In this work,we synthesize two luminescent Pt(Ⅱ)complexes using differentπ-conjugated bidentate ligands.Both complexes are assembled into three-dimensional(3D)networks through non-classical intermolecular interactio...In this work,we synthesize two luminescent Pt(Ⅱ)complexes using differentπ-conjugated bidentate ligands.Both complexes are assembled into three-dimensional(3D)networks through non-classical intermolecular interactions in the crystal state.Unexpectedly,substituting pyridine with the more extensivelyπ-conjugated quinoline significantly increases the dihedral angles between the phenyl and quinolyl groups of the bidentate ligands.This alteration disrupts theπ-πinteractions between molecules,resulting in distinct optical properties upon exposure to external stimuli.By integrating these complexes into polymers,we fabricate electrospun films containing luminescent nanofibers that exhibit reversible optical changes.These findings have paved the way for the development of high-performance optical encryption and anti-counterfeiting materials,achieved through the employment of simple chromophores.展开更多
The application of aggregation-induced emission(AIE)materials in biological imaging holds multiple significances,including improving detection sensitivity and specificity,optimizing the imaging process,expanding the s...The application of aggregation-induced emission(AIE)materials in biological imaging holds multiple significances,including improving detection sensitivity and specificity,optimizing the imaging process,expanding the scope of application,and promoting advancements in biomedical research.In this work,the propeller ligand was constructed through McMurry coupling reaction and Suzuki coupling reaction by using dimethoxybenzophenone as the starting material.Then,an imine condensation reaction was carried out in chloroform solution,using a 3:2 molar ratio of precursor to tri(2-aminoethyl)amine to synthesize C3 symmetric porous organic cage CB.The structures of the compounds were determined by nuclear magnetic resonance spectroscopy(NMR),electrospray ionization mass spectrometry(ESI-MS)and Fourier transform infrared spectroscopy(FT-IR).The optical investigation results reveal that ligand L-B and the porous organic cage C_(B) demonstrate remarkable aggregation-induced emission(AIE)properties in a tetrahydrofuran/water mixed solvent system,along with a pronounced response to tetrahydrofuran vapor stimuli.Consequently,Furthermore,given its unique cage-like structure,high quantum yield,and outstanding AIE behavior,the porous organic cage C_(B) holds promise for applications in cell imaging.展开更多
Er^(3+)-and Tm^(3+)-doped Ca_(x)Sr_(2-x)Nb_(2)O_(7)(C_(x)S_(2-x)N,x=0.6,0.8,1,0,1.2,1,4) phosphors with layered pe rovskite structure were designed.These phosphors exhibit a dominant emission peak at 549 nm under980 n...Er^(3+)-and Tm^(3+)-doped Ca_(x)Sr_(2-x)Nb_(2)O_(7)(C_(x)S_(2-x)N,x=0.6,0.8,1,0,1.2,1,4) phosphors with layered pe rovskite structure were designed.These phosphors exhibit a dominant emission peak at 549 nm under980 nm laser excitation,attributed to the^(4)S_(3/2)→^(4)I_(15/2)transition.By increasing the content of Ca^(2+),the crystal field regulation of rare earth ions is realized and the luminescence enhancement is induced,which is manifested by the increase of^(2)H_(11/2),^(4)S_(3/2)→^(4)I_(15/2)emission.Furthermore,the temperature sensing sensitivities of C_(0.6)S_(1.4)N:Er,Tm and C_(0.6)S_(1.4)N:Er,Tm based on non-thermally coupled energy levels were studied.Finally,an anti-counterfeiting imprint was prepared using phosphors,which have high brightness and excellent photothermal stability.This work not only confirms that closer ionic radii substitution enables to increase the electronic density of states,improve the crystal field symmetry and enhance the luminescence,but also provides a promising phosphor system for temperature sensing and anti-counterfeiting applications,opening up new prospects in the optimization of the optical properties of phosphors.展开更多
