Near-infrared image sensors are widely used in fields such as material identification,machine vision,and autonomous driving.Lead sulfide colloidal quantum dot-based infrared photodiodes can be integrated with sil⁃icon...Near-infrared image sensors are widely used in fields such as material identification,machine vision,and autonomous driving.Lead sulfide colloidal quantum dot-based infrared photodiodes can be integrated with sil⁃icon-based readout circuits in a single step.Based on this,we propose a photodiode based on an n-i-p structure,which removes the buffer layer and further simplifies the manufacturing process of quantum dot image sensors,thus reducing manufacturing costs.Additionally,for the noise complexity in quantum dot image sensors when capturing images,traditional denoising and non-uniformity methods often do not achieve optimal denoising re⁃sults.For the noise and stripe-type non-uniformity commonly encountered in infrared quantum dot detector imag⁃es,a network architecture has been developed that incorporates multiple key modules.This network combines channel attention and spatial attention mechanisms,dynamically adjusting the importance of feature maps to en⁃hance the ability to distinguish between noise and details.Meanwhile,the residual dense feature fusion module further improves the network's ability to process complex image structures through hierarchical feature extraction and fusion.Furthermore,the pyramid pooling module effectively captures information at different scales,improv⁃ing the network's multi-scale feature representation ability.Through the collaborative effect of these modules,the network can better handle various mixed noise and image non-uniformity issues.Experimental results show that it outperforms the traditional U-Net network in denoising and image correction tasks.展开更多
Carbon dot(CD)is an edge-bound,nanometer-sized carbon material possessing unique optical and electronic properties,making it promising metal-free,environmentally benign.In this study,we identified a highly hydrophilic...Carbon dot(CD)is an edge-bound,nanometer-sized carbon material possessing unique optical and electronic properties,making it promising metal-free,environmentally benign.In this study,we identified a highly hydrophilic CD complexed with Fe(Ⅲ)via carboxyl groups to form CD-COOFeⅢ,which exhibited remarkably enhanced Fenton-like reaction performance boosted by visible light irradiation.CD-COOFeⅢenabled high activity in the visible region beyondλ>420 nm,and maintained stable oxidation efficiency in the presence of H_(2)O_(2)over at least ten cycles.The capacity of electrons transferred from photo-excited CD to reduce Fe(Ⅲ)was calculated to be 1.1 mmol/g of CD.Furthermore,the quantum yield(QY)of solarto-Fe(Ⅱ)conversion reached an impressive 87.7%.These findings not only suggest a viable strategy for efficient conversion of solar-to-chemical using a CD-COOFeⅢcomplex in visible light boosted Fenton-like oxidation reaction,but also provide insight for understanding the effect of nanosized artificial and/or natural carbon materials in iron recycling in a natural surface environment.展开更多
The magnetic behavior of a two-electron quantum dot/ring system is analytically studied with electron-electron(e-e)interaction taking into account the Rashba spin-orbit interaction(SOI)and magnetic field.The Jacobi tr...The magnetic behavior of a two-electron quantum dot/ring system is analytically studied with electron-electron(e-e)interaction taking into account the Rashba spin-orbit interaction(SOI)and magnetic field.The Jacobi transformation has been employed to separate the Hamiltonian of the system to the center of mass and relative terms.The Schrödinger equation is analytically solved,and energy spectra are obtained.Then,the magnetization and susceptibility are calculated.The magnetization decreases by raising the magnetic field without and with SOI,and also without e-e interaction.Also,the SOI slightly modifies the magnetization of the system without e-e interaction.The susceptibility displays a peak structure as the magnetic field changes from low values to high values.The susceptibility by considering e-e interaction and without the SOI is always negative and its value decreases by rising the magnetic field.The susceptibility displays a transition from diamagnetic to paramagnetic with e-e interaction and SOI.展开更多
