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
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
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
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
We investigate electron mesoscopic transport in a three-terminal setup with coupled quantum dots and a magnetic flux.By mapping the original transport problem into a non-Hermitian Hamiltonian form,we study the interpl...We investigate electron mesoscopic transport in a three-terminal setup with coupled quantum dots and a magnetic flux.By mapping the original transport problem into a non-Hermitian Hamiltonian form,we study the interplay between the coherent couplings between quantum dots,the magnetic flux,and the dissipation due to the tunnel coupling with the reservoirs.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
The crystalline fraction is a critical parameter for assessing the quality of silicon quantum dots(SiQDs),and its enhancement is anticipated to improve the optoelectronic performance of these materials.How-ever,achiev...The crystalline fraction is a critical parameter for assessing the quality of silicon quantum dots(SiQDs),and its enhancement is anticipated to improve the optoelectronic performance of these materials.How-ever,achieving a high crystalline fraction in small-sized SiQDs produced through the pyrolysis of hydro-gen silsesquioxane(HSQ)polymers remains a significant challenge.In this study,we successfully synthe-sized SiQDs with a diameter of 3.24 nm and a crystalline fraction of 98.4%by optimizing the triethoxysi-lane(TES)/aqueous hydrochloric acid(HCl)volume ratio during the hydrolysis-condensation process.The SiQDs exhibited a photoluminescence(PL)center at 764.1 nm and an average PL quantum yield(PLQY)of 24.4%.Our findings demonstrate that the TES/aqueous HCl volume ratio significantly influences the pro-portion of cage structure and the cross-linking density of the network structure in HSQ polymers,which in turn governs SiQD size and crystalline fraction.A high proportion of cage structures in HSQ polymers contributes to high crystallinity.Notably,an increased cross-linking density within the network structure results in higher and more uniform diffusion barriers.This phenomenon not only hinders the diffusion of silicon atoms,which leads to smaller SiQD size,but also facilitates the achievement of high crystalline fraction due to uniform diffusion.This work presents a novel approach to achieving high crystallinity in small SiQDs,with implications for advanced applications in lighting,display technologies,medical imag-ing,and photovoltaics.展开更多
Devising robust S-scheme photocatalysts is of central importance for achieving high-efficient micropollu-tant decontamination.However,the conscious optimization of S-scheme system with high performance remains a prime...Devising robust S-scheme photocatalysts is of central importance for achieving high-efficient micropollu-tant decontamination.However,the conscious optimization of S-scheme system with high performance remains a prime challenge.Herein,carbon quantum dots(CDs)and Mn_(0.5)Cd_(0.5)S(MCS)are mounted on BiOBr(BOB)microspheres,establishing an advanced S-scheme heterojunction with interfacial Bi-S bond.The interfacial Bi-S bonds function as superb channels at atomic-scale to abate the energy barrier for S-scheme charge transportation.Meanwhile,CDs serve as electron collectors to preserve highly reductive electrons from MCS,further augmenting the spatial separation of photo-carriers.Therefore,the optimized CDs/MCS/BOB(MBC)heterojunction manifests significantly strengthened tetracycline hydrochloride(TC)destruction activity and its reaction rate constant is approximately 3.1,2.2,2.1,and 1.5 folds that than that of MCS,BOB,BOB/CDs and MCS/BOB.In addition,MBC exhibits high stability and significant resistance to environmental interferences.The toxicology evaluation confirms the effective abatement of toxicity of TC after treatment.This achievement demonstrates the benefits of CDs-optimized S-scheme photosystems with chemical bonds for photocatalytic water decontamination.展开更多
