytic performance of metal organic frameworks,but limited work has been explored for achieving modulation of crystal facet...Rational tuning of crystallographic surface and metal doping were effective to enhance the catalytic performance of metal organic frameworks,but limited work has been explored for achieving modulation of crystal facets and metal doping in a single system.MIL-68(In)was promising for photocatalytic applications due to its low toxicity and excellent photoresponsivity.However,its catalytic activity was constrained by severe carrier recombination and a lack of active sites.Herein,increased(001)facet ratio and active sites exposure were simultaneously realized by cobalt doping in MIL-68(In)through a one-pot solvothermal strategy.Optimized MIL-68(In/Co)-2.5 exhibited remarkable catalytic performance in comparison with pristine MIL-68(In)and other MIL-68(In/Co).The reaction kinetic constant and degradation efficiency of MIL-68(In/Co)were approximately twice and 17%higher than the pristine MIL-68(In)in 36 min reaction,respectively.Density functional theory calculations revealed that Co dopant could modulate the orientation of MIL-68(In)facets,facilitate the exchange of electrons and reduce the adsorption energy of peroxymonosulfate(PMS).This work provides a novel pathway for improvement of In-based MOFs in PMS/vis system,it also promotes the profound comprehension of the correlation between crystal facet regulation and catalytic activation in the PMS/vis system.展开更多
The previous studies mainly focused on improving microwave absorbing(MA)performances of MA materials.Even so,these designed MA materials were very difficult to be employed in complex and changing environments owing to...The previous studies mainly focused on improving microwave absorbing(MA)performances of MA materials.Even so,these designed MA materials were very difficult to be employed in complex and changing environments owing to their single-functionalities.Herein,a combined Prussian blue analogues derived and catalytical chemical vapor deposition strategy was proposed to produce hierarchical cubic sea urchin-like yolk–shell CoNi@Ndoped carbon(NC)-CoNi@carbon nanotubes(CNTs)mixed-dimensional multicomponent nanocomposites(MCNCs),which were composed of zerodimensional CoNi nanoparticles,three-dimensional NC nanocubes and onedimensional CNTs.Because of good impedance matching and attenuation characteristics,the designed CoNi@NC-CoNi@CNTs mixed-dimensional MCNCs exhibited excellent MA performances,which achieved a minimum reflection loss(RL_(min))of−71.70 dB at 2.78 mm and Radar Cross section value of−53.23 dB m^(2).More importantly,the acquired results demonstrated that CoNi@NC-CoNi@CNTs MCNCs presented excellent photothermal,antimicrobial and anti-corrosion properties owing to their hierarchical cubic sea urchin-like yolk–shell structure,highlighting their potential multifunctional applications.It could be seen that this finding not only presented a generalizable route to produce hierarchical cubic sea urchin-like yolk–shell magnetic NC-CNTs-based mixed-dimensional MCNCs,but also provided an effective strategy to develop multifunctional MCNCs and improve their environmental adaptabilities.展开更多
Foreword It is our great privilege,as vip Editors of the International Journal of Minerals,Metallurgy and Materials(IJMMM),to present this special issue on“High-Entropy and Multicomponent-Doped Materials for Energy...Foreword It is our great privilege,as vip Editors of the International Journal of Minerals,Metallurgy and Materials(IJMMM),to present this special issue on“High-Entropy and Multicomponent-Doped Materials for Energy Applications:Innovations in Energy Conversion and Storage.”This collection highlights the latest research developments in the preparation,optimizing properties,and exploring potential applications of high-entropy materials(HEMs)and other com-pounds with increased configurational entropy.展开更多
Miniaturized erbium-doped waveguide amplifiers attracted great interests in recent decades due to their high gain-efficiency and function-scalability in the telecom C-band.In this work,an erbium-doped thin film lithiu...Miniaturized erbium-doped waveguide amplifiers attracted great interests in recent decades due to their high gain-efficiency and function-scalability in the telecom C-band.In this work,an erbium-doped thin film lithium niobate waveguide amplifier achieving>10 dB off-chip(fiber-to-fiber)net gain and>20 mW fiber-output amplified power is demonstrated,thanks to the low-propagation-loss waveguides and robust waveguide edge-couplers prepared by the photolithography assisted chemomechanical etching technique.Systematic investigation on the fabricated waveguide amplifiers reveals remarkable optical gain around the peak wavelength of 1532 nm as well as the low fiber-coupling loss of-1.2 dB/facet.A fiber Bragg-grating based waveguide laser is further demonstrated using the fabricated waveguide amplifier as the external gain chip,which generates>2 mW off-chip power continuous-wave lasing around the gain peak at 1532 nm.The unambiguous demonstration of fiber-to-fiber net gain of the erbium-doped thinfilm lithium niobate(TFLN)waveguide amplifier as well as its external gain chip application will benefit diverse fields demanding scalable gain elements with highspeed tunability.展开更多