Quantum dot(QD)-based fluorescent inks offer high potential due to their tunable emission and high quantum yield,but their practical application suffers from poor environmental stability,aggregation,and challenges in ...Quantum dot(QD)-based fluorescent inks offer high potential due to their tunable emission and high quantum yield,but their practical application suffers from poor environmental stability,aggregation,and challenges in scalable flexible fabrication.In this study,a high-stability fluorescent ink was developed by incorporating QDs into a polydimethylsiloxane(PDMS)colloidal matrix.High-performance patterned films were then obtained via systematic optimization of screen-printing parameters,with film quality governed by substrate type(131μm PDMS),QD concentration(1.5 mg/mL),and screen mesh count(420 mesh).The optimized films exhibit outstanding environmental and photostability,retaining 75.6% of their fluorescence intensity after immersion in deionized water and 63.8% in 75%ethanol at 25℃ for 100 minutes.Under UV irradiation(365 nm,9 W,100 min),fluorescence intensity decreases by less than 20%.Utilizing their daylight transparency and UV-excitable luminescence,various patterns including QR codes and Code 93 standard barcodes were fabricated via screen printing with high pattern fidelity and machine readability.This study presents a scalable and reliable strategy for the fabrication of flexible,high-stability fluorescent films,supporting their integration into next-generation optoelectronic devices,advanced displays,and secure anti-counterfeiting.展开更多
Herein,antibacterial silver‑doped fluorescent carbon dots(Ag‑CDs)were synthesized through a stepwise hydrothermal method,with polyethyleneimine(PEI),citric acid(CA),and silver nitrate(AgNO3)serving as precursors.The a...Herein,antibacterial silver‑doped fluorescent carbon dots(Ag‑CDs)were synthesized through a stepwise hydrothermal method,with polyethyleneimine(PEI),citric acid(CA),and silver nitrate(AgNO3)serving as precursors.The applicability and antimicrobial efficacy of these nanomaterials were systematically investigated for metal ion sensing.Experimental evidence demonstrated that the Ag‑CDs exhibited a pronounced fluorescence quenching response toward ferric ions(Fe^(3+)),enabling their quantitative determination via a linear concentration‑dependent relationship.These Ag‑CDs exhibited significant inhibitory effects on biofilm growth and disruption for both Escherichia coli and Staphylococcus aureus.Mechanism investigations indicate that Ag‑CDs induced the death of Escherichia coli and Pseudomonas aeruginosa by disrupting their bacterial morphology and structure,triggering the generation of intracellular reactive oxygen species(ROS),and impairing their antioxidant defense system.展开更多
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
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
Carbon dots(CDs),a class of emerging fluorescent nanomaterials,have garnered notable attention in the biomedical field owing to their outstanding photoluminescence properties,excellent biocompatibility,and ease of syn...Carbon dots(CDs),a class of emerging fluorescent nanomaterials,have garnered notable attention in the biomedical field owing to their outstanding photoluminescence properties,excellent biocompatibility,and ease of synthesis and functionalization.Recently,numerous CDs have been developed that allow precise subcellular localization through surface modifications or covalent conjugation with targeting ligands such as peptides,small molecules,Golgi-specific agents,and cell membrane-specific agents.This review begins with an overview of the synthesis strategies of CDs,highlighting their exceptional optical properties,stability,biocompatibility,and significance for subcellular imaging.The mechanisms by which CDs target specific organelles,including the nucleus,mitochondrion,lysosomes,Golgi apparatus,and cell membrane,are discussed.These mechanisms include specific targeting molecules,pH-sensitive targeting,charge-driven interactions,and hydrophobic and hydrophilic dynamics.Furthermore,we summarize their applications in subcellular imaging,such as the long-term dynamic monitoring of organelles,sensing,reactive oxygen species scavenging,and therapy.By presenting a comprehensive review of CDs in subcellular imaging,we aim to pave the way for further development of CDs in bioimaging and related biomedical 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
