The development of quantum materials for single-photon emission is crucial for the advancement of quantum information technology.Although significant advancements have been witnessed in recent years for single-photon ...The development of quantum materials for single-photon emission is crucial for the advancement of quantum information technology.Although significant advancements have been witnessed in recent years for single-photon sources in the near-infrared band(λ∼700–1000 nm),several challenges have yet to be addressed for ideal single-photon emission at the telecommunication band.In this study,we present a droplet-epitaxy strategy for O-band to C-band single-photon source-based semiconductor quantum dots(QDs)using metal-organic vaporphase epitaxy(MOVPE).By investigating the growth conditions of the epitaxial process,we have successfully synthesized InAs/InP QDs with narrow emission lines spanning a broad spectral range of λ∼1200–1600 nm.The morphological and optical properties of the samples were characterized using atomic force microscopy and microphotoluminescence spectroscopy.The recorded single-photon purity of a plain QD structure reaches g^((2))(0)=0.16,with a radiative recombination lifetime as short as 1.5 ns.This work provides a crucial platform for future research on integrated microcavity enhancement techniques and coupled QDs with other quantum photonics in the telecom bands,offering significant prospects for quantum network applications.展开更多
Developing on-demand biomass valorization represents an ideal path to alleviate the double burden of a sustainable energy-environment future,yet exploring tunable lignin-first chemistry to accomplish multifunctional w...Developing on-demand biomass valorization represents an ideal path to alleviate the double burden of a sustainable energy-environment future,yet exploring tunable lignin-first chemistry to accomplish multifunctional water purification remains elusive.Herein,we report a versatile solvent-fractionation to construct heteroatom-doped multicolor lignin carbon quantum dots(CQDs)with the functions of bimodal pollutant sensing,metal-ionic visualization,and photocatalytic antibiotic dissociation.With the aid of oxidation cleavage and biphasic extraction,the underlying lignin features of molecular weight and functional linkages influence the quantum size and core-surface state of CQDs conferring the unique optical-structure-performance.The N,S co-doped blue-emitting CQDs via light-quenching offer the selective identification of Fe^(3+)-ions in a broad response range with an acceptable limit of detection.The addition of L-cysteine can efficiently restore the fluorescence of CQDs by forming a stable Fe^(3+)-L-cys complex.The green-emissive CQDs are facilely embedded into cellulose hydrogel to directly visualize the presence of metal-ions.A red-CQDs modified ternary ZnIn2S4(ZIS)composite is fabricated to achieve photocatalytic antibiotic removal with an efficiency of~85%.The excellent photo-generated electron and storage capabilities of CQDs improve the light-capturing,electron conduction,and charge carrier separation of ZIS.The reactive species are of importance to photocatalytic tetracycline oxidation,wherein the electron holes(h+)function as the main contributor followed by∙O_(2)^(-),1O2 and∙OH.The directly interfacial electron escaping-shuttling with the help of optimized electronic and energy-band structures is confirmed via electrochemical test and theoretical computation.We anticipate that the present work not only sheds substantial light to manipulate polychromatic lignin-based CQDs via a tailored solvent-engineering,but also presents an emerging green route of emphasizing biomass-water nexus.展开更多
Copper indium sulfur-based quantum dots(CIS QDs)are classified as one of well-known ternaryⅠ-Ⅲ-Ⅵsemiconductors,which have exciting promising applications in display and lighting devices,due to their unique merits s...Copper indium sulfur-based quantum dots(CIS QDs)are classified as one of well-known ternaryⅠ-Ⅲ-Ⅵsemiconductors,which have exciting promising applications in display and lighting devices,due to their unique merits such as non-toxicity,stability,and high photoluminescence quantum yield(PL QY).However,the emission full width at half maximum(FWHM)of CIS-based QDs typically extends to~140 nm,fundamentally limiting their use in high-color-purity light emitting.Herein,we report the rationally-designed CIS QDs with high efficiency and narrowband emission by chemical stoichiometry and gradient shell engineering,based on precisely controlling the dynamic growth and stoichiometric ratio.It is found that the accurate control on the growth kinetics and stoichiometry during the nucleation process of CIS QDs could enhance the crystallinity through gradual and organized crystalline growth,which effectively mitigates the formation of InCusubstitutional and Cu vacancies,thus suppressing the defect emission.Furthermore,the introduced InSx/ZnxGa_(1-x)S gradient shell on the surface of QDs cores could reduce the strain within interface,thereby eliminating the non-radiative recombination caused by the surface defects resulted from interface strain.As a result,a remarkable PLQY of 89%is achieved for the QDs.More importantly,their FWHM decreases to 70 nm,which is the narrowest one for CIS-based QDs ever reported,representing their bright future to be applied in high-definition display devices.展开更多
Flexible materials with perovskite quantum dots(PQDs)are widely used in the field of photonics and opto-electronics due to their unique properties.Development of new materials based on these nanoparticles,incorporated...Flexible materials with perovskite quantum dots(PQDs)are widely used in the field of photonics and opto-electronics due to their unique properties.Development of new materials based on these nanoparticles,incorporated into flexible and lightweight nonwoven fabrics,demonstrated high photoconductivity and efficient light energy conversion.In this work,we propose a method for creating a stable luminescent nonwoven material using electrospinning,in which inorganic salt precursors are used without the need for additional stabilizers.Equimolar solutions of cesium and lead(Ⅱ)bromide were mixed with a fluoroplast,resulting in a series of samples.Luminescent materials were obtained containing PQDs with a composition of CsPbBr_(3),with emission peaks ranging from 507 to 517 nm under 365-nm excitation.We have experimentally established and theoretically confirmed that the peak position is related to the size of the particles formed in the fiber during electrospinning and depends on processing time.Developed materials exhibited stable luminescent properties for up to 2.5 years,making them a promising candidate for the development of new flexible optoelectronic devices based on PQDs.展开更多
As an important index to measure the degree of entanglement in quantum systems,concurrence plays an important role in practical research.In this paper,we study the concurrence between two qubits in triangular triple q...As an important index to measure the degree of entanglement in quantum systems,concurrence plays an important role in practical research.In this paper,we study the concurrence between two qubits in triangular triple quantum dot structure.Through calculation and simulation,it is found that concurrence is mainly affected by the interdot coupling strength t,Coulomb interactionU,temperature T,and electrode coupling G.Through comparative studies with parallel triple quantum dot structures,we demonstrate that the triangular geometry exhibits significantly enhanced concurrence under identical conditions.In addition,under the condition that concurrence exceeds 0.9,the functional relationship between t and U is obtained through simulation,which provides theoretical support for quantum dot regulation under high entanglement.Finally,we demonstrate the feasibility of implementing a three-qubit quantum gate,using the Toffoli gate as a representative example,under the condition that the triangular triple quantum dot system maintains high entanglement.展开更多