Counterfeiting is still a pervasive global issue,affecting multiple industries and hindering industrial innovation,while causing substantial financial losses,reputational damage,and risks to consumer safety.From luxur...Counterfeiting is still a pervasive global issue,affecting multiple industries and hindering industrial innovation,while causing substantial financial losses,reputational damage,and risks to consumer safety.From luxury goods and pharmaceuticals to electronics and automotive parts,counterfeit products infiltrate supply chains,leading to a loss of revenue for legitimate businesses and undermining consumer trust.Traditional anti-counterfeiting measures,such as holograms,serial numbers,and barcodes,have proven to be insufficient as counterfeiters continuously develop more sophisticated replication techniques.As a result,there is a growing need for more advanced,secure,and reliable methods to prevent counterfeiting.This paper presents a novel,holistic anti-counterfeiting platform that integrates Near Field Communication(NFC)-enabled mobile applications with blockchain technology to provide an innovative,secure,and consumer-friendly authentication mechanism.Our approach addresses key gaps in existing solutions by incorporating dynamic product identifiers,which make replication significantly more difficult.The system enables consumers to verify the authenticity of products instantly using their smartphones,enhancing transparency and trust in the supply chain.Blockchain technology plays a crucial role in our proposed solution by providing an immutable,decentralized ledger that records product authentication data.This ensures that product verification records cannot be tampered with or altered,adding a layer of security that is absent in conventional systems.Additionally,NFC technology enhances security by offering unique identification capabilities,enabling real-time product verification.To validate the effectiveness of the proposed system,real-world testing was conducted across different industries.The results demonstrated the platform’s ability to significantly reduce counterfeit products in the supply chain,offering businesses and consumers a more robust and reliable authentication method.By leveraging the combined strengths of blockchain and NFC,this solution represents a significant advancement in the fight against counterfeiting,ensuring enhanced security,transparency,and consumer trust.展开更多
Stimulus-responsive room-temperature phosphorescence(RTP)materials have gained significant attention for their important optoelectronic application prospects.However,the fabrication strategy and underlying mechanism o...Stimulus-responsive room-temperature phosphorescence(RTP)materials have gained significant attention for their important optoelectronic application prospects.However,the fabrication strategy and underlying mechanism of stimulus-responsive RTP materials remain less explored.Herein,we present a reliable strategy for achieving pH-responsive RTP materials by integrating poly(vinyl alcohol)(PVA)with carboxylic acid or amino group functionalized terpyridine(Tpy)derivatives.The resulting Tpy derivativesbased RTP materials displayed reversible changes in emission color,intensity,and lifetime of both prompt and delayed emission.Notably,the RTP emission undergoes a significant diminish upon exposure to acid due to the protonation of Tpy units.Taking advantage of the decent RTP emission and pH-responsiveness of these RTP films,a spatial-time-resolved anti-counterfeiting application is demonstrated as a proof-ofconcept for largely enhancing the security level.This study not only provides new prospects for developing smart RTP materials but also promotes the advancement of optical anti-counterfeiting applications.展开更多
Counterfeiting of modern banknotes poses a significant challenge,prompting the use of various preventive measures.One such measure is the magnetic anti-counterfeiting strip.However,due to its inherent weak magnetic pr...Counterfeiting of modern banknotes poses a significant challenge,prompting the use of various preventive measures.One such measure is the magnetic anti-counterfeiting strip.However,due to its inherent weak magnetic properties,visualizing its magnetic distribution has been a longstanding challenge.In this work,we introduce an innovative method by using a fiber optic diamond probe,a highly sensitive quantum sensor designed specifically for detecting extremely weak magnetic fields.We employ this probe to achieve high-resolution imaging of the magnetic fields associated with the RMB 50denomination anti-counterfeiting strip.Additionally,we conduct computer simulations by using COMSOL Multiphysics software to deduce the potential geometric characteristics and material composition of the magnetic region within the anti-counterfeiting strip.The findings and method presented in this study hold broader significance,extending the RMB 50 denomination to various denominations of the Chinese currency and other items that employ magnetic anti-counterfeiting strips.These advances have the potential to significantly improve and promote security measures in order to prevent the banknotes from being counterfeited.展开更多