Portable ratiometric fluorescent platforms have emerged as promising tools for multifarious detection,yet remain unexplored for point-of-care monitoring doxorubicin(DOX),one of clinically antineoplastic drugs.To this ...Portable ratiometric fluorescent platforms have emerged as promising tools for multifarious detection,yet remain unexplored for point-of-care monitoring doxorubicin(DOX),one of clinically antineoplastic drugs.To this end,we herein develop a portable self-calibrating platform namely carbon dots(C-dots)-embedded hydrogel sensors with a smartphone-assisted high-throughput imaging device,for DOX sensing.The prepared green-emitting(λ_(em)=508 nm)and negatively-charged C-dots(−11.40±1.21 mV),which have sufficient spectral overlap with the absorption band of DOX(∼500 nm),can strongly bind with positively-charged DOX molecules by electrostatic attraction effects.As a result,DOX molecules are selectively and rapid(20 s)determined with a detection limit of 10.26 nmol/L via Förster resonance energy transfer processes,demonstrating a remarkably chromatic shift from green to red.Further integrated with a 3D-printed smartphone-assisted device,the platform enabled high-throughput quantification,achieving recoveries of 96.40%-101.85%in human urine/serum(RSDs<2.94%,n=3).Notably,the dual linear detection ranges of the platform align with the reported clinical DOX concentrations in urine and plasma(0-4 h post-administration),validating their capability for direct quantification of DOX in clinical samples without special pre-treatment processes.By virtue of attractive analytical performances and robust feasibility,this platform bridges laboratory precision and point-of-care testing needs,offering promising potential for personalized chemotherapy and multiplexed analyte screening.展开更多
Photocatalytic fuel cells provide promising opportunities for sustainable wastewater treatment and energy conversion.However,their applications are challenged by the sluggish oxygen reducton reaction(ORR)kinetics at c...Photocatalytic fuel cells provide promising opportunities for sustainable wastewater treatment and energy conversion.However,their applications are challenged by the sluggish oxygen reducton reaction(ORR)kinetics at cathodes owning to the low O_(2) solubility and diffusion rate.Herein,we proposed a photobiocatalytic fuel cell(PBFC) with a novel hybrid biocathode based on artificially engineered algal cells coated by ZIF-8 confined carbon dots/bilirubin oxidase(ZIF-8/CDs/BOD@algae).Microalgae absorbed CO_(2) and provided O_(2) in situ for BOD catalysts.Due to effective absorption of O_(2) by imidazole and confinement of hydrophobic porous ZIF-8,oxygen diffusion has been accelerated in MOF/enzyme systems.Importantly,the introduction of CDs alleviated the poor conductivity of ZIF-8 and improved the electron transfer rate of BOD.Thus,the biocathode exhibited a high current density of 1767 μA/cm^(2),a 2.26-fold increase compared with that of CDs/BOD/algae biocathode.Also,it displayed enduring operational stability for up to 60 h since the firmly wrapped ZIF-8 shells could encapsulate proteins and protect algae from the external stimulation.When coupled with Mo:BiVO_(4) photoanodes,the PBFC exhibited a remarkable power output of 131.8 μW/cm^(2) using tetracycline hydrochloride(TCH) as a fuel and an increased degradation rate of TCH.Therefore,this work not only establishs an effective confinement strategy for enzyme to enrich oxygen,but also unveils new possibilities for modified microalgal cells aiding photoelectrocatalytic systems to recover energy from wastewater treatment.展开更多