Electrocatalytic conversion of renewable biomass is emerging as a promising route for sustainable chemical production;hence it urgently calls for developing efficient electrocatalysts with low potentials and high curr...Electrocatalytic conversion of renewable biomass is emerging as a promising route for sustainable chemical production;hence it urgently calls for developing efficient electrocatalysts with low potentials and high current densities.Herein,a Pr-doped Co(OH)_(2)hexagonal sheet(Pr/Co=1/9,in mole)is synthesized by electrodeposition as highly performant catalyst for 5-hydroxymethylfurfural(HMF)oxidation reaction(HMFOR)to produce 2,5-furandicarboxylic acid(FDCA).This novel and low-cost catalyst possesses a rather low onset potential of 1.05 V(vs.RHE)and requires only 1.10 V(vs.RHE)to reach a current density of 10 mA cm^(-2)for HMFOR,significantly outperforming Co(OH)_(2)benchmark(i.e.,210 mV higher to reach10 m A cm^(-2)).The origin of Pr promotion effect as well as the evolution of CoOOH catalytic sites and HMFOR process has been deeply elucidated by physical characterizations,kinetic experiments,in situ electrochemical techniques,and theoretical calculations.The unique Pr-ameliorated CoOOH active centers enable 100%conversion of HMF,99.6%selectivity of FDCA,and 99.7%Faraday efficiency,with a superior cycling durability toward HMFOR.This can be one of the most outstanding results for Co-based HMFOR catalysts to date in the literature.Thereby this work can help open up new horizons for constructing novel and efficient Co-based electrocatalysts by the utilization of lanthanide elements.展开更多
In the past century,industrial and economic growth relied heavily on fossil fuels such as coal,oil,and natural gas.As the society energy demands continue to grow,these fossil fuel reserves are depleted,leading to sign...In the past century,industrial and economic growth relied heavily on fossil fuels such as coal,oil,and natural gas.As the society energy demands continue to grow,these fossil fuel reserves are depleted,leading to significant environmental issues[1].Currently,sustainable biomass resources have attracted much attention as potential substitutes to fossil fuels for producing biofuels and commodity chemicals[2].展开更多
Mn^(2+)-doped CsPbCl_(3)(Mn^(2+):CsPbCl_(3)) nanocrystals(NCs) have attracted considerable attention due to their unique strong and broad orange-red emission band,presenting promising applications in the field of phot...Mn^(2+)-doped CsPbCl_(3)(Mn^(2+):CsPbCl_(3)) nanocrystals(NCs) have attracted considerable attention due to their unique strong and broad orange-red emission band,presenting promising applications in the field of photoelectric devices.However,pristine Mn^(2+):CsPbCl_(3)NCs commonly suffer from low photoluminescence quantum yield(PL QY) and stability issues.Herein,we introduced europium ions(Eu^(3+))into Mn^(2+):CsPbCl_(3)NCs via the thermal injection synthesis method to obtain high performance Eu^(3+)and Mn^(2+)codoped CsPbCl_(3)(Eu^(3+)/Mn^(2+):CsPbCl_(3)) NCs.The maximum PL QY of the resulting Eu^(3+)/Mn^(2+):CsPbCl_(3)NCs reaches up to 90.92%.It is found that the doping of Eu^(3+)ions significantly reduces the non-radiative recombination caused by high defect states,and improves the energy transfer efficiency from exciton to Mn^(2+),thereby boosting the PL performance.Moreover,doping Eu^(3+)ions notably improves the UV-light and water stability of Mn^(2+):CsPbCl_(3)NCs.We further demonstrate the application versatility of Eu^(3+)/Mn^(2+):CsPbCl_(3)NCs in white light emitting diodes(WLEDs) and optical anticounterfeiting applications.This work provides a valuable perspective for the attainment of high performance Mn^(2+):CsPbCl_(3)NCs and lays a foundation for the codoping of other lanthanide ions to adjust the luminescence properties of Mn^(2+):CsPbCl_(3)NCs.展开更多
In this paper,we have mainly studied the amplification effect of thulium-doped fiber amplifier(TDFA)at 2µm,and compared different amplification effects of the one-stage TDFA,two-stage TDFA and three-stage TDFA at...In this paper,we have mainly studied the amplification effect of thulium-doped fiber amplifier(TDFA)at 2µm,and compared different amplification effects of the one-stage TDFA,two-stage TDFA and three-stage TDFA at proper conditions.The simulation results show that within the effective threshold,with the increase of the pump power,the amplification effect of the optical amplifier improves,but the signal-to-noise ratio(SNR)of the output signal decreases,in order to balance the gain benefit and noise coefficient of TDFA,we can use a multi-stage amplification structure.Three-stage backward-pumped series 2.06µm TDFA,whose slope efficiency can achieve 11%at certain condition.At 5.2 W pump power,the output signal gain of 2µm TDFA exceeds 20 dB,and the output SNR is higher than 32 dB.In addition,the effect of the optimum length of thulium-doped fiber on the amplification performance of 2µm TDFA is also analyzed in this paper.These simulation results are important for the experiment and design of 2µm TDFA.展开更多