A solvothermal approach was used to generate N-doped graphene oxide quantum dots(NGOQDs)using MoS_(2) and Al_(2)O_(3)nanocomposites.Through the use of TEM,XRD,Raman,ATR-FTIR,and XPS,the produced composites'shape,c...A solvothermal approach was used to generate N-doped graphene oxide quantum dots(NGOQDs)using MoS_(2) and Al_(2)O_(3)nanocomposites.Through the use of TEM,XRD,Raman,ATR-FTIR,and XPS,the produced composites'shape,composition,and structure were described.Tribological behavior and lubrication properties of NGOQDsMoS_(2) and NGOQDs-Al_(2)O_(3)nanocomposites as additive in nanofluids during hot roll cladding of copper and steel were studied and rolling lubrication mechanism was disclosed.The outcome demonstrates that tribological performance may be greatly enhanced by combining NGOQDs,and surface quality of the rolled copper and steel,and the addition of NGOQDs-MoS_(2) and NGOQDs-Al_(2)O_(3)nanoparticles can further improve the hot-rolling lubrication properties.The tribofilm,formed through the tribochemically induced lubrication process,significantly enhances the wear and corrosion resistance of rolled copper and steel surfaces.展开更多
Quantum dots(QDs)can modulate the solar spectrum through the down-conversion mechanism to better match the spectral response of solar cells.Following previous work,this paper first tested the response of QD solar cell...Quantum dots(QDs)can modulate the solar spectrum through the down-conversion mechanism to better match the spectral response of solar cells.Following previous work,this paper first tested the response of QD solar cells to specific monochromatic light,and found that QDs can effectively improve the photoelectric conversion efficiency(PCE)in the ultraviolet(UV)band by comparison.Then the photoelectric properties of the QD solar cells are tested under the air-mass 1.5(AM1.5)and air-mass 0(AM0)spectra.The experimental results show that because the absorption band of QDs is in the UV region,the space solar cells in the AM0 spectrum can obtain better PCE after coating QDs.The research results show the technical route of space solar cells with down-conversion mechanism,and put forward an important direction for the application of space solar photovoltaic(PV)technology,and have a good application prospect.展开更多
Colloidal quantum dots(CQDs)are highly regarded for their outstanding photovoltaic characteristics,including excellent color purity,stability,high photoluminescence quantum yield(PLQY),narrow emission spectra,and ease...Colloidal quantum dots(CQDs)are highly regarded for their outstanding photovoltaic characteristics,including excellent color purity,stability,high photoluminescence quantum yield(PLQY),narrow emission spectra,and ease of solution processing.Despite significant progress in quantum dot light-emitting diodes(QLEDs)technology since its inception in 1994,blue QLEDs still fall short in efficiency and lifespan compared to red and green versions.The toxicity concerns associated with Cd/Pb-based quantum dots(QDs)have spurred the development of heavy-metal-free alternatives,such as groupⅡ−Ⅵ(e.g.,ZnSe-based QDs),groupⅢ−Ⅴ(e.g.,InP,GaN QDs),and carbon dots(CDs).In this review,we discuss the key properties and development history of quantum dots(QDs),various synthesis approaches,the role of surface ligands,and important considerations in developing core/shell(C/S)structured QDs.Additionally,we provide an outlook on the challenges and future directions for blue QLEDs.展开更多
Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)(PEDOT:PSS)is a highly successful conductive polymer utilized as an electrode material in energy storage units for portable and wearable electronic de-vices.Neve...Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)(PEDOT:PSS)is a highly successful conductive polymer utilized as an electrode material in energy storage units for portable and wearable electronic de-vices.Nevertheless,employing PEDOT:PSS in supercapacitors(SC)in its pristine state presents challenges due to its suboptimal electrochemical performance and operational instability.To surmount these limita-tions,PEDOT:PSS has been integrated with carbon-based materials to form flexible electrodes,which ex-hibit physical and chemical stability during SC operation.We developed a streamlined fabrication process for high-performance SC electrodes composed of PEDOT:PSS and carbon quantum dots(CQDs).The CQDs were synthesized under microwave irradiation,yielding green-and red-light emissions.Through optimiz-ing the ratios of CQDs to PEDOT:PSS,the SC electrodes were prepared using a spray-coating technique,marking a significant improvement in device performance with a high volumetric capacitance(104.10 F cm-3),impressive energy density(19.68 Wh cm^(-3)),and excellent cyclic stability,retaining~85% of its original volumetric capacitance after 15,000 repeated GCD cycles.Moreover,the SCs,when utilized as a flexible substrate,demonstrated the ability to maintain up to~85% of their electrochemical performance even after 3,000 bending cycles(at a bending angle of 60°).These attributes render this hybrid composite an ideal candidate for a lightweight smart energy storage component in portable and wearable electronic technologies.展开更多
Aqueous zinc ion batteries have received widespread attention.However,the growth of zinc dendrites and hydrogen evolution reaction generation seriously hinder the practical application of zinc ion bat-teries.Herein,it...Aqueous zinc ion batteries have received widespread attention.However,the growth of zinc dendrites and hydrogen evolution reaction generation seriously hinder the practical application of zinc ion bat-teries.Herein,it is reported that a multifunctional dendrites-free low-temperature PVA-based gel elec-trolyte by introducing negatively charged polymer carbon quantum dots(QDs)and the organic antifreeze dimethyl sulfoxide(DMSO)into it.The QDs carrying a large number of functional groups on the surface can effectively adsorb Zn^(2+),eliminating the“tip effect”,and inducing the uniform deposition of Zn^(2+)and the formation of a dendrites-free structure.Meanwhile,the solvation structure of adsorbed Zn^(2+)can be controlled by charged groups to reduce the generation of side reactions,thus obtaining high-performance zinc ion batteries.The Zn/polyaniline(PANi)full battery can be stably cycled more than 1000 times at-20℃,and the design of this gel electrolyte can provide good feasibility for safe,stable,and flexible energy storage devices.展开更多
Carbon quantum dots are a new type of fluorescent nanomaterials with broad applications in drug delivery,bioimaging,solar cells,and photocatalysis due to their unique biocompatibility,optical properties and easy funct...Carbon quantum dots are a new type of fluorescent nanomaterials with broad applications in drug delivery,bioimaging,solar cells,and photocatalysis due to their unique biocompatibility,optical properties and easy functionalization.In the meantime,because of its high carbon content,renewable nature,and environmental friendliness,lignin has drawn the attention of researchers as a desirable raw material for creating carbon quantum dots.Here we review the synthesis of carbon quantum dots from lignin,focusing on synthetic methods,properties,and applications in energy,and photocatalysis.Later,we propose some new development prospects from preparation methods,luminescence mechanism research,application,and commercial cost of lignin carbon quantum dots.Finally,based on this,the development prospects of this field are prospected and summarized.展开更多