Designing efficient,stable dual-functional combustion catalysts remains a key challenge in developing next-generation solid propellants,particularly in achieving wide pressure plateau combustion.Herein,we synthesize a...Designing efficient,stable dual-functional combustion catalysts remains a key challenge in developing next-generation solid propellants,particularly in achieving wide pressure plateau combustion.Herein,we synthesize a series of carbon dot-based catalysts(CDs-1,CDs-2,CDs/Cu)via oxidative etching and hydrothermal methods,and employ them to replace conventional carbon black(CB)at 0.65 wt%loading in the preparation of HMX-CMDB propellants.Systematic evaluation through combined thermochemical analysis(50–350℃),laser ignition diagnostics(50–350 W/cm^(2)),and combustion chamber testing(4–18 MPa)reveals remarkable catalytic enhancements.The optimized CDs/Cu catalyst demonstrates multifunctional superiority:(1)7.4℃ reduction in HMX-CMDB decomposition temperature at 10℃/min(from 205.2℃ to 196.0℃);(2)66.7%decrease in laser ignition delay(from 45 ms to 15 ms);(3)190.9%burning rate increase at 4 MPa(from 4.61 mm/s to 13.41 mm/s);(4)lower pressure exponent of 0.02 within 4–18 MPa range.Notably,CDs-1 induces stable"Plateau"combustion(4–14 MPa),while CDs/Cu achieves"Mesa"effects(8–12 MPa)via synergistic thermal feedback mechanisms-both phenomena ensure stable operation of the engine.Mechanistic studies integrate thermochemical kinetics,ignition combustion process,combustion flame structure,and combustion wave temperature distribution trends,which establish a new paradigm for the study of high efficiency combustion catalysts for solid propellants.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 dot systems emerge as promising platforms for studying nanoscale thermoelectric effects and quantum fluctuation phenomena.In this work,we investigate the thermodynamic performance of a Coulomb-blockaded quantu...Quantum dot systems emerge as promising platforms for studying nanoscale thermoelectric effects and quantum fluctuation phenomena.In this work,we investigate the thermodynamic performance of a Coulomb-blockaded quantum dot operating as a quantum heat engine using the quantum master equation approach.By incorporating full counting statistics,we analyze both average transport properties and current fluctuations in this nanoscale system.We demonstrate that electron-electron interactions significantly enhance thermoelectric performance by increasing both the output power and energy conversion efficiency.Furthermore,we show that Coulomb interactions suppress current fluctuations while preserving the validity of the thermodynamic uncertainty relation.Our results provide important insights into the interplay between quantum effects and thermodynamic principles in nanoscale heat engines.展开更多
基金Supported by the National key research and development program in the 14th five year plan 2021YFA1200700)the National Natural Science Foundation of China(62535018,62431025,62561160113)the Natural Science Foundation of Shanghai(23ZR1473400).
文摘Near-infrared image sensors are widely used in fields such as material identification,machine vision,and autonomous driving.Lead sulfide colloidal quantum dot-based infrared photodiodes can be integrated with sil⁃icon-based readout circuits in a single step.Based on this,we propose a photodiode based on an n-i-p structure,which removes the buffer layer and further simplifies the manufacturing process of quantum dot image sensors,thus reducing manufacturing costs.Additionally,for the noise complexity in quantum dot image sensors when capturing images,traditional denoising and non-uniformity methods often do not achieve optimal denoising re⁃sults.For the noise and stripe-type non-uniformity commonly encountered in infrared quantum dot detector imag⁃es,a network architecture has been developed that incorporates multiple key modules.This network combines channel attention and spatial attention mechanisms,dynamically adjusting the importance of feature maps to en⁃hance the ability to distinguish between noise and details.Meanwhile,the residual dense feature fusion module further improves the network's ability to process complex image structures through hierarchical feature extraction and fusion.Furthermore,the pyramid pooling module effectively captures information at different scales,improv⁃ing the network's multi-scale feature representation ability.Through the collaborative effect of these modules,the network can better handle various mixed noise and image non-uniformity issues.Experimental results show that it outperforms the traditional U-Net network in denoising and image correction tasks.