The photocatalytic hydrogen peroxide(H_(2)O_(2))production by graphitic carbon nitride is a sustainable and environment-benign alternative approach of conventional anthraquinone autoxidation technology,but it is great...The photocatalytic hydrogen peroxide(H_(2)O_(2))production by graphitic carbon nitride is a sustainable and environment-benign alternative approach of conventional anthraquinone autoxidation technology,but it is great challenges to promote two-electron O_(2)reduction and water oxidation.Herein,we present the well-dispersed graphitic carbon nitride quantum dots decorated with cyano groups(Na-CNQD and K-CNQD)by thermal polymerization of melamine in the presence of metal fluoride.The quantum confinement and edge effect have endowed the photocatalysts with rich active sites,wide light absorption range and the inhibited charge recombination.The cyano moieties function as O_(2)reduction centers to accept the photogenerated electrons and facilitate their rapid transfer to O_(2)molecules.This process enables the selective two-electron reduction of O_(2),leading to the production of H_(2)O_(2).Concurrently,the valence band holes on the heptazine moiety oxidize water into H_(2)O_(2).These synergistic effects promote photocatalytic H_(2)O_(2)production from O_(2)and H_(2)O without the need for additional photosensitizers,organic scavengers and co-catalysts.In contrast,pristine carbon nitride nanosheets remain inactive under the same conditions.This study offers new strategies for rational design of carbon-based materials for solar-to-chemical energy conversion.展开更多
Black phosphorus quantum dots(BPQDs)have been used as the nano-carrier in the field of biomedicine due to their excellent electronic conductivity,optical and thermoelectric properties.However,it is still lack of evalu...Black phosphorus quantum dots(BPQDs)have been used as the nano-carrier in the field of biomedicine due to their excellent electronic conductivity,optical and thermoelectric properties.However,it is still lack of evaluation of the safety of BPQDs,specifically on the effects and mechanisms of BPQDs on heart.In this study,the specific pathogen-free male mice were orally administered with different doses of BPQDs(0.02,0.1,0.5 mg/kg)for 28 days.BPQDs exposure decreased the heart-body ratio and caused cardiac hypertrophy and fibrosis.Additionally,ferroptosis was observed in the cardiac tissue.The recent study has shown BPQDs oral exposure alter gut microbiota.Here,after exposure to 0.1 mg/kg BPQDs for 28 days,the germ-free mice showed neither cardiac injury nor ferroptosis.Taken together,the study demonstrates that BPQDs induce cardiac ferroptosis and fibrosis,possibly mediated by gut microbiota.This research may aid in enhancing understanding of the biosafety of BP nanomaterials and promoting the sustainable development of nanotechnology.展开更多
Traditional resistive semiconductor gas sensors suffer from high operating temperatures and poor selectivity.Thus,to address these issues,a highly selective nitrogen dioxide(NO_(2))sensor based on lead sulfide(PbS)qua...Traditional resistive semiconductor gas sensors suffer from high operating temperatures and poor selectivity.Thus,to address these issues,a highly selective nitrogen dioxide(NO_(2))sensor based on lead sulfide(PbS)quantum dots(QDs)–lead molybdate(PbMoO_(4))–molybdenum disulfide(MoS_(2))ternary nanocomposites operating at room temperature was fabricated herein.The ternary nanocomposites were synthesized using an in situ method,yielding Pb S QDs with an average size of~10 nm and PbMoO_(4)nanoparticles in the 10-to 20-nm range,uniformly distributed on ultrathin MoS_(2)nanosheets with an average thickness of~7 nm.The optimized sensor demonstrated a significant improvement in response to 1 ppm NO_(2)at 25℃,achieving a response of 44.5%,which was approximately five times higher than that of the pure MoS_(2)-based sensor(8.5%).The sensor also achieved relatively short response/recovery times and full recovery properties.Notably,the optimal sensor displayed extraordinary selectivity toward NO_(2),showing negligible responses to different interfering gases.Density functional theory(DFT)calculations were conducted to elucidate the underlying sensing mechanism,which was attributed to the enhanced specific surface area,the receptor function of both PbS QDs and PbMoO_(4)nanoparticles,and the transducer function of MoS_(2) nanosheets.展开更多
The endocrine-disrupting chemicals(EDCs)and antibiotics are causing negative effects on human beings and animals by disrupting the endocrine system and spreading antimicrobial resistance.The current need is to eradica...The endocrine-disrupting chemicals(EDCs)and antibiotics are causing negative effects on human beings and animals by disrupting the endocrine system and spreading antimicrobial resistance.The current need is to eradicate pharmaceutical waste from water bodies using advanced catalytic systems with high efficiency.Novel ternary carbon quantum dots(CQDs)decorated Z-Scheme WS_(2)-PANI nanocomposite was prepared by a green synthesis assisted in-situ polymerization for the photodegradation and detection of Estradiol(EST)and Nitrofurantoin(NFT).HRTEM micrographs revealed the formation of CQDs with a mean size of 4nm anchored on the surface of WS_(2)/PANI(width:PANI~20-30nm).The ternary nanocomposite