Quantum dots(QDs),a type of nanoscale semiconductor material with unique optical and electrical properties like adjustable emission and high photoluminescence quantum yields,are suitable for applications in optoelectr...Quantum dots(QDs),a type of nanoscale semiconductor material with unique optical and electrical properties like adjustable emission and high photoluminescence quantum yields,are suitable for applications in optoelectronics.However,QDs are typically degraded under humid and high-temperature circumstances,greatly limiting their practical value.Coating the QD surface with an inorganic silica layer is a feasible method for improving stability and endurance in a variety of applications.This paper comprehensively reviews silica coating methodologies on QD surfaces and explores their applications in optoelectronic domains.Firstly,the paper provides mainstream silica coating approaches,which can be divided into two categories:in-situ hydrolysis of silylating reagents on QD surfaces and template techniques for encapsulation QDs.Subsequently,the recent applications of the silica-coated QDs on optoelectronic fields including light-emitting diodes,solar cells,photodetectors were discussed.Finally,it reviews recent advances in silica-coated QD technology and prospects for future applications.展开更多
With the rapid development of electric vehicles,hybrid electric vehicles and smart grids,people's demand for large-scale energy storage devices is increasingly intense.As a new type of secondary battery,potassium ...With the rapid development of electric vehicles,hybrid electric vehicles and smart grids,people's demand for large-scale energy storage devices is increasingly intense.As a new type of secondary battery,potassium ion battery is promising to replace the lithium-ion battery in the field of large-scale energy storage by virtue of its low price and environmental friendliness.At present,the research on the anode materials of potassium ion batteries mainly focuses on carbon materials and the design of various nanostructured metal-based materials.Problems such as poor rate performance and inferior cycle life caused by electrode structure comminution during charge and discharge have not been solved.Quantum dots/nanodots materials are a new type of nanomaterials that can effectively improve the utilization of electrode materials and reduce production costs.In addition,quantum dots/nanodots materials can enhance the electrode reaction kinetics,reduce the stress generated in cycling,and effectively alleviate the agglomeration and crushing of electrode materials.In this review,we will systematically introduce the synthesis methods,K+storage properties and K+storage mechanisms of carbon quantum dots and carbon-based transition metal compound quantum dots composites.This review will have significant references for potassium ion battery researchers.展开更多
The growing environmental concerns regarding rare earth elements in fluorescent powders,along with high production costs,have increased the demand for sustainable alternatives.We propose a promising solution using lum...The growing environmental concerns regarding rare earth elements in fluorescent powders,along with high production costs,have increased the demand for sustainable alternatives.We propose a promising solution using luminescent metal-organic frameworks(LMOFs)with large surface areas and tunable pore structures,combined with organic carbon quantum dots(CQDs).This study develops a novel white lightemitting diode(WLED)fluorescent powder by incorporating yellow-fluorescent quantum dots(CQDs-Y)into blue-emitting LMOF(ZJU-28),forming the composite material CQDs-Y-n@ZJU-28.The composite exhibits excellent thermal and chemical stability,long-term storage performance,and emits warm white light(CIE:0.3277,0.3281)when subjected to excitation at 365 nm,along with an external quantum efficiency(EQE)of 8.85%.Furthermore,it exhibits tunable emission characteristics and promising LED performance,showcasing a color rendering index(CRI)of 78 and a correlated color temperature of 3384 K.The emitted light undergoes minimal deviation in color towards the white end of the spectrum in the temperature range of 277-437 K,making it an ideal candidate for advanced WLED applications.展开更多
Colloidal quantum dots(CQDs)are affected by the quantum confinement effect,which makes their bandgap tunable.This characteristic allows these materials to cover a broader infrared spectrum,providing a costeffective al...Colloidal quantum dots(CQDs)are affected by the quantum confinement effect,which makes their bandgap tunable.This characteristic allows these materials to cover a broader infrared spectrum,providing a costeffective alternative to traditional infrared detector technology.Recently,thanks to the solution processing properties of quantum dots and their ability to integrate with silicon-based readout circuits on a single chip,infrared detectors based on HgTe CQDs have shown great application prospects.However,facing the challenges of vertically stacked photovoltaic devices,such as barrier layer matching and film non-uniformity,most devices integrated with readout circuits still use a planar structure,which limits the efficiency of light absorption and the effective separation and collection of photo-generated carriers.Here,by synthesizing high-quality HgTe CQDs and precisely controlling the interface quality,we have successfully fabricated a photovoltaic detector based on HgTe and ZnO QDs.At a working temperature of 80 K,this detector achieved a low dark current of 5.23×10^(-9)A cm^(-2),a high rectification ratio,and satisfactory detection sensitivity.This work paves a new way for the vertical integration of HgTe CQDs on silicon-based readout circuits,demonstrating their great potential in the field of high-performance infrared detection.展开更多
Calcium ions(Ca^(2+))and manganese ions(Mn^(2+))are essential for sustaining life activities and are key monitoring indicators in drinking water.Developing highly sensitive,selective,and portable detection methods for...Calcium ions(Ca^(2+))and manganese ions(Mn^(2+))are essential for sustaining life activities and are key monitoring indicators in drinking water.Developing highly sensitive,selective,and portable detection methods for Ca^(2+)and Mn^(2+)is significant for water quality monitoring and human health.In this paper,blue fluorescent Ti3C2 MXene-based quantum dots(MQDs,λ_(em)=445 nm)are prepared using Ti_(3)C_(2)MXene as the precursor.Through the chelation effect of ethylene diamine tetraacetic acid(EDTA),a blue and red dual-emission fluorescent probe,MQDs-EDTA-Eu^(3+)-DPA,was constructed.Herein,dipicolinic acid(DPA)acts as an absorbing ligand and significantly enhances the red fluorescence of europium ions(Eu^(3+))at 616 nm through the“antenna effect”.The blue fluorescence of MQDs serves as an internal reference signal.High concentrations of Ca^(2+)can quench the red fluorescence of Eu^(3+)-DPA;Mn^(2+)can be excited to emit purple fluorescence at 380 nm after coordinating with DPA,red fluorescence of Eu^(3+)-DPA serves as the internal reference signal.Based on the above two fluorescence intensity changes,ratiometric fluorescence detection methods for Ca^(2+)and Mn^(2+)are established.The fluorescence intensity ratio(IF_(616)/IF_(445))exhibits a linear relationship with Ca^(2+)in the range of 35-120μmol/L,with a detection limit of 5.98μmol/L.The fluorescence intensity ratio(IF_(380)/IF_(616))shows good linearity with Mn^(2+)in the range of 0-14μmol/L,with a detection limit of 28.6 nmol/L.This method was successfully applied to the quantitative analysis of Ca^(2+)and Mn^(2+)in commercially available mineral water(Nongfu Spring,Ganten,and Evergrande),with recovery rates of 80.6%-117%and relative standard deviations(RSD)of 0.76%-4.6%.Additionally,by preparing MQD-based fluorescent test strips,visual detections of Ca^(2+)and Mn^(2+)are achieved.This work demonstrates the application potential of MQDs in the field of visual fluorescence sensing of ions in water quality.展开更多