It is anticipated to remove highly hazardous tetracycline antibiotic from aqueous solution photocatalytically by using Gd doped spinal ferrite.In this work,both ZnFe_(2)O_(4)and Gd doped ZnFe_(2)O_(4)photocatalysts we...It is anticipated to remove highly hazardous tetracycline antibiotic from aqueous solution photocatalytically by using Gd doped spinal ferrite.In this work,both ZnFe_(2)O_(4)and Gd doped ZnFe_(2)O_(4)photocatalysts were hydrothermally fabricated and characterized by different techniques.The spherical photocatalysts show extended photocatalytic removal efficiency under visible light.The optimized sample(ZnFe_(1.96)Cd_(0.04)O_(4))removes 78%antibiotic in 80 min.Moreover,under simulated solar light irradiation,the rate of hydrogen produced from water splitting photocatalysis with ZnFe_(1.96)Cd_(0.04)O_(4)reaches 230.4μmol/(g h).These increased activities are attributed to the increased specific surface area,the expanded light absorption range and the enhanced charge separation realized by doping Gd.According to the charge trapping study,both superoxide(·O_(2)^(-))and hydroxyl radicals(·OH)were the major active species in the process of removing antibiotic.This research provides a feasible way to fabricate low cost photocatalysts for the eradication of highly hazardous pollutants from aqueous solution.展开更多
Based on the nonlinear saturable absorption properties(NSAPs)of a two-dimensional(2D)material of antimony selenide(Sb_(2)Se_(3)),a Q-switched erbium-doped fiber(EDF)laser is systematically demonstrated.The Sb_(2)Se_(3...Based on the nonlinear saturable absorption properties(NSAPs)of a two-dimensional(2D)material of antimony selenide(Sb_(2)Se_(3)),a Q-switched erbium-doped fiber(EDF)laser is systematically demonstrated.The Sb_(2)Se_(3)nano sheets are prepared by liquid-phase exfoliation(LPE)method.After the sandwich-structured Sb_(2)Se_(3)saturable absorber(SA)is fabricated,the NSAPs are characterized and the modulation depth,the saturation intensity and the unsaturated loss are determined to be 25.2%,2.02 MW/cm^(2),and 3.29%,respectively.When the as-prepared Sb_(2)Se_(3)-SA is integrated into the ring cavity,the laser operates at a stable Q-switching regime in the pump power range of 100—400 mW.The laser oscillates at the central wavelength of 1558.48 nm with a 3 dB bandwidth of 2.32 nm.Take the advantages of the Sb_(2)Se_(3)-SA,the pulse duration can be compressed from 40.49 kHz to 128.12 kHz.At the pump power of 400 mW,the Q-switching laser gives the narrowest pulse duration the highest average output power,the largest pulse energy,and the signal-to-noise ratio(SNR)of 0.93μs,2.16 mW,16.89 nJ,and 53 dB,respectively.Our new attempt on Sb_(2)Se_(3)-based Q-switched EDF laser,combining the existing mode-locking achievements,proves that Sb_(2)Se_(3)is a powerful candidate for pulse compression due to the characteristics of high modulation depth and high stability.展开更多
基金supported by the Low-Cost Long-Life Batteries program,China(No.WL-24-08-01)the National Natural Science Foundation of China(No.22279007)。
文摘The outstanding performance of O3-type NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2)(NFM111)at both high and low temperatures coupled with its impressive specific capacity makes it an excellent cathode material for sodium-ion batteries.However,its poor cycling,owing to highpressure phase transitions,is one of its disadvantages.In this study,Cu/Ti was introduced into NFM111 cathode material using a solidphase method.Through both theoretically and experimentally,this study found that Cu doping provides a higher redox potential in NFM111,improving its reversible capacity and charge compensation process.The introduction of Ti would enhance the cycling stability of the material,smooth its charge and discharge curves,and suppress its high-voltage phase transitions.Accordingly,the NaNi_(0.27)Fe_(0.28)Mn_(0.33)Cu_(0.05)Ti_(0.06)O_(2)sample used in the study exhibited a remarkable rate performance of 142.97 mAh·g^(-1)at 0.1 C(2.0-4.2 V)and an excellent capacity retention of 72.81%after 300 cycles at 1C(1C=150 mA·g^(-1)).
基金supported by the National Natural Science Foundation of China(Grant Nos.12274472,12494594,12494591,and 92165204)National Key Research and Development Program of China(Grant No.2022YFA1402802)+2 种基金Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices(Grant No.2022B1212010008)Guangdong Fundamental Research Center for Magnetoelectric Physics(Grant No.2024B0303390001)Guangdong Provincial Quantum Science Strategic Initiative(Grant No.GDZX2401010)。
文摘We investigate the interplay between the pseudogap state and d-wave superconductivity in the two-dimensional doped Hubbard model by employing an eight-site cluster dynamical mean-field theory method.By tuning electron hopping parameters,the strong-coupling pseudogap in the two-dimensional Hubbard model can be either enhanced or suppressed in the doped Mott insulator regime.We find that in underdoped cases,the closing of pseudogap leads to a significant enhancement of superconductivity,indicating competition between the two in the underdoped regime.In contrast,at large dopings,suppressing the pseudogap is accompanied by a concurrent decrease in the superconducting transition temperature Tc,which can be attributed to a reduction in antiferromagnetic correlations behind both the pseudogap and superconductivity.We elucidate this evolving relationship between pseudogap and superconductivity across different doping regimes.