showed excellent photocatalytic activity,degraded NFT(95.7%in 60min),and EST(96.6%in 60min).The rate kinetics study confirms the reaction followed pseudo first-order model.This heterostructure exhibited enhanced performances by modulating the energy level configuration,enhancing the absorption of visible light(2.4eV),and significantly improving the charge separation,three times higher than pristine WS_(2).These are highly favorable for increasing the generation of photoinduced charges and enhancing the overall performance of the catalyst.Further,the electrochemical sensor was prepared using CQDs@WS_(2)/PANI nanocomposite on a paper-based electrode.The CQDs@WS_(2)/PANI exhibit a linear response of 0.1-100nM,with a limit of detection of 13nM.This synergistic interfacial interaction resulted in the significantly improved electrochemical performance of the modified electrode.The proposed Z-scheme was justified by electron paramagnetic resonance(EPR)and scavenger experiment.An intermediate degradation pathway was also proposed.The synthesized materials were characterized using FESEM,HRTEM,XRD,FTIR,XPS,UV-visible spectroscopy,PL,and TRPL.Therefore,this study provides a direct approach to fabricate a heterojunction that combines two-dimensional,one dimensional,and zero-dimensional properties,enabling control over the energy level configuration and subsequent improvements in photocatalytic and electrocatalytic efficiency.展开更多
The authors regret to report some missing information in the synthetic reagents and associated changes of the paper.On page 511,the author information reads:“5.0 mmol of citric acid(C_(6)H_(8)O_(7)),5.0 mmol of ferri...The authors regret to report some missing information in the synthetic reagents and associated changes of the paper.On page 511,the author information reads:“5.0 mmol of citric acid(C_(6)H_(8)O_(7)),5.0 mmol of ferric chloride hexahydrate(FeCl_(3)·6H_(2)O),and 10.0 mmol of o-phenylenediamine(C_(6)H_(8)N_(2))were combined with 40 mL of deionized water and magnetically stirred until fully dissolved.”展开更多
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 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 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.
基金supported by the National Key R&D Program of China(Grant No.2022YFA1404400)the National Natural Science Foundation of China(Grant No.12125504 and 12305050)+2 种基金Zhejiang Provincial Natural Science Foundation of China(Grant No.LZ25A050001)the Hundred Talents Program of the Chinese Academy of Sciencesthe Natural Science Foundation of Jiangsu Higher Education Institutions of China(Grant No.23KJB140017)。
文摘We investigate electron mesoscopic transport in a three-terminal setup with coupled quantum dots and a magnetic flux.By mapping the original transport problem into a non-Hermitian Hamiltonian form,we study the interplay between the coherent couplings between quantum dots,the magnetic flux,and the dissipation due to the tunnel coupling with the reservoirs.
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the Sichuan Science and Technology Program(No.2022ZYD0110)the China National Tobacco Corporation Sichuan Company(No.SCYC202120).
文摘The crystalline fraction is a critical parameter for assessing the quality of silicon quantum dots(SiQDs),and its enhancement is anticipated to improve the optoelectronic performance of these materials.How-ever,achieving a high crystalline fraction in small-sized SiQDs produced through the pyrolysis of hydro-gen silsesquioxane(HSQ)polymers remains a significant challenge.In this study,we successfully synthe-sized SiQDs with a diameter of 3.24 nm and a crystalline fraction of 98.4%by optimizing the triethoxysi-lane(TES)/aqueous hydrochloric acid(HCl)volume ratio during the hydrolysis-condensation process.The SiQDs exhibited a photoluminescence(PL)center at 764.1 nm and an average PL quantum yield(PLQY)of 24.4%.Our findings demonstrate that the TES/aqueous HCl volume ratio significantly influences the pro-portion of cage structure and the cross-linking density of the network structure in HSQ polymers,which in turn governs SiQD size and crystalline fraction.A high proportion of cage structures in HSQ polymers contributes to high crystallinity.Notably,an increased cross-linking density within the network structure results in higher and more uniform diffusion barriers.This phenomenon not only hinders the diffusion of silicon atoms,which leads to smaller SiQD size,but also facilitates the achievement of high crystalline fraction due to uniform diffusion.This work presents a novel approach to achieving high crystallinity in small SiQDs,with implications for advanced applications in lighting,display technologies,medical imag-ing,and photovoltaics.