The discovery of quantum dots(QDs)stands as one of the paramount technological breakthroughs of the 20th century.Their versatility spans from everyday applications to cutting-edge scientific research,encompassing area...The discovery of quantum dots(QDs)stands as one of the paramount technological breakthroughs of the 20th century.Their versatility spans from everyday applications to cutting-edge scientific research,encompassing areas such as displays,lighting,photocatalysis,bio-imaging,and photonics devices and so on.Among the myriad QDs technologies,industrially relevant CuInS_(2)(CIS)QDs have emerged as promising alternatives to traditional Cd-and Pb-based QDs.Their tunable optoelectronic properties,high absorption coefficient,compositional flexibility,remarkable stability as well as Restriction of Hazardous Substances-compliance,with recent trends revealing a renewed interest in this material for various visible and near-infrared technological applications.This review focuses on recent advancements in CIS QDs as multidisciplinary field from its genesis in the mid-1990 to date with an emphasis on key breakthroughs in their synthesis,surface chemistry,post-synthesis modifications,and various applications.First,the comparation of properties of CIS QDs with relevant knowledge from other classes of QDs and from Ⅰ-Ⅱ-Ⅲ semiconductors as well is summarized.Second,recent advances in the synthesis methods,structure-optoelectronic properties,their defects,and passivation strategies as well as CIS-based heterostructures are discussed.Third,the state-of-the-art applications of CIS QDs ranging from solar cells,luminescence solar concentrations,photocatalysis,light emitting diodes,bioimaging and some emerging applications are summarized.Finally,we discuss open challenges and future perspectives for further advancement in this field.展开更多
Hybrid organic–inorganic lead halide perovskites have emerged as a promising material for high-efficiency solar cells,yet challenges related to crystallization and defects limit their performance and stability.This s...Hybrid organic–inorganic lead halide perovskites have emerged as a promising material for high-efficiency solar cells,yet challenges related to crystallization and defects limit their performance and stability.This study investigates the use of perovskite quantum dots(QDs)as crystallization seeds to enhance the quality of FAPbI_(3)perovskite films and improve the performance of perovskite solar cells(PSCs).We demonstrate that CsPbI_(3)and CsPbBr_(3)QDs effectively guide the crystallization process,leading to the formation of larger crystals with preferential orientations,particularly the(001)and(002)planes,which are associated with reduced defect densities.This seedmediated growth strategy resulted in PSCs with power conversion efficiencies(PCEs)of 24.75%and 24.11%,respectively,compared to the baseline efficiency of 22.05%for control devices.Furthermore,devices incorporating QD-treated perovskite films exhibited remarkable stability,maintaining over 80%of their initial PCE after 1000 h of simulated sunlight exposure,a significant improvement over the control.Detailed optoelectronic characterization revealed reduced non-radiative recombination and enhanced charge transport in QD-treated devices.These findings highlight the potential of QDs as a powerful tool to improve perovskite crystallization,facet orientation,and overall device performance,offering a promising route to enhance both efficiency and stability in PSCs.展开更多
Metal halide perovskites exhibit excellent absorption properties,high carrier mobility,and remarkable charge transfer ability,showcasing significant potential as light harvesters in new-generation photovoltaic and opt...Metal halide perovskites exhibit excellent absorption properties,high carrier mobility,and remarkable charge transfer ability,showcasing significant potential as light harvesters in new-generation photovoltaic and optoelectronic technologies.Their development has seen unprecedented growth since their discovery.Similar to metal halide perovskite developments,perovskite quantum dots(PQDs)have demonstrated significant versatility in terms of shape,dimension,bandgap,and optical properties,making them suitable for the development of optoelectronic devices.This review discusses various fabrication methods of PQDs,delves into their degradation mechanisms,and explores strategies for enhancing their performance with their applications in a variety of technological fields.Their elevated surface-to-volume ratio highlights their importance in increasing solar cell efficiency.PQDs are also essential for increasing the performance of perovskite solar cells,photodetectors,and lightemitting diodes,which makes them indispensable for solid-state lighting applications.PQDs'unique optoelectronic characteristics make them suitable for sophisticated sensing applications,giving them greater capabilities in this field.Furthermore,PQDs'resistive switching behavior makes them a good fit for applications in memory devices.PQDs'vast potential also encompasses the fields of quantum optics and communication,especially for uses like nanolasers and polarized light detectors.Even though stability and environmental concerns remain major obstacles,research efforts are being made to actively address these issues,enabling PQDs to obtain their full potential in device applications.Simply put,understanding PQDs'real potential lies in overcoming obstacles and utilizing their inherent qualities.展开更多
Graphene quantum dots(GQDs)are a class of promising carbon-based nanomaterials that have attracted considerable interest from researchers due to their excellent physical,chemical,and biological properties.However,the ...Graphene quantum dots(GQDs)are a class of promising carbon-based nanomaterials that have attracted considerable interest from researchers due to their excellent physical,chemical,and biological properties.However,the high cost,toxicity,and laborious preparation process of GQDs also limit their widespread use.To address this issue,the actual research directions consist in replacing traditional non-renewable feedstocks via screening cheap,easily available,and renewable biomass materials based on the concept of resource conservation and environmental friendliness.Herein,the state-of-the-art technologies in the green preparation of GQDs using biomass as carbon source are reported.Initially,the green synthesis strategies as well as the structural,optical,and biosafety properties of GQDs are discussed in detail.Subsequently,the most representative applications of GQDs in energy and environmental remediation fields are summarized.Finally,the current challenges and future potential of the GQDs are presented.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos.12494604,12393834,12393831,62274014,6223501662335015)the National Key R&D Program of China (Grant No.2024YFA1208900)。
文摘The development of quantum materials for single-photon emission is crucial for the advancement of quantum information technology.Although significant advancements have been witnessed in recent years for single-photon sources in the near-infrared band(λ∼700–1000 nm),several challenges have yet to be addressed for ideal single-photon emission at the telecommunication band.In this study,we present a droplet-epitaxy strategy for O-band to C-band single-photon source-based semiconductor quantum dots(QDs)using metal-organic vaporphase epitaxy(MOVPE).By investigating the growth conditions of the epitaxial process,we have successfully synthesized InAs/InP QDs with narrow emission lines spanning a broad spectral range of λ∼1200–1600 nm.The morphological and optical properties of the samples were characterized using atomic force microscopy and microphotoluminescence spectroscopy.The recorded single-photon purity of a plain QD structure reaches g^((2))(0)=0.16,with a radiative recombination lifetime as short as 1.5 ns.This work provides a crucial platform for future research on integrated microcavity enhancement techniques and coupled QDs with other quantum photonics in the telecom bands,offering significant prospects for quantum network applications.