In this study,the hexagonal NaYF_(4):Yb^(3+)/Ho^(3+)/Ce^(3+) microcrystals were synthesized controllably,and upconversion luminescence excited at 940 nm and its application in temperature-responsive anti-counterfeitin...In this study,the hexagonal NaYF_(4):Yb^(3+)/Ho^(3+)/Ce^(3+) microcrystals were synthesized controllably,and upconversion luminescence excited at 940 nm and its application in temperature-responsive anti-counterfeiting are reported.It is clarified that the Ln^(3+)(Ln=Y+Yb+Ho+Ce)density ratio of bottom plane to side plane in the unit cell can be regulated by Ce^(3+) doping.It is also proved that the energy transfer of Yb^(3+) to Ho^(3+) is responsible for the activation of Ho^(3+)under 940 nm excitation,while the cross relaxation between Ho^(3+)and Ce^(3+)participates in the redistribution of electron population of^(5)S_(2)/^(5)F_(4)and^(5)F_(5)levels.Both theory and experiment confirm that the intensity ratio of red to green emission(I_(R)/I_(G))as a function of temperature as an independent variable has good linear characteristics in the temperature range of 300-500 K.Due to the good responsiveness of multicolor luminescence to temperature,the hexagonal NaYF_(4):Yb^(3+)/Ho^(3+)/Ce^(3+) with tunable morphology is a promising candidate for advanced temperature-responsive upconversion anti-counterfeiting.Our results provide a new pathway for the controllable synthesis of hexagonal NaYF_(4)microcrystals as well as the regulation of upconversion luminescence that is excited by wavelengths other than 980 nm and its application in anti-counterfeiting.展开更多
A benzoic acid rare earth(Tb) complex was synthesized and characterized.The excitation and emission spectra of the complex were investigated,and then pure organic complex was incorporated with inorganic matrices(SiO2)...A benzoic acid rare earth(Tb) complex was synthesized and characterized.The excitation and emission spectra of the complex were investigated,and then pure organic complex was incorporated with inorganic matrices(SiO2) through sol-gel method.The composition and structure of the hybrid complex was characterized through the IR spectra,TG,TEM and fluorescent spectrometer.Furthermore,the polypropylene(PP) fluorescent fiber with the organic-inorganic hybrid was prepared by melt spinning.The fluorescent and mechanical properties of the fiber were also tested.The results showed that after sol-gel coating the average particulate dimension of the hybrid rare earth complex was less than 100 nm and thermal stability was improved.Meanwhile,the fiber possessed excellent fluorescent and mechanical properties,which could be used as a candidate applied to excellent fluorescent anti-counterfeiting fiber.展开更多
Carbon dots(CDs) with fluorescence(FL) and room-temperature phosphorescence(RTP) optical properties have attracted dramatically growing interest in anti-counterfeiting application. Herein, color-tunable and stable FL ...Carbon dots(CDs) with fluorescence(FL) and room-temperature phosphorescence(RTP) optical properties have attracted dramatically growing interest in anti-counterfeiting application. Herein, color-tunable and stable FL and ultralong RTP(to naked eyes ~14 s) are successfully achieved in CDs system. Encoding information and patterns fabricated by directly screen-printing method are invisible to eyes under natural light. Interestingly, clear and multicolor patterns with tunable FL and RTP emissions are identified under the 365 nm, 395 nm and 465 nm excitation and removal of them, indicating potential application of carbon dots with different FL and RTP outputs in the high-level photonic anti-counterfeiting field.展开更多