基金supported by the Jilin Provincial Scientific and Technological Development Program(No.20220101036JC)。
文摘By doping with Mg atoms,the bandgap of Mg-doped NiO thin films can be adjusted larger.By using NiO and MgO as sputtering targets,Mg-doped NiO thin films were deposited using radio-frequency magnetron co-sputtering method in pure argon and pure oxygen gas,respectively.The crystal structure,morphological characteristics,composition and optical properties of the obtained films were compared by X-ray diffraction(XRD),scanning electron microscope(SEM),energy dispersive spectrometer(EDS)and ultraviolet(UV)-visible spectrophotometer.The properties of the thin films deposited in different sputtering gases are quite different.For the films deposited in pure argon gas,it is a polycrystalline thin film with(200)preferred orientation,while the film deposited in pure oxygen has no preferred orientation.The grain size,molar ratio of Mg to Ni atoms and optical bandgap are larger for the films deposited in pure argon gas than those deposited in oxygen gas.
基金supported by the Guangdong Basic and Applied Basic Research Foundation (No.2023A1515010093)the Shenzhen Fundamental Research Program (Stable Support Plan Program)(Nos.JCYJ20220809170611004, 20231121110828001 and 20231121113641002)the National Taipei University of Technology-Shenzhen University Joint Research Program (No.2024001)。
文摘In this paper, we have demonstrated an Er-doped ultrafast laser with a single mode fiber-gradient index multimode fiber-single mode fiber(SMF-GIMF-SMF, SMS) structure as saturable absorber(SA), which can generate not only stable single-pulse state, but also special mode-locked pulses with the characteristics of high energy and noisy behaviors at proper pump power and cavity polarization state. In addition, we have deeply investigated the real-time spectral evolutions of the mode-locked pulses through the dispersive Fourier transformation(DFT) technique. It can be found that the pulse regime can actually consist of a lot of small noise pulses with randomly varying intensities. We believe that these results will further enrich the nonlinear dynamical processes in the ultrafast lasers.
基金supported by the National Natural Science Foundation of China (Grant No.22063010)the Natural Science Foundation of Shaanxi Province (Grant No.2022QFY07-05)Yan'an Science and Technology Plan Project (Grants No.2022SLJBZ-002, 2023-CYL-193)。
文摘We used the natural product chamomile as a carbon source to synthesize praseodymium(Pr) and nitrogen(N) co-doped biomass carbon dots(Pr/N-BCDs) with remarkable luminescence properties by one-step hydrothermal method.Compared with single N-doped BCDs(N-BCDs) and Pr-doped BCDs(Pr-BCDs),Pr/N-BCDs not only showed better fluorescence properties and stability but also achieved a significant increase in quantum yield of 12%.More importantly,under certain conditions,Pr/N-BCDs and 2,4-dinitrophenylhydrazide(2,4-DNPH) had significant fluorescence internal filtration effect(IFE) and dynamic quenching effect,and in the concentration range of0.50-20 μmol·L^(-1),the concentration of 2,4-DNPH had a good linear relationship with the fluorescence quenching signal,and the detection limit was as low as 2.1 nmol·L^(-1).
基金the financial support from Sichuan Science and Technology Program(No.2023NSFSC0847)Scientific Research and Innovation Team Program of Sichuan University of Science and Technology(No.SUSE652A003)+3 种基金Talent Introduction Project of Sichuan University of Science and Engineering(No.2021RC03)Talent Introduction Project of Sichuan University of Science and Engineering(No.2021RC05)the Undergraduate Training Program for Innovation and Entrepreneurship(No.CX2024042)The Innovation Fund of Postgraduate,Sichuan University of Science&Engineering(No.Y2024094)。
文摘N-doped graphite carbon sphere coated cobalt nanoparticle catalyst(Co@C-N-900),prepared by solvothermal-calcination method,is applied to activate peroxymonosulfate(PMS)for bisphenol A(BPA)elimination.The outcomes demonstrate that the Co@C-N-900 could effectively activate PMS,thereby causing efficient removal of BPA in water.In addition,the Co@C-N-900/PMS system also has the advantages of low metal leaching,applicability in high salinity environments,good selectivity and stability.Further investigations using electron paramagnetic resonance,chronoamperometry,and quenching experiments demonstrated that the Co@C-N-900/PMS system is a typical non-radical route with singlet oxygen(^(1)O_(2))as the main reactive oxygen species(ROS).Density functional theory calculations(DFT)indicate that N-doping can effectively regulate the charge distribution on the catalyst surface,generating acidic/alkaline sites favorable for PMS adsorption and activation.Furthermore,it also can enhance the interaction and charge transfer capacity between the Co@C-N-900 and PMS.Lastly,LC-QTOF-MS/MS analysis revealed two possible BPA degradation pathways:(1)^(1)O_(2)attacked the isopropyl group in BPA between the two phenyl groups,causingβ-scission to occur.(2)Following the oxidation of the hydroxyl group in the aromatic ring of BPA,^(1)O_(2)could cause furtherβ-scission.The prepared Co@C-N-900 catalyst is a very promising catalyst,which would offer a workable remedy for treating water pollution.