基金the National Natural Science Foundation of China(32171728 and 22008159)Wuhan Knowledge Innovation Project(2022020801020312).
文摘Developing on-demand biomass valorization represents an ideal path to alleviate the double burden of a sustainable energy-environment future,yet exploring tunable lignin-first chemistry to accomplish multifunctional water purification remains elusive.Herein,we report a versatile solvent-fractionation to construct heteroatom-doped multicolor lignin carbon quantum dots(CQDs)with the functions of bimodal pollutant sensing,metal-ionic visualization,and photocatalytic antibiotic dissociation.With the aid of oxidation cleavage and biphasic extraction,the underlying lignin features of molecular weight and functional linkages influence the quantum size and core-surface state of CQDs conferring the unique optical-structure-performance.The N,S co-doped blue-emitting CQDs via light-quenching offer the selective identification of Fe^(3+)-ions in a broad response range with an acceptable limit of detection.The addition of L-cysteine can efficiently restore the fluorescence of CQDs by forming a stable Fe^(3+)-L-cys complex.The green-emissive CQDs are facilely embedded into cellulose hydrogel to directly visualize the presence of metal-ions.A red-CQDs modified ternary ZnIn2S4(ZIS)composite is fabricated to achieve photocatalytic antibiotic removal with an efficiency of~85%.The excellent photo-generated electron and storage capabilities of CQDs improve the light-capturing,electron conduction,and charge carrier separation of ZIS.The reactive species are of importance to photocatalytic tetracycline oxidation,wherein the electron holes(h+)function as the main contributor followed by∙O_(2)^(-),1O2 and∙OH.The directly interfacial electron escaping-shuttling with the help of optimized electronic and energy-band structures is confirmed via electrochemical test and theoretical computation.We anticipate that the present work not only sheds substantial light to manipulate polychromatic lignin-based CQDs via a tailored solvent-engineering,but also presents an emerging green route of emphasizing biomass-water nexus.
基金supported by“Science and Technology Innovation 2025”of Ningbo Foundation(No.2020Z061)the general scientific research project of the Department of Education of Zhejiang Province(Nos.Y202147973 and Y202250313)+2 种基金Scientific Research Project Funded by Ningbo University of Technology(Nos.2022KQ11 and 2022TS26)National Natural Science Foundation of China(No.62165001)the special fund for“Guangxi Bagui Scholars”。
文摘Copper indium sulfur-based quantum dots(CIS QDs)are classified as one of well-known ternaryⅠ-Ⅲ-Ⅵsemiconductors,which have exciting promising applications in display and lighting devices,due to their unique merits such as non-toxicity,stability,and high photoluminescence quantum yield(PL QY).However,the emission full width at half maximum(FWHM)of CIS-based QDs typically extends to~140 nm,fundamentally limiting their use in high-color-purity light emitting.Herein,we report the rationally-designed CIS QDs with high efficiency and narrowband emission by chemical stoichiometry and gradient shell engineering,based on precisely controlling the dynamic growth and stoichiometric ratio.It is found that the accurate control on the growth kinetics and stoichiometry during the nucleation process of CIS QDs could enhance the crystallinity through gradual and organized crystalline growth,which effectively mitigates the formation of InCusubstitutional and Cu vacancies,thus suppressing the defect emission.Furthermore,the introduced InSx/ZnxGa_(1-x)S gradient shell on the surface of QDs cores could reduce the strain within interface,thereby eliminating the non-radiative recombination caused by the surface defects resulted from interface strain.As a result,a remarkable PLQY of 89%is achieved for the QDs.More importantly,their FWHM decreases to 70 nm,which is the narrowest one for CIS-based QDs ever reported,representing their bright future to be applied in high-definition display devices.
基金supported by the Russian Science Foundation grant number 24-23-00481,https://rscf.ru/project/24-2300481/.
文摘Flexible materials with perovskite quantum dots(PQDs)are widely used in the field of photonics and opto-electronics due to their unique properties.Development of new materials based on these nanoparticles,incorporated into flexible and lightweight nonwoven fabrics,demonstrated high photoconductivity and efficient light energy conversion.In this work,we propose a method for creating a stable luminescent nonwoven material using electrospinning,in which inorganic salt precursors are used without the need for additional stabilizers.Equimolar solutions of cesium and lead(Ⅱ)bromide were mixed with a fluoroplast,resulting in a series of samples.Luminescent materials were obtained containing PQDs with a composition of CsPbBr_(3),with emission peaks ranging from 507 to 517 nm under 365-nm excitation.We have experimentally established and theoretically confirmed that the peak position is related to the size of the particles formed in the fiber during electrospinning and depends on processing time.Developed materials exhibited stable luminescent properties for up to 2.5 years,making them a promising candidate for the development of new flexible optoelectronic devices based on PQDs.
文摘As an important index to measure the degree of entanglement in quantum systems,concurrence plays an important role in practical research.In this paper,we study the concurrence between two qubits in triangular triple quantum dot structure.Through calculation and simulation,it is found that concurrence is mainly affected by the interdot coupling strength t,Coulomb interactionU,temperature T,and electrode coupling G.Through comparative studies with parallel triple quantum dot structures,we demonstrate that the triangular geometry exhibits significantly enhanced concurrence under identical conditions.In addition,under the condition that concurrence exceeds 0.9,the functional relationship between t and U is obtained through simulation,which provides theoretical support for quantum dot regulation under high entanglement.Finally,we demonstrate the feasibility of implementing a three-qubit quantum gate,using the Toffoli gate as a representative example,under the condition that the triangular triple quantum dot system maintains high entanglement.
基金the support provided by the Natural Science Foundation of Jiangsu(No.BK20231355)the major project of Nanjing Institute of Technology,China Innovation Fund(No.CKJA202201)Qinglan Project of Jiangsu Province,the Major project of Basic Science(Natural science)research in colleges and universities of Jiangsu Province(No.23KJA430009)。
文摘A solvothermal approach was used to generate N-doped graphene oxide quantum dots(NGOQDs)using MoS_(2) and Al_(2)O_(3)nanocomposites.Through the use of TEM,XRD,Raman,ATR-FTIR,and XPS,the produced composites'shape,composition,and structure were described.Tribological behavior and lubrication properties of NGOQDsMoS_(2) and NGOQDs-Al_(2)O_(3)nanocomposites as additive in nanofluids during hot roll cladding of copper and steel were studied and rolling lubrication mechanism was disclosed.The outcome demonstrates that tribological performance may be greatly enhanced by combining NGOQDs,and surface quality of the rolled copper and steel,and the addition of NGOQDs-MoS_(2) and NGOQDs-Al_(2)O_(3)nanoparticles can further improve the hot-rolling lubrication properties.The tribofilm,formed through the tribochemically induced lubrication process,significantly enhances the wear and corrosion resistance of rolled copper and steel surfaces.