基金the support of Natural Science Foundation of China(No.22276123)the Shanghai Engineering Research Center of Water Environment Simulation and Ecological Restoration(No.WESER-202201)the Postdoctoral Fellowship Program of CPSF(No.GZB20240456)。
文摘Carbon dot(CD)is an edge-bound,nanometer-sized carbon material possessing unique optical and electronic properties,making it promising metal-free,environmentally benign.In this study,we identified a highly hydrophilic CD complexed with Fe(Ⅲ)via carboxyl groups to form CD-COOFeⅢ,which exhibited remarkably enhanced Fenton-like reaction performance boosted by visible light irradiation.CD-COOFeⅢenabled high activity in the visible region beyondλ>420 nm,and maintained stable oxidation efficiency in the presence of H_(2)O_(2)over at least ten cycles.The capacity of electrons transferred from photo-excited CD to reduce Fe(Ⅲ)was calculated to be 1.1 mmol/g of CD.Furthermore,the quantum yield(QY)of solarto-Fe(Ⅱ)conversion reached an impressive 87.7%.These findings not only suggest a viable strategy for efficient conversion of solar-to-chemical using a CD-COOFeⅢcomplex in visible light boosted Fenton-like oxidation reaction,but also provide insight for understanding the effect of nanosized artificial and/or natural carbon materials in iron recycling in a natural surface environment.
文摘The magnetic behavior of a two-electron quantum dot/ring system is analytically studied with electron-electron(e-e)interaction taking into account the Rashba spin-orbit interaction(SOI)and magnetic field.The Jacobi transformation has been employed to separate the Hamiltonian of the system to the center of mass and relative terms.The Schrödinger equation is analytically solved,and energy spectra are obtained.Then,the magnetization and susceptibility are calculated.The magnetization decreases by raising the magnetic field without and with SOI,and also without e-e interaction.Also,the SOI slightly modifies the magnetization of the system without e-e interaction.The susceptibility displays a peak structure as the magnetic field changes from low values to high values.The susceptibility by considering e-e interaction and without the SOI is always negative and its value decreases by rising the magnetic field.The susceptibility displays a transition from diamagnetic to paramagnetic with e-e interaction and SOI.
文摘Quantum dot(QD)-based fluorescent inks offer high potential due to their tunable emission and high quantum yield,but their practical application suffers from poor environmental stability,aggregation,and challenges in scalable flexible fabrication.In this study,a high-stability fluorescent ink was developed by incorporating QDs into a polydimethylsiloxane(PDMS)colloidal matrix.High-performance patterned films were then obtained via systematic optimization of screen-printing parameters,with film quality governed by substrate type(131μm PDMS),QD concentration(1.5 mg/mL),and screen mesh count(420 mesh).The optimized films exhibit outstanding environmental and photostability,retaining 75.6% of their fluorescence intensity after immersion in deionized water and 63.8% in 75%ethanol at 25℃ for 100 minutes.Under UV irradiation(365 nm,9 W,100 min),fluorescence intensity decreases by less than 20%.Utilizing their daylight transparency and UV-excitable luminescence,various patterns including QR codes and Code 93 standard barcodes were fabricated via screen printing with high pattern fidelity and machine readability.This study presents a scalable and reliable strategy for the fabrication of flexible,high-stability fluorescent films,supporting their integration into next-generation optoelectronic devices,advanced displays,and secure anti-counterfeiting.
文摘Herein,antibacterial silver‑doped fluorescent carbon dots(Ag‑CDs)were synthesized through a stepwise hydrothermal method,with polyethyleneimine(PEI),citric acid(CA),and silver nitrate(AgNO3)serving as precursors.The applicability and antimicrobial efficacy of these nanomaterials were systematically investigated for metal ion sensing.Experimental evidence demonstrated that the Ag‑CDs exhibited a pronounced fluorescence quenching response toward ferric ions(Fe^(3+)),enabling their quantitative determination via a linear concentration‑dependent relationship.These Ag‑CDs exhibited significant inhibitory effects on biofilm growth and disruption for both Escherichia coli and Staphylococcus aureus.Mechanism investigations indicate that Ag‑CDs induced the death of Escherichia coli and Pseudomonas aeruginosa by disrupting their bacterial morphology and structure,triggering the generation of intracellular reactive oxygen species(ROS),and impairing their antioxidant defense system.
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.
基金support received from the National Natural Science Foundation of China(No.U24A2079).