基金supported by the Open Project of Xiangjiang Laboratory (22XJ03026)the National Natural Science Foundation of China (72004060)+3 种基金the Provincial Natural Science Foundation of Hunan Province (2022JJ30015)the Scientific Research Project of Hunan Education Department, China (23A0457)Environmental Protection Scientific Research Project of Hunan Province (HBKT2021021)the “Digital-intelligence+” interdisciplinary research project of Hunan University of Technology and Business (2023SZJ22)
文摘The objective of this study was to identify and synthesize functional groups for the efficient adsorption of volatile organic compounds(VOCs)through a combination of theoretical calculations,molecular design,and experimental validation.The density functional theory(DFT)calculation,focusing on the P-containing functional groups,showed that methanol adsorption was dominated by the electrostatic interaction between the carbon surface and methanol,while toluene was mainly trapped through π-π dispersive interaction between toluene molecule and functional group structure.The experimental results showed the phosphorus-doped carbon materials(PCAC)prepared by directly activating potassium phytate had a phosphorus content of up to 4.5%(atom),mainly in the form of C-O-P(O)(OH)_(2).The material exhibited a high specific area(987.6m^(2)·g^(-1))and a large adsorption capacity for methanol(440.0 mg·g^(-1))and toluene(350.1 mg·g^(-1)).These properties were superior to those of the specific commercial activated carbon(CAC)sample used for comparison in this study.The adsorption efficiencies per unit specific surface area of PCAC were 0.45 mg·g^(-1) m^(-2) for methanol and 0.35 mg·g^(-1)·m^(-2) for toluene.This study provided a novel theoretical and experimental framework for the molecular design of polarized elements to enhance the adsorption of polar gases,offering significant advancements over existing commercial solutions.
基金Project supported in part by the Brazilian Agency Conselho Nacional de Desenvolvimento Científico e Tecnológico(CNPq)。
文摘Luminescent materials for application in temperature sensing have caught a lot of interest in recent years.Particularly erbium(Er^(3+))-doped fluoride-based materials(EFM),which are readily accessible by near-infrared(NIR)excitation to produce efficient photon conversion.It has been established that ytterbium(Yb^(3+))may improve the performance of EFMs in both bulk and nanostructured forms by energy transfer channels among rare-earth ions in interstitial clusters.In this work,a comprehensive analysis of the Er^(3+):Yb^(3+):CaF_(2)crystalline structure,photoluminescence,and energy transfer from Yb^(3+)to Er^(3+)is presented for powders prepared by combustion synthesis.The Er^(3+):Yb^(3+):CaF_(2)powders display exceptional photon down-shift and up-conversion when exposed to NIR light(λ=975 nm).The luminescence spectral change of the NIR emission around 1.5μm,which corresponds to the Er^(3+)electronic transition ^(4)I_(13/2)→^(4)I_(15/2),was investigated in a temperature range of 298-423 K for application in temperature sensing of biological systems exploring the third biological window.The luminescence intensity ratio technique was applied to the thermally coupled Stark sublevels of states^(4)I_(13/2)and^(4)I_(15/2)with the highest estimated temperature relative sensitivity being around 0.4%/K at 298 K.
基金support from Natural Science Foundations of Henan Province(Nos.222300420502 and 232300420093)the Program for Science and Technology Innovation Talents in Universities of Henan Province(No.24HASTIT006)the Key Science and Technology Program of Henan Province(No.222102240044)。
文摘Tin-based metal organic complexes with breakable coordination bonds,multiple active sites,and high theoretical capacity have attracted wide attentiorials for lithium-ion batteries(LIBs).However,the inferior electrical conductivity and significant volume changes have limited their electrochemical stability and practical application performance.This work proposes a universal doping strategy for the preparation of tin-phthalic acid complexes(Sn-MOF)doped with metal atoms(Al,Cr,Mn,Fe,Co,Ni,Cu,Zn).Metal atoms are uniformly dispersed within Sn-MOF for enhancing electrical conductivity and accommodating appropriate volume expansion,resulting in improved rate capability and cycling stability.Additionally,compared to a series of doped Sn-MOF,Zn-doped Sn-MOF exhibits the most exceptional electrochemical performance with a high reversible capacity of 1131 mAh·g^(-1)and stable cycling performance at a current density of 0.5 A·g^(-1),delivering a capacity of 1065 mAh·g^(-1)after 500 cycles.Zn-doping catalyzes the lithiation reaction between Sn-MOF and Li^(+),promoting their reaction kinetics during the first cycle.Furthermore,the Zn-doped Sn-MOF is inclined to form a thin and stable solid electrolyte interface film to maintain cyclic stability.
基金supported by the National Natural Science Foundation of China(No.22278203)The authors appreciate the support of Zhejiang Zheneng Technology and Environment Group Co.,Ltd’s project(No.TD-KJ-23-005:Methanation of carbon monoxide coupled with in-situ formed hydrogen in a low-temperature SOEC reactor).