基金supported by the Science&Technology Development Fund of Tianjin Education Commission for Higher Education(No.2022KJ133).
文摘Quantum dots(QDs)can modulate the solar spectrum through the down-conversion mechanism to better match the spectral response of solar cells.Following previous work,this paper first tested the response of QD solar cells to specific monochromatic light,and found that QDs can effectively improve the photoelectric conversion efficiency(PCE)in the ultraviolet(UV)band by comparison.Then the photoelectric properties of the QD solar cells are tested under the air-mass 1.5(AM1.5)and air-mass 0(AM0)spectra.The experimental results show that because the absorption band of QDs is in the UV region,the space solar cells in the AM0 spectrum can obtain better PCE after coating QDs.The research results show the technical route of space solar cells with down-conversion mechanism,and put forward an important direction for the application of space solar photovoltaic(PV)technology,and have a good application prospect.
基金supported by the National Key Research and Development Program of China(2024YFE0103600)the National Natural Science Foundation of China(NSFC)(62474119,62205230,and 62175171)Suzhou Key Laboratory of Functional Nano&Soft Materials,Collaborative Innovation Center of Suzhou Nano Science&Technology,the 111 Project,Joint International Research Laboratory of Carbon-Based Functional Materials and Devices.
文摘Colloidal quantum dots(CQDs)are highly regarded for their outstanding photovoltaic characteristics,including excellent color purity,stability,high photoluminescence quantum yield(PLQY),narrow emission spectra,and ease of solution processing.Despite significant progress in quantum dot light-emitting diodes(QLEDs)technology since its inception in 1994,blue QLEDs still fall short in efficiency and lifespan compared to red and green versions.The toxicity concerns associated with Cd/Pb-based quantum dots(QDs)have spurred the development of heavy-metal-free alternatives,such as groupⅡ−Ⅵ(e.g.,ZnSe-based QDs),groupⅢ−Ⅴ(e.g.,InP,GaN QDs),and carbon dots(CDs).In this review,we discuss the key properties and development history of quantum dots(QDs),various synthesis approaches,the role of surface ligands,and important considerations in developing core/shell(C/S)structured QDs.Additionally,we provide an outlook on the challenges and future directions for blue QLEDs.
基金supported by the National Research Foundation of Korea(NRF)through a grant provided by the Korean government(No.NRF-2021R1F1A1063451).
文摘Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)(PEDOT:PSS)is a highly successful conductive polymer utilized as an electrode material in energy storage units for portable and wearable electronic de-vices.Nevertheless,employing PEDOT:PSS in supercapacitors(SC)in its pristine state presents challenges due to its suboptimal electrochemical performance and operational instability.To surmount these limita-tions,PEDOT:PSS has been integrated with carbon-based materials to form flexible electrodes,which ex-hibit physical and chemical stability during SC operation.We developed a streamlined fabrication process for high-performance SC electrodes composed of PEDOT:PSS and carbon quantum dots(CQDs).The CQDs were synthesized under microwave irradiation,yielding green-and red-light emissions.Through optimiz-ing the ratios of CQDs to PEDOT:PSS,the SC electrodes were prepared using a spray-coating technique,marking a significant improvement in device performance with a high volumetric capacitance(104.10 F cm-3),impressive energy density(19.68 Wh cm^(-3)),and excellent cyclic stability,retaining~85% of its original volumetric capacitance after 15,000 repeated GCD cycles.Moreover,the SCs,when utilized as a flexible substrate,demonstrated the ability to maintain up to~85% of their electrochemical performance even after 3,000 bending cycles(at a bending angle of 60°).These attributes render this hybrid composite an ideal candidate for a lightweight smart energy storage component in portable and wearable electronic technologies.
基金supported by the National Natural Science Foundation of China Project(No.52163001)the Guizhou Minzu University Research Platform Grant(No.GZMUGCZX[2021]01)+2 种基金the Guizhou Provincial Science and Technology Program Project Grant(Qiankehe Platform Talents-CXTD[2021]005,Qiankehe Platform Talents-GCC[2022]010-1,Qiankehe Fuqi[2023]001)the Central Guided Local Science and Technology Development Funds Project(Qiankehe Zhong Yindi[2023]035)the Doctor Startup Fund of Guizhou Minzu University(Grant No.GZMUZK[2024]QD77).
文摘Aqueous zinc ion batteries have received widespread attention.However,the growth of zinc dendrites and hydrogen evolution reaction generation seriously hinder the practical application of zinc ion bat-teries.Herein,it is reported that a multifunctional dendrites-free low-temperature PVA-based gel elec-trolyte by introducing negatively charged polymer carbon quantum dots(QDs)and the organic antifreeze dimethyl sulfoxide(DMSO)into it.The QDs carrying a large number of functional groups on the surface can effectively adsorb Zn^(2+),eliminating the“tip effect”,and inducing the uniform deposition of Zn^(2+)and the formation of a dendrites-free structure.Meanwhile,the solvation structure of adsorbed Zn^(2+)can be controlled by charged groups to reduce the generation of side reactions,thus obtaining high-performance zinc ion batteries.The Zn/polyaniline(PANi)full battery can be stably cycled more than 1000 times at-20℃,and the design of this gel electrolyte can provide good feasibility for safe,stable,and flexible energy storage devices.
基金Sponsorship Program by CAST(2023QNRC001)University-Industry Collaborative Education Program(220901115200913,220901115201954)+2 种基金Hunan Provincial Natural Science Foundation of China(2022JJ40007)Jiangsu Agricultural Science and Technology Innovation Fund(CX(22)3047)the National Natural Science Foundation of China(32201491)。
文摘Carbon quantum dots are a new type of fluorescent nanomaterials with broad applications in drug delivery,bioimaging,solar cells,and photocatalysis due to their unique biocompatibility,optical properties and easy functionalization.In the meantime,because of its high carbon content,renewable nature,and environmental friendliness,lignin has drawn the attention of researchers as a desirable raw material for creating carbon quantum dots.Here we review the synthesis of carbon quantum dots from lignin,focusing on synthetic methods,properties,and applications in energy,and photocatalysis.Later,we propose some new development prospects from preparation methods,luminescence mechanism research,application,and commercial cost of lignin carbon quantum dots.Finally,based on this,the development prospects of this field are prospected and summarized.