基金supported by the NSFC-Zhejiang Joint Fund for Integration of Industrialization and Diversification(No.U1809214)the Natural Science Foundation of Zhejiang Province(Nos.LTGN23E080001 and LY20E080014)+1 种基金the Science and Technology Project of Zhoushan(No.2022C41011)the National Natural Science Foundation of China(No.22201251).
文摘Devising robust S-scheme photocatalysts is of central importance for achieving high-efficient micropollu-tant decontamination.However,the conscious optimization of S-scheme system with high performance remains a prime challenge.Herein,carbon quantum dots(CDs)and Mn_(0.5)Cd_(0.5)S(MCS)are mounted on BiOBr(BOB)microspheres,establishing an advanced S-scheme heterojunction with interfacial Bi-S bond.The interfacial Bi-S bonds function as superb channels at atomic-scale to abate the energy barrier for S-scheme charge transportation.Meanwhile,CDs serve as electron collectors to preserve highly reductive electrons from MCS,further augmenting the spatial separation of photo-carriers.Therefore,the optimized CDs/MCS/BOB(MBC)heterojunction manifests significantly strengthened tetracycline hydrochloride(TC)destruction activity and its reaction rate constant is approximately 3.1,2.2,2.1,and 1.5 folds that than that of MCS,BOB,BOB/CDs and MCS/BOB.In addition,MBC exhibits high stability and significant resistance to environmental interferences.The toxicology evaluation confirms the effective abatement of toxicity of TC after treatment.This achievement demonstrates the benefits of CDs-optimized S-scheme photosystems with chemical bonds for photocatalytic water decontamination.
基金supported by the National Natural Science Foundation of China(22361024 and 22471055)Natural Science Foundation of Jiangxi Province(20232ACB203001)+1 种基金Natural Science Foundation of Hebei Province(B2024202021,B2022202039)S&T Program of Hebei(236Z4308G)。
文摘The photocatalytic hydrogen peroxide(H_(2)O_(2))production by graphitic carbon nitride is a sustainable and environment-benign alternative approach of conventional anthraquinone autoxidation technology,but it is great challenges to promote two-electron O_(2)reduction and water oxidation.Herein,we present the well-dispersed graphitic carbon nitride quantum dots decorated with cyano groups(Na-CNQD and K-CNQD)by thermal polymerization of melamine in the presence of metal fluoride.The quantum confinement and edge effect have endowed the photocatalysts with rich active sites,wide light absorption range and the inhibited charge recombination.The cyano moieties function as O_(2)reduction centers to accept the photogenerated electrons and facilitate their rapid transfer to O_(2)molecules.This process enables the selective two-electron reduction of O_(2),leading to the production of H_(2)O_(2).Concurrently,the valence band holes on the heptazine moiety oxidize water into H_(2)O_(2).These synergistic effects promote photocatalytic H_(2)O_(2)production from O_(2)and H_(2)O without the need for additional photosensitizers,organic scavengers and co-catalysts.In contrast,pristine carbon nitride nanosheets remain inactive under the same conditions.This study offers new strategies for rational design of carbon-based materials for solar-to-chemical energy conversion.
基金supported by the National Natural Science Foundation of China(No.22376174)the Natural Science Foundation of Xiamen Municipality(No.2022FCX012503010342).
文摘Black phosphorus quantum dots(BPQDs)have been used as the nano-carrier in the field of biomedicine due to their excellent electronic conductivity,optical and thermoelectric properties.However,it is still lack of evaluation of the safety of BPQDs,specifically on the effects and mechanisms of BPQDs on heart.In this study,the specific pathogen-free male mice were orally administered with different doses of BPQDs(0.02,0.1,0.5 mg/kg)for 28 days.BPQDs exposure decreased the heart-body ratio and caused cardiac hypertrophy and fibrosis.Additionally,ferroptosis was observed in the cardiac tissue.The recent study has shown BPQDs oral exposure alter gut microbiota.Here,after exposure to 0.1 mg/kg BPQDs for 28 days,the germ-free mice showed neither cardiac injury nor ferroptosis.Taken together,the study demonstrates that BPQDs induce cardiac ferroptosis and fibrosis,possibly mediated by gut microbiota.This research may aid in enhancing understanding of the biosafety of BP nanomaterials and promoting the sustainable development of nanotechnology.