Anti-counterfeiting labels with various fluorescent colors are of great importance in information encryption-decryption,but are still limited to static information display.Therefore,it is urgent to develop new materia...Anti-counterfeiting labels with various fluorescent colors are of great importance in information encryption-decryption,but are still limited to static information display.Therefore,it is urgent to develop new materials and encryption-decryption logic for improving the security level of secret information.In this study,an organohydrogel made up of poly(N,N-dimethylacrylamide)(pDMA)hydrogel network and polyoctadecyl methacrylate(pSMA)organogel network that copolymerized with two fluorophores,6-acrylamidopicolinic acid moieties(6APA,fluorescent ligand)and spiropyran units(SPMA,photochromic monomer),was prepared by a two-step interpenetrating method.As UV light of 365nm and 254nm can both cleave C_(spiro)-O bonds of SPMA,and the green fluorescence of 6APA-Tb^(3+) can only be excited by 254nm light,the organohydrogel displays yellow and red under the irradiation of 254nm and 365 nm,respectively.In addition to wavelength selectivity,these two fluorophores are thermal-responsive,leading to the fluorescence variation of the organohydrogel during heating process.As a result,secret information loaded on the organohydrogel can be decrypted by the irradiation of UV light,and the authenticity of the information can be further identified by thermal stimulation.Our fluorescent organohydrogel can act as an effective anti-counterfeiting label to improve the information security and protect the information from being cracked.展开更多
Pure organic room-temperature phosphorescence (RTP) materials have been attracting much attention recently. Herein, we report a facile approach combining heavy atom effect and external solvent stimuli to realize RTP. ...Pure organic room-temperature phosphorescence (RTP) materials have been attracting much attention recently. Herein, we report a facile approach combining heavy atom effect and external solvent stimuli to realize RTP. N-Allylquinolinium bromide under 365 nm UV exhibited intense green RTP emission with response upon adding chloroform. This interesting phenomenon endowed N-allylquinolinium bromide great potential as an anti-counterfeiting material.展开更多
The development of solid-state smart materials, in particular those showing photoresponsive luminescence, is highly desirable for their cutting edge applications in displays, sensors, data-storage, and anticounterfeit...The development of solid-state smart materials, in particular those showing photoresponsive luminescence, is highly desirable for their cutting edge applications in displays, sensors, data-storage, and anticounterfeiting. However, to achieve both excellent photoresponsive performance and bright luminescence in solid state remains challenge. Herein, we integrate a novel photochromic fluorophore YL into flexible polymer chains, thereby enabling the resultant polymer PYL with reversible photoisomerization upon aggregation. Remarkably, the polymer PYL possesses excellent photochromic properties and aggregationinduced emission(AIE) activity, which can be attributed to the photoactive YL moiety. Upon light exposure, its film exhibits reversibly off-to-on fluorescent modulation with quick response, high emission efficiency and signal contrast, sharply different from the weak emission in solution. The novel photoresponsive AIE polymer with invisible/visible color and fluorescence transformation allows for advanced anti-counterfeiting applications. This work provides an efficient platform for constructing solid-state photocontrollable luminescent materials.展开更多
Recently,the ultraviolet(UV)persistent luminescence material(PLM)has attracted extensive attention.However,the design and development of new UV PLM and exploring their promising advanced application remain challenges....Recently,the ultraviolet(UV)persistent luminescence material(PLM)has attracted extensive attention.However,the design and development of new UV PLM and exploring their promising advanced application remain challenges.Here,we developed a new dopant-free self-activated UVA PLM,Zn_(2)Al_(2)SiO_(7),which could be applied in anti-counterfeiting field.Zn_(2)Al_(2)SiO_(7)shows UVA persistent luminescence(PersL)peaking at 380 nm after 254 nm UV lamp excitation.Addition of Yb^(3+),the UVA PersL intensity and time are raised obviously,and the UVA PersL time lasts more than 24 h.In addition,Yb^(3+)-doped Zn_(2)Al_(2)SiO_(7)exhibits photostimulated properties with different light source.Finally,we design anticounterfeiting pattern based on intensity and time resolution from PersL of Zn_(2)Al_(2)SiO_(7),showing its advantages in the anti-counterfeiting field.展开更多