基金supported by the National Natural Science Foundation of China(Nos.62374142 and 22005255)Fundamental Research Funds for the Central Universities(Nos.20720220085 and 20720240064)+2 种基金External Cooperation Program of Fujian(No.2022I0004)Major Science and Technology Project of Xiamen in China(No.3502Z20191015)Xiamen Natural Science Foundation Youth Project(No.3502Z202471002)。
文摘Quantum dots(QDs),a type of nanoscale semiconductor material with unique optical and electrical properties like adjustable emission and high photoluminescence quantum yields,are suitable for applications in optoelectronics.However,QDs are typically degraded under humid and high-temperature circumstances,greatly limiting their practical value.Coating the QD surface with an inorganic silica layer is a feasible method for improving stability and endurance in a variety of applications.This paper comprehensively reviews silica coating methodologies on QD surfaces and explores their applications in optoelectronic domains.Firstly,the paper provides mainstream silica coating approaches,which can be divided into two categories:in-situ hydrolysis of silylating reagents on QD surfaces and template techniques for encapsulation QDs.Subsequently,the recent applications of the silica-coated QDs on optoelectronic fields including light-emitting diodes,solar cells,photodetectors were discussed.Finally,it reviews recent advances in silica-coated QD technology and prospects for future applications.
基金financial support from the Doctoral Foundation of Henan University of Engineering(No.D2022025)National Natural Science Foundation of China(No.U2004162)+1 种基金National Natural Science Foundation of China(No.52302138)Key Project for Science and Technology Development of Henan Province(No.232102320221)。
文摘With the rapid development of electric vehicles,hybrid electric vehicles and smart grids,people's demand for large-scale energy storage devices is increasingly intense.As a new type of secondary battery,potassium ion battery is promising to replace the lithium-ion battery in the field of large-scale energy storage by virtue of its low price and environmental friendliness.At present,the research on the anode materials of potassium ion batteries mainly focuses on carbon materials and the design of various nanostructured metal-based materials.Problems such as poor rate performance and inferior cycle life caused by electrode structure comminution during charge and discharge have not been solved.Quantum dots/nanodots materials are a new type of nanomaterials that can effectively improve the utilization of electrode materials and reduce production costs.In addition,quantum dots/nanodots materials can enhance the electrode reaction kinetics,reduce the stress generated in cycling,and effectively alleviate the agglomeration and crushing of electrode materials.In this review,we will systematically introduce the synthesis methods,K+storage properties and K+storage mechanisms of carbon quantum dots and carbon-based transition metal compound quantum dots composites.This review will have significant references for potassium ion battery researchers.
基金financial support of National Key Research and Development Program of China(No.2021YFA1501500)the National Natural Science Foundation of China(Nos.22033008,22220102005,22171265)Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(No.2021ZZ103).
文摘The growing environmental concerns regarding rare earth elements in fluorescent powders,along with high production costs,have increased the demand for sustainable alternatives.We propose a promising solution using luminescent metal-organic frameworks(LMOFs)with large surface areas and tunable pore structures,combined with organic carbon quantum dots(CQDs).This study develops a novel white lightemitting diode(WLED)fluorescent powder by incorporating yellow-fluorescent quantum dots(CQDs-Y)into blue-emitting LMOF(ZJU-28),forming the composite material CQDs-Y-n@ZJU-28.The composite exhibits excellent thermal and chemical stability,long-term storage performance,and emits warm white light(CIE:0.3277,0.3281)when subjected to excitation at 365 nm,along with an external quantum efficiency(EQE)of 8.85%.Furthermore,it exhibits tunable emission characteristics and promising LED performance,showcasing a color rendering index(CRI)of 78 and a correlated color temperature of 3384 K.The emitted light undergoes minimal deviation in color towards the white end of the spectrum in the temperature range of 277-437 K,making it an ideal candidate for advanced WLED applications.
基金Supported by National Key Research and Development Program in the 14th five year plan(2021YFA1200700)Strategic Priority Re⁃search Program of the Chinese Academy of Sciences(XDB0580000)Natural Science Foundation of China(62025405,62104235,62105348).
文摘Colloidal quantum dots(CQDs)are affected by the quantum confinement effect,which makes their bandgap tunable.This characteristic allows these materials to cover a broader infrared spectrum,providing a costeffective alternative to traditional infrared detector technology.Recently,thanks to the solution processing properties of quantum dots and their ability to integrate with silicon-based readout circuits on a single chip,infrared detectors based on HgTe CQDs have shown great application prospects.However,facing the challenges of vertically stacked photovoltaic devices,such as barrier layer matching and film non-uniformity,most devices integrated with readout circuits still use a planar structure,which limits the efficiency of light absorption and the effective separation and collection of photo-generated carriers.Here,by synthesizing high-quality HgTe CQDs and precisely controlling the interface quality,we have successfully fabricated a photovoltaic detector based on HgTe and ZnO QDs.At a working temperature of 80 K,this detector achieved a low dark current of 5.23×10^(-9)A cm^(-2),a high rectification ratio,and satisfactory detection sensitivity.This work paves a new way for the vertical integration of HgTe CQDs on silicon-based readout circuits,demonstrating their great potential in the field of high-performance infrared detection.
基金The Tertiary Education Scientific Research Project of the Guangzhou Municipal Education Bureau(2024312227)Innovative and Entrepreneurial Projects of Guangzhou University Students(202411078014)+2 种基金Guangzhou University Open Sharing Fund for Instruments and Equipment(2025)National Major Scientific Research Instrument Development Project(22227804)Sub-subject of the National Key Research Project(2023YFB3210100)。
文摘Calcium ions(Ca^(2+))and manganese ions(Mn^(2+))are essential for sustaining life activities and are key monitoring indicators in drinking water.Developing highly sensitive,selective,and portable detection methods for Ca^(2+)and Mn^(2+)is significant for water quality monitoring and human health.In this paper,blue fluorescent Ti3C2 MXene-based quantum dots(MQDs,λ_(em)=445 nm)are prepared using Ti_(3)C_(2)MXene as the precursor.Through the chelation effect of ethylene diamine tetraacetic acid(EDTA),a blue and red dual-emission fluorescent probe,MQDs-EDTA-Eu^(3+)-DPA,was constructed.Herein,dipicolinic acid(DPA)acts as an absorbing ligand and significantly enhances the red fluorescence of europium ions(Eu^(3+))at 616 nm through the“antenna effect”.The blue fluorescence of MQDs serves as an internal reference signal.High concentrations of Ca^(2+)can quench the red fluorescence of Eu^(3+)-DPA;Mn^(2+)can be excited to emit purple fluorescence at 380 nm after coordinating with DPA,red fluorescence of Eu^(3+)-DPA serves as the internal reference signal.Based on the above two fluorescence intensity changes,ratiometric fluorescence detection methods for Ca^(2+)and Mn^(2+)are established.The fluorescence intensity ratio(IF_(616)/IF_(445))exhibits a linear relationship with Ca^(2+)in the range of 35-120μmol/L,with a detection limit of 5.98μmol/L.The fluorescence intensity ratio(IF_(380)/IF_(616))shows good linearity with Mn^(2+)in the range of 0-14μmol/L,with a detection limit of 28.6 nmol/L.This method was successfully applied to the quantitative analysis of Ca^(2+)and Mn^(2+)in commercially available mineral water(Nongfu Spring,Ganten,and Evergrande),with recovery rates of 80.6%-117%and relative standard deviations(RSD)of 0.76%-4.6%.Additionally,by preparing MQD-based fluorescent test strips,visual detections of Ca^(2+)and Mn^(2+)are achieved.This work demonstrates the application potential of MQDs in the field of visual fluorescence sensing of ions in water quality.