文摘Proton ceramic fuel cell efficiently converts chemical energy into electrical energy,representing a pivotal component of future energy systems.However,its current performance is hindered by limitations in cathode and electrolyte materials,thereby impeding commercialization.Anion doping emerges as a promising strategy to enhance the electrochemical efficiency of perovskite-based cathodes and electrolytes.However,integrating this approach within a single-cell structure still requires further research.In this study,F-doped perovskite oxides BaCo_(0.4)Fe_(0.4)Zr_(0.1)Y_(0.1)O_(2.9-δ)F_(0.1)(BCFZYF)and BaZr_(0.1)Ce_(0.7)Y_(0.1)Yb_(0.1)O_(2.9-δ)F_(0.1)(BZCYYbF)were synthesized for use as the cathode and electrolyte,respectively,in proton ceramic fuel cells.Our findings demonstrate that F-doped perovskite oxides exhibit superior electrochemical performance and enhanced structural stability.Furthermore,doping both electrodes and electrolytes with F ions improves their interfacial compatibility.The cell configuration BCFZYF|BZCYYbF|Ni-BZCYYbF achieved a peak power density of 998 mW·cm^(−2)at 650℃using H_(2)as fuel,and it maintained stable operation for over 400 h at 550℃with a current density of 400 mA·cm^(−2).This research underscores an effective strategy for enhancing the performance and durability of proton ceramic fuel cells.
基金supported by the National Natural Science Foundation of China(Nos.52100087,52170079,U20A20322)Science and Technology Development Program of Jilin Province,China(Nos.20220508100RC,20230402035GH).
文摘Rational tuning of crystallographic surface and metal doping were effective to enhance the catalytic performance of metal organic frameworks,but limited work has been explored for achieving modulation of crystal facets and metal doping in a single system.MIL-68(In)was promising for photocatalytic applications due to its low toxicity and excellent photoresponsivity.However,its catalytic activity was constrained by severe carrier recombination and a lack of active sites.Herein,increased(001)facet ratio and active sites exposure were simultaneously realized by cobalt doping in MIL-68(In)through a one-pot solvothermal strategy.Optimized MIL-68(In/Co)-2.5 exhibited remarkable catalytic performance in comparison with pristine MIL-68(In)and other MIL-68(In/Co).The reaction kinetic constant and degradation efficiency of MIL-68(In/Co)were approximately twice and 17%higher than the pristine MIL-68(In)in 36 min reaction,respectively.Density functional theory calculations revealed that Co dopant could modulate the orientation of MIL-68(In)facets,facilitate the exchange of electrons and reduce the adsorption energy of peroxymonosulfate(PMS).This work provides a novel pathway for improvement of In-based MOFs in PMS/vis system,it also promotes the profound comprehension of the correlation between crystal facet regulation and catalytic activation in the PMS/vis system.
基金support from the National Natural Science Foundation of China(U21A2093)Shaanxi Province Key Research and Development Plan Project(2023-YBGY-461)+4 种基金Platform of Science and Technology and Talent Team Plan of Guizhou province(GCC[2023]007)Guizhou Provincial Basic Research Program(Natural Science)(No.ZK[2025]Key 086)Fok Ying Tung Education Foundation(171095)financial support,Innovation Capability Support Program of Shaanxi(2024RS-CXTD-57)Innovation Foundation for Doctor Dissertation of Northwestern Polytechnical University(CX2024094)。
文摘The previous studies mainly focused on improving microwave absorbing(MA)performances of MA materials.Even so,these designed MA materials were very difficult to be employed in complex and changing environments owing to their single-functionalities.Herein,a combined Prussian blue analogues derived and catalytical chemical vapor deposition strategy was proposed to produce hierarchical cubic sea urchin-like yolk–shell CoNi@Ndoped carbon(NC)-CoNi@carbon nanotubes(CNTs)mixed-dimensional multicomponent nanocomposites(MCNCs),which were composed of zerodimensional CoNi nanoparticles,three-dimensional NC nanocubes and onedimensional CNTs.Because of good impedance matching and attenuation characteristics,the designed CoNi@NC-CoNi@CNTs mixed-dimensional MCNCs exhibited excellent MA performances,which achieved a minimum reflection loss(RL_(min))of−71.70 dB at 2.78 mm and Radar Cross section value of−53.23 dB m^(2).More importantly,the acquired results demonstrated that CoNi@NC-CoNi@CNTs MCNCs presented excellent photothermal,antimicrobial and anti-corrosion properties owing to their hierarchical cubic sea urchin-like yolk–shell structure,highlighting their potential multifunctional applications.It could be seen that this finding not only presented a generalizable route to produce hierarchical cubic sea urchin-like yolk–shell magnetic NC-CNTs-based mixed-dimensional MCNCs,but also provided an effective strategy to develop multifunctional MCNCs and improve their environmental adaptabilities.