基金supported by the National Natural Science Foundation of China(No.52274255)Fundamental Research Funds for the Central Universities,China(Nos.N2401003,N2301003,N2201008,N2201004,and N2301025)+3 种基金Liaoning Revitalization Talents Program,China(No.XLYC2202028)Postdoctoral Foundation of Northeastern University,ChinaYoung Elite Scientists Sponsorship Program by CAST(No.2022QNRC001)China Postdoctoral Science Foundation(No.2022M720025)。
文摘Traditional resistive semiconductor gas sensors suffer from high operating temperatures and poor selectivity.Thus,to address these issues,a highly selective nitrogen dioxide(NO_(2))sensor based on lead sulfide(PbS)quantum dots(QDs)–lead molybdate(PbMoO_(4))–molybdenum disulfide(MoS_(2))ternary nanocomposites operating at room temperature was fabricated herein.The ternary nanocomposites were synthesized using an in situ method,yielding Pb S QDs with an average size of~10 nm and PbMoO_(4)nanoparticles in the 10-to 20-nm range,uniformly distributed on ultrathin MoS_(2)nanosheets with an average thickness of~7 nm.The optimized sensor demonstrated a significant improvement in response to 1 ppm NO_(2)at 25℃,achieving a response of 44.5%,which was approximately five times higher than that of the pure MoS_(2)-based sensor(8.5%).The sensor also achieved relatively short response/recovery times and full recovery properties.Notably,the optimal sensor displayed extraordinary selectivity toward NO_(2),showing negligible responses to different interfering gases.Density functional theory(DFT)calculations were conducted to elucidate the underlying sensing mechanism,which was attributed to the enhanced specific surface area,the receptor function of both PbS QDs and PbMoO_(4)nanoparticles,and the transducer function of MoS_(2) nanosheets.
基金supported by (Dr. Manika Khanuja, Nanomission, (DST)[DST/NM/NB/2018/203(G) (JMI)]UGC grant (No.F.4(201-FRP)/2015 (BSR))
文摘The endocrine-disrupting chemicals(EDCs)and antibiotics are causing negative effects on human beings and animals by disrupting the endocrine system and spreading antimicrobial resistance.The current need is to eradicate pharmaceutical waste from water bodies using advanced catalytic systems with high efficiency.Novel ternary carbon quantum dots(CQDs)decorated Z-Scheme WS_(2)-PANI nanocomposite was prepared by a green synthesis assisted in-situ polymerization for the photodegradation and detection of Estradiol(EST)and Nitrofurantoin(NFT).HRTEM micrographs revealed the formation of CQDs with a mean size of 4nm anchored on the surface of WS_(2)/PANI(width:PANI~20-30nm).The ternary nanocomposite showed excellent photocatalytic activity,degraded NFT(95.7%in 60min),and EST(96.6%in 60min).The rate kinetics study confirms the reaction followed pseudo first-order model.This heterostructure exhibited enhanced performances by modulating the energy level configuration,enhancing the absorption of visible light(2.4eV),and significantly improving the charge separation,three times higher than pristine WS_(2).These are highly favorable for increasing the generation of photoinduced charges and enhancing the overall performance of the catalyst.Further,the electrochemical sensor was prepared using CQDs@WS_(2)/PANI nanocomposite on a paper-based electrode.The CQDs@WS_(2)/PANI exhibit a linear response of 0.1-100nM,with a limit of detection of 13nM.This synergistic interfacial interaction resulted in the significantly improved electrochemical performance of the modified electrode.The proposed Z-scheme was justified by electron paramagnetic resonance(EPR)and scavenger experiment.An intermediate degradation pathway was also proposed.The synthesized materials were characterized using FESEM,HRTEM,XRD,FTIR,XPS,UV-visible spectroscopy,PL,and TRPL.Therefore,this study provides a direct approach to fabricate a heterojunction that combines two-dimensional,one dimensional,and zero-dimensional properties,enabling control over the energy level configuration and subsequent improvements in photocatalytic and electrocatalytic efficiency.
文摘The authors regret to report some missing information in the synthetic reagents and associated changes of the paper.On page 511,the author information reads:“5.0 mmol of citric acid(C_(6)H_(8)O_(7)),5.0 mmol of ferric chloride hexahydrate(FeCl_(3)·6H_(2)O),and 10.0 mmol of o-phenylenediamine(C_(6)H_(8)N_(2))were combined with 40 mL of deionized water and magnetically stirred until fully dissolved.”