基金X.H.acknowledges the financial support by Australian Research Council(ARC)Future Fellowship(FT190100756)M.P.S.gratefully acknowledges the support by the ARC under Discovery Early Career Researcher Award(DECRA)(DE210101565)and Discovery Project(DP230101676).
文摘The discovery of quantum dots(QDs)stands as one of the paramount technological breakthroughs of the 20th century.Their versatility spans from everyday applications to cutting-edge scientific research,encompassing areas such as displays,lighting,photocatalysis,bio-imaging,and photonics devices and so on.Among the myriad QDs technologies,industrially relevant CuInS_(2)(CIS)QDs have emerged as promising alternatives to traditional Cd-and Pb-based QDs.Their tunable optoelectronic properties,high absorption coefficient,compositional flexibility,remarkable stability as well as Restriction of Hazardous Substances-compliance,with recent trends revealing a renewed interest in this material for various visible and near-infrared technological applications.This review focuses on recent advancements in CIS QDs as multidisciplinary field from its genesis in the mid-1990 to date with an emphasis on key breakthroughs in their synthesis,surface chemistry,post-synthesis modifications,and various applications.First,the comparation of properties of CIS QDs with relevant knowledge from other classes of QDs and from Ⅰ-Ⅱ-Ⅲ semiconductors as well is summarized.Second,recent advances in the synthesis methods,structure-optoelectronic properties,their defects,and passivation strategies as well as CIS-based heterostructures are discussed.Third,the state-of-the-art applications of CIS QDs ranging from solar cells,luminescence solar concentrations,photocatalysis,light emitting diodes,bioimaging and some emerging applications are summarized.Finally,we discuss open challenges and future perspectives for further advancement in this field.
基金supported by the Startup Research-Fund of Henan Academy of Sciences(grant number 241817242)Shenzhen Fundamental Research Scheme-General Program(JCYJ20220818100217037)+2 种基金Key University Laboratory of Highly Efficient Utilization of Solar Energy,Sustainable Development of Guangdong,Southern University of Science and Technology,Shenzhen 518055,China(Y01256331)the National Natural Science Foundation of China(22379017,22179009,U22A2072)supported by the Pico Center at SUSTech CRF which receives support from the Presidential Fund and Development and Reform Commission of Shenzhen Municipality.
文摘Hybrid organic–inorganic lead halide perovskites have emerged as a promising material for high-efficiency solar cells,yet challenges related to crystallization and defects limit their performance and stability.This study investigates the use of perovskite quantum dots(QDs)as crystallization seeds to enhance the quality of FAPbI_(3)perovskite films and improve the performance of perovskite solar cells(PSCs).We demonstrate that CsPbI_(3)and CsPbBr_(3)QDs effectively guide the crystallization process,leading to the formation of larger crystals with preferential orientations,particularly the(001)and(002)planes,which are associated with reduced defect densities.This seedmediated growth strategy resulted in PSCs with power conversion efficiencies(PCEs)of 24.75%and 24.11%,respectively,compared to the baseline efficiency of 22.05%for control devices.Furthermore,devices incorporating QD-treated perovskite films exhibited remarkable stability,maintaining over 80%of their initial PCE after 1000 h of simulated sunlight exposure,a significant improvement over the control.Detailed optoelectronic characterization revealed reduced non-radiative recombination and enhanced charge transport in QD-treated devices.These findings highlight the potential of QDs as a powerful tool to improve perovskite crystallization,facet orientation,and overall device performance,offering a promising route to enhance both efficiency and stability in PSCs.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIT)(no.RS-2022-00165798)。
文摘Metal halide perovskites exhibit excellent absorption properties,high carrier mobility,and remarkable charge transfer ability,showcasing significant potential as light harvesters in new-generation photovoltaic and optoelectronic technologies.Their development has seen unprecedented growth since their discovery.Similar to metal halide perovskite developments,perovskite quantum dots(PQDs)have demonstrated significant versatility in terms of shape,dimension,bandgap,and optical properties,making them suitable for the development of optoelectronic devices.This review discusses various fabrication methods of PQDs,delves into their degradation mechanisms,and explores strategies for enhancing their performance with their applications in a variety of technological fields.Their elevated surface-to-volume ratio highlights their importance in increasing solar cell efficiency.PQDs are also essential for increasing the performance of perovskite solar cells,photodetectors,and lightemitting diodes,which makes them indispensable for solid-state lighting applications.PQDs'unique optoelectronic characteristics make them suitable for sophisticated sensing applications,giving them greater capabilities in this field.Furthermore,PQDs'resistive switching behavior makes them a good fit for applications in memory devices.PQDs'vast potential also encompasses the fields of quantum optics and communication,especially for uses like nanolasers and polarized light detectors.Even though stability and environmental concerns remain major obstacles,research efforts are being made to actively address these issues,enabling PQDs to obtain their full potential in device applications.Simply put,understanding PQDs'real potential lies in overcoming obstacles and utilizing their inherent qualities.
基金supported by the following funding:National Natural Science Foundation of China(Nos.52070057 and 51961165104)Project of a Thousand Youth Talents(No.AUGA2160100917)Open Project of State Key Laboratory of Urban Water Resource and Environment,Harbin Institute of Technology(No.2019DX09)。
文摘Graphene quantum dots(GQDs)are a class of promising carbon-based nanomaterials that have attracted considerable interest from researchers due to their excellent physical,chemical,and biological properties.However,the high cost,toxicity,and laborious preparation process of GQDs also limit their widespread use.To address this issue,the actual research directions consist in replacing traditional non-renewable feedstocks via screening cheap,easily available,and renewable biomass materials based on the concept of resource conservation and environmental friendliness.Herein,the state-of-the-art technologies in the green preparation of GQDs using biomass as carbon source are reported.Initially,the green synthesis strategies as well as the structural,optical,and biosafety properties of GQDs are discussed in detail.Subsequently,the most representative applications of GQDs in energy and environmental remediation fields are summarized.Finally,the current challenges and future potential of the GQDs are presented.