文摘Carbon dots(CDs),a class of emerging fluorescent nanomaterials,have garnered notable attention in the biomedical field owing to their outstanding photoluminescence properties,excellent biocompatibility,and ease of synthesis and functionalization.Recently,numerous CDs have been developed that allow precise subcellular localization through surface modifications or covalent conjugation with targeting ligands such as peptides,small molecules,Golgi-specific agents,and cell membrane-specific agents.This review begins with an overview of the synthesis strategies of CDs,highlighting their exceptional optical properties,stability,biocompatibility,and significance for subcellular imaging.The mechanisms by which CDs target specific organelles,including the nucleus,mitochondrion,lysosomes,Golgi apparatus,and cell membrane,are discussed.These mechanisms include specific targeting molecules,pH-sensitive targeting,charge-driven interactions,and hydrophobic and hydrophilic dynamics.Furthermore,we summarize their applications in subcellular imaging,such as the long-term dynamic monitoring of organelles,sensing,reactive oxygen species scavenging,and therapy.By presenting a comprehensive review of CDs in subcellular imaging,we aim to pave the way for further development of CDs in bioimaging and related biomedical 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 the National NaturalScience Foundation of China(No.22274001)the Key Project of Natural Science Research of the Education Department of Anhui Province(No.2022AH051032)the Excellent Research and Innovation Team of Universities in Anhui Province(No.2024AH010016).
文摘Portable ratiometric fluorescent platforms have emerged as promising tools for multifarious detection,yet remain unexplored for point-of-care monitoring doxorubicin(DOX),one of clinically antineoplastic drugs.To this end,we herein develop a portable self-calibrating platform namely carbon dots(C-dots)-embedded hydrogel sensors with a smartphone-assisted high-throughput imaging device,for DOX sensing.The prepared green-emitting(λ_(em)=508 nm)and negatively-charged C-dots(−11.40±1.21 mV),which have sufficient spectral overlap with the absorption band of DOX(∼500 nm),can strongly bind with positively-charged DOX molecules by electrostatic attraction effects.As a result,DOX molecules are selectively and rapid(20 s)determined with a detection limit of 10.26 nmol/L via Förster resonance energy transfer processes,demonstrating a remarkably chromatic shift from green to red.Further integrated with a 3D-printed smartphone-assisted device,the platform enabled high-throughput quantification,achieving recoveries of 96.40%-101.85%in human urine/serum(RSDs<2.94%,n=3).Notably,the dual linear detection ranges of the platform align with the reported clinical DOX concentrations in urine and plasma(0-4 h post-administration),validating their capability for direct quantification of DOX in clinical samples without special pre-treatment processes.By virtue of attractive analytical performances and robust feasibility,this platform bridges laboratory precision and point-of-care testing needs,offering promising potential for personalized chemotherapy and multiplexed analyte screening.
基金support from National Natural Science Foundation of China (Nos.22176086,52100014)Natural Science Foundation of Jiangsu Province (No.BK20210189)+7 种基金State Key laboratory of Pollution Control and Resource Reuse,the Fundamental Research Funds for the Central Universities (Nos.021114380183,021114380189,021114380199)the Research Funds from Frontiers Science Center for Critical Earth Material Cycling of Nanjing UniversityResearch Funds for Jiangsu Distinguished ProfessorCarbon Peaking and Carbon Neutrality Technological Innovation Foundation of Jiangsu Province (No.BE2022861)the Central Universities - Cemac “Geo X” Interdisciplinary Program (No.021114380217)Frontiers Science Center for Critical Earth Material Cycling of Nanjing University (No.2024QNXZ07)Postdoctoral Fellowship Program of CPSF (No.GZC20231105)the Jiangsu Funding Program for Excellent Postdoctoral Talent (No.2023ZB226)。