文摘Foreword It is our great privilege,as vip Editors of the International Journal of Minerals,Metallurgy and Materials(IJMMM),to present this special issue on“High-Entropy and Multicomponent-Doped Materials for Energy Applications:Innovations in Energy Conversion and Storage.”This collection highlights the latest research developments in the preparation,optimizing properties,and exploring potential applications of high-entropy materials(HEMs)and other com-pounds with increased configurational entropy.
基金financial supports from National Key R&D Program of China(Grant No.2022YFA1205100,2022YFA1404600)National Natural Science Foundation of China(Grant Nos.12192251,12334014,12474325,12134001,12304418,12474378,12274133,12174107,12174113,12274130)+2 种基金the Innovation Program for Quantum Science and Technology(Grant No.2021ZD0301403)Shanghai Municipal Science and Technology Major Project(Grant No.2019SHZDZX01)Fundamental Research Funds for the Central Universities,the Engineering Research Center for Nanophotonics&Advanced Instrument,Ministry of Education,East China Normal University(No.2023nmc005).
文摘Miniaturized erbium-doped waveguide amplifiers attracted great interests in recent decades due to their high gain-efficiency and function-scalability in the telecom C-band.In this work,an erbium-doped thin film lithium niobate waveguide amplifier achieving>10 dB off-chip(fiber-to-fiber)net gain and>20 mW fiber-output amplified power is demonstrated,thanks to the low-propagation-loss waveguides and robust waveguide edge-couplers prepared by the photolithography assisted chemomechanical etching technique.Systematic investigation on the fabricated waveguide amplifiers reveals remarkable optical gain around the peak wavelength of 1532 nm as well as the low fiber-coupling loss of-1.2 dB/facet.A fiber Bragg-grating based waveguide laser is further demonstrated using the fabricated waveguide amplifier as the external gain chip,which generates>2 mW off-chip power continuous-wave lasing around the gain peak at 1532 nm.The unambiguous demonstration of fiber-to-fiber net gain of the erbium-doped thinfilm lithium niobate(TFLN)waveguide amplifier as well as its external gain chip application will benefit diverse fields demanding scalable gain elements with highspeed tunability.
基金National Natural Science Foundation of China(No.22272149,22062025)Yunnan University’s Research Innovation Fund for Graduate Students(No.KC-23234085)+1 种基金Workstation of Academician Chen Jing of Yunnan Province(No.202105AF150012)Free Exploration Fund for Academician(No.202405AA350001)。
文摘Electrocatalytic conversion of renewable biomass is emerging as a promising route for sustainable chemical production;hence it urgently calls for developing efficient electrocatalysts with low potentials and high current densities.Herein,a Pr-doped Co(OH)_(2)hexagonal sheet(Pr/Co=1/9,in mole)is synthesized by electrodeposition as highly performant catalyst for 5-hydroxymethylfurfural(HMF)oxidation reaction(HMFOR)to produce 2,5-furandicarboxylic acid(FDCA).This novel and low-cost catalyst possesses a rather low onset potential of 1.05 V(vs.RHE)and requires only 1.10 V(vs.RHE)to reach a current density of 10 mA cm^(-2)for HMFOR,significantly outperforming Co(OH)_(2)benchmark(i.e.,210 mV higher to reach10 m A cm^(-2)).The origin of Pr promotion effect as well as the evolution of CoOOH catalytic sites and HMFOR process has been deeply elucidated by physical characterizations,kinetic experiments,in situ electrochemical techniques,and theoretical calculations.The unique Pr-ameliorated CoOOH active centers enable 100%conversion of HMF,99.6%selectivity of FDCA,and 99.7%Faraday efficiency,with a superior cycling durability toward HMFOR.This can be one of the most outstanding results for Co-based HMFOR catalysts to date in the literature.Thereby this work can help open up new horizons for constructing novel and efficient Co-based electrocatalysts by the utilization of lanthanide elements.
基金funded by the Master,PhD Scholarship Programme of Vingroup Innovation Foundation(VINIF),code VINIF.2024.TS.035funded by Vietnam National University,Ho Chi Minh City(VNUHCM)under grant number NCM2024-18-01。
文摘In the past century,industrial and economic growth relied heavily on fossil fuels such as coal,oil,and natural gas.As the society energy demands continue to grow,these fossil fuel reserves are depleted,leading to significant environmental issues[1].Currently,sustainable biomass resources have attracted much attention as potential substitutes to fossil fuels for producing biofuels and commodity chemicals[2].
基金Project supported by the National Natural Science Foundation of China (12174075)the Scientific and Technological Bases and Talents of Guangxi (Guike AD21220016)+1 种基金Guangxi Science and Technology Major Project(AA23073018)the special fund for Guangxi Bagui Scholars。
文摘Mn^(2+)-doped CsPbCl_(3)(Mn^(2+):CsPbCl_(3)) nanocrystals(NCs) have attracted considerable attention due to their unique strong and broad orange-red emission band,presenting promising applications in the field of photoelectric devices.However,pristine Mn^(2+):CsPbCl_(3)NCs commonly suffer from low photoluminescence quantum yield(PL QY) and stability issues.Herein,we introduced europium ions(Eu^(3+))into Mn^(2+):CsPbCl_(3)NCs via the thermal injection synthesis method to obtain high performance Eu^(3+)and Mn^(2+)codoped CsPbCl_(3)(Eu^(3+)/Mn^(2+):CsPbCl_(3)) NCs.The maximum PL QY of the resulting Eu^(3+)/Mn^(2+):CsPbCl_(3)NCs reaches up to 90.92%.It is found that the doping of Eu^(3+)ions significantly reduces the non-radiative recombination caused by high defect states,and improves the energy transfer efficiency from exciton to Mn^(2+),thereby boosting the PL performance.Moreover,doping Eu^(3+)ions notably improves the UV-light and water stability of Mn^(2+):CsPbCl_(3)NCs.We further demonstrate the application versatility of Eu^(3+)/Mn^(2+):CsPbCl_(3)NCs in white light emitting diodes(WLEDs) and optical anticounterfeiting applications.This work provides a valuable perspective for the attainment of high performance Mn^(2+):CsPbCl_(3)NCs and lays a foundation for the codoping of other lanthanide ions to adjust the luminescence properties of Mn^(2+):CsPbCl_(3)NCs.
基金supported by the Natural Science Foundation of Guangdong Province(Nos.2023A1515010093)the Shenzhen Fundamental Research Program(Nos.JCYJ20220809170611004,20231121110828001 and 20231121113641002)the Taipei University of Technology-Shenzhen University Joint Research Program(No.2024001).
文摘In this paper,we have mainly studied the amplification effect of thulium-doped fiber amplifier(TDFA)at 2µm,and compared different amplification effects of the one-stage TDFA,two-stage TDFA and three-stage TDFA at proper conditions.The simulation results show that within the effective threshold,with the increase of the pump power,the amplification effect of the optical amplifier improves,but the signal-to-noise ratio(SNR)of the output signal decreases,in order to balance the gain benefit and noise coefficient of TDFA,we can use a multi-stage amplification structure.Three-stage backward-pumped series 2.06µm TDFA,whose slope efficiency can achieve 11%at certain condition.At 5.2 W pump power,the output signal gain of 2µm TDFA exceeds 20 dB,and the output SNR is higher than 32 dB.In addition,the effect of the optimum length of thulium-doped fiber on the amplification performance of 2µm TDFA is also analyzed in this paper.These simulation results are important for the experiment and design of 2µm TDFA.
基金Project supported by the National Natural Science Foundation of China(22268003,52272287)。
文摘It is anticipated to remove highly hazardous tetracycline antibiotic from aqueous solution photocatalytically by using Gd doped spinal ferrite.In this work,both ZnFe_(2)O_(4)and Gd doped ZnFe_(2)O_(4)photocatalysts were hydrothermally fabricated and characterized by different techniques.The spherical photocatalysts show extended photocatalytic removal efficiency under visible light.The optimized sample(ZnFe_(1.96)Cd_(0.04)O_(4))removes 78%antibiotic in 80 min.Moreover,under simulated solar light irradiation,the rate of hydrogen produced from water splitting photocatalysis with ZnFe_(1.96)Cd_(0.04)O_(4)reaches 230.4μmol/(g h).These increased activities are attributed to the increased specific surface area,the expanded light absorption range and the enhanced charge separation realized by doping Gd.According to the charge trapping study,both superoxide(·O_(2)^(-))and hydroxyl radicals(·OH)were the major active species in the process of removing antibiotic.This research provides a feasible way to fabricate low cost photocatalysts for the eradication of highly hazardous pollutants from aqueous solution.
基金supported by the National Natural Science Foundation of China(No.11304184)the Shandong University of Technology and Zibo City Integration Development Project(No.2019ZBXC120)。
文摘Based on the nonlinear saturable absorption properties(NSAPs)of a two-dimensional(2D)material of antimony selenide(Sb_(2)Se_(3)),a Q-switched erbium-doped fiber(EDF)laser is systematically demonstrated.The Sb_(2)Se_(3)nano sheets are prepared by liquid-phase exfoliation(LPE)method.After the sandwich-structured Sb_(2)Se_(3)saturable absorber(SA)is fabricated,the NSAPs are characterized and the modulation depth,the saturation intensity and the unsaturated loss are determined to be 25.2%,2.02 MW/cm^(2),and 3.29%,respectively.When the as-prepared Sb_(2)Se_(3)-SA is integrated into the ring cavity,the laser operates at a stable Q-switching regime in the pump power range of 100—400 mW.The laser oscillates at the central wavelength of 1558.48 nm with a 3 dB bandwidth of 2.32 nm.Take the advantages of the Sb_(2)Se_(3)-SA,the pulse duration can be compressed from 40.49 kHz to 128.12 kHz.At the pump power of 400 mW,the Q-switching laser gives the narrowest pulse duration the highest average output power,the largest pulse energy,and the signal-to-noise ratio(SNR)of 0.93μs,2.16 mW,16.89 nJ,and 53 dB,respectively.Our new attempt on Sb_(2)Se_(3)-based Q-switched EDF laser,combining the existing mode-locking achievements,proves that Sb_(2)Se_(3)is a powerful candidate for pulse compression due to the characteristics of high modulation depth and high stability.