文摘Photocatalytic fuel cells provide promising opportunities for sustainable wastewater treatment and energy conversion.However,their applications are challenged by the sluggish oxygen reducton reaction(ORR)kinetics at cathodes owning to the low O_(2) solubility and diffusion rate.Herein,we proposed a photobiocatalytic fuel cell(PBFC) with a novel hybrid biocathode based on artificially engineered algal cells coated by ZIF-8 confined carbon dots/bilirubin oxidase(ZIF-8/CDs/BOD@algae).Microalgae absorbed CO_(2) and provided O_(2) in situ for BOD catalysts.Due to effective absorption of O_(2) by imidazole and confinement of hydrophobic porous ZIF-8,oxygen diffusion has been accelerated in MOF/enzyme systems.Importantly,the introduction of CDs alleviated the poor conductivity of ZIF-8 and improved the electron transfer rate of BOD.Thus,the biocathode exhibited a high current density of 1767 μA/cm^(2),a 2.26-fold increase compared with that of CDs/BOD/algae biocathode.Also,it displayed enduring operational stability for up to 60 h since the firmly wrapped ZIF-8 shells could encapsulate proteins and protect algae from the external stimulation.When coupled with Mo:BiVO_(4) photoanodes,the PBFC exhibited a remarkable power output of 131.8 μW/cm^(2) using tetracycline hydrochloride(TCH) as a fuel and an increased degradation rate of TCH.Therefore,this work not only establishs an effective confinement strategy for enzyme to enrich oxygen,but also unveils new possibilities for modified microalgal cells aiding photoelectrocatalytic systems to recover energy from wastewater treatment.
基金supported by the National Natural Science Foundation of China(Grant No.22205178).
文摘Designing efficient,stable dual-functional combustion catalysts remains a key challenge in developing next-generation solid propellants,particularly in achieving wide pressure plateau combustion.Herein,we synthesize a series of carbon dot-based catalysts(CDs-1,CDs-2,CDs/Cu)via oxidative etching and hydrothermal methods,and employ them to replace conventional carbon black(CB)at 0.65 wt%loading in the preparation of HMX-CMDB propellants.Systematic evaluation through combined thermochemical analysis(50–350℃),laser ignition diagnostics(50–350 W/cm^(2)),and combustion chamber testing(4–18 MPa)reveals remarkable catalytic enhancements.The optimized CDs/Cu catalyst demonstrates multifunctional superiority:(1)7.4℃ reduction in HMX-CMDB decomposition temperature at 10℃/min(from 205.2℃ to 196.0℃);(2)66.7%decrease in laser ignition delay(from 45 ms to 15 ms);(3)190.9%burning rate increase at 4 MPa(from 4.61 mm/s to 13.41 mm/s);(4)lower pressure exponent of 0.02 within 4–18 MPa range.Notably,CDs-1 induces stable"Plateau"combustion(4–14 MPa),while CDs/Cu achieves"Mesa"effects(8–12 MPa)via synergistic thermal feedback mechanisms-both phenomena ensure stable operation of the engine.Mechanistic studies integrate thermochemical kinetics,ignition combustion process,combustion flame structure,and combustion wave temperature distribution trends,which establish a new paradigm for the study of high efficiency combustion catalysts for solid propellants.
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 National Natural Science Foundation of China(Grant No.12305050)the Natural Science Foundation of Jiangsu Higher Education Institutions of China(Grant No.23KJB140017)the Zhejiang Provincial Natural Science Foundation of China(Grant No.LZ25A050001)。
文摘Quantum dot systems emerge as promising platforms for studying nanoscale thermoelectric effects and quantum fluctuation phenomena.In this work,we investigate the thermodynamic performance of a Coulomb-blockaded quantum dot operating as a quantum heat engine using the quantum master equation approach.By incorporating full counting statistics,we analyze both average transport properties and current fluctuations in this nanoscale system.We demonstrate that electron-electron interactions significantly enhance thermoelectric performance by increasing both the output power and energy conversion efficiency.Furthermore,we show that Coulomb interactions suppress current fluctuations while preserving the validity of the thermodynamic uncertainty relation.Our results provide important insights into the interplay between quantum effects and thermodynamic principles in nanoscale heat engines.