Counterfeiting is one of the most serious problems in the consumer market. One promising approach for anti-counterfeiting is to attach a low-cost Radio-frequency Identification (RFID) tag to the product authentication...Counterfeiting is one of the most serious problems in the consumer market. One promising approach for anti-counterfeiting is to attach a low-cost Radio-frequency Identification (RFID) tag to the product authentication. In this paper, we propose an RFID system for detecting counterfeiting products. This RFID system consists of the tag authentication protocol and the database correction protocol. We use the tag authentication protocol for authenticating tags without revealing their sensitive information. This protocol also allows the customer to freely inquire the tag. To prevent the widespread of the counterfeit products, we use the tag status information along with tag identity information. Meanwhile, the database correction protocol guarantees the correctness of the tag status. Our anti-counterfeiting system is the first work considering the seller who plays an important role in the consumer product supply chain. Finally, we show that anti-counterfeiting system is quite secure against counterfeiting and the tag authentication protocol is lightweight enough to be implemented in RFID-based applications.展开更多
The developme nt of high-level an ti-co un terfeiti ng tech niq ues is of great sig nifica nee in econo mics and security issues.However,i ntricate read ing methods are required to obta in multi-level info rmati on st...The developme nt of high-level an ti-co un terfeiti ng tech niq ues is of great sig nifica nee in econo mics and security issues.However,i ntricate read ing methods are required to obta in multi-level info rmati on stored in differe nt colors,which greatly limits the applicati on of an ti-co un terfeit ing tech no logy on sol ving real world problems.Here in,we realize multicolor information anti-counterfeiting under simply external stimulation by utilizing the functional groups and multiple emission centers of lanthanide metal organic framework(Ln-MOFs)to tune luminescence color.Water responsive multicolor luminescence represented by both the tunable color from red to blue within the visible region and high sensitive responsivity has bee n achieved,owing to the in creased nonr adiative decay pathways and enhan ced Eu3+-to-liga nd en ergy back tra nsfer.Remarkably,i nfo rmatio n hidde n in differe nt colors n eeds to be read with a specific water content,which can be used as an en crypti on key to en sure the security of the info rmati on for high-level an ti-co un terfeiti ng.展开更多
With the rapid development of science and technology,the high-security-level anti-counterfeiting technique is essential for ensuring property or information security.In this work,we prepared micron NaYTiO_(4):Bi/Er(NY...With the rapid development of science and technology,the high-security-level anti-counterfeiting technique is essential for ensuring property or information security.In this work,we prepared micron NaYTiO_(4):Bi/Er(NYT:Bi/Er) phosphors with integrating up-conversion(UC) photoluminescence,downshifting(DS) emission,phosphorescence and photochromism(PC) performances for advanced multiple anti-counterfeiting application.Owing to the abundant energy levels of Er^(3+)ions,the UC and DS luminescence behaviors are anticipated.Specifically,the yellow-green emission of Er^(3+)ions can be observed upon 980 nm excitation,and the bright green emission is demonstrated under 281 or 254 nm excitation due to the energy transitions of Er^(3+)ions and the energy transfer process from Bi^(3+)to Er^(3+)ions.Besides,the introduction of Bi^(3+)ions generates defect levels in the matrix and thus leads to phosphorescence.Furthermore,the repeatable PC performance could be triggered by the 365 nm irradiation and vanished with 450 nm illumination or thermal stimulation.To verify the practical usability of NYT:Bi/Er phosphors on anti-counterfeiting applications,some experiments are designed and successfully executed.It is believed that the NYT:Bi/Er phosphors can be a promising candidate for high-security-level multiple anti-counterfeiting.展开更多
The authenticity identification of anti-counterfeiting codes based on mobile phone platforms is affected by lighting environment,photographing habits,camera resolution and other factors,resulting in poor collection qu...The authenticity identification of anti-counterfeiting codes based on mobile phone platforms is affected by lighting environment,photographing habits,camera resolution and other factors,resulting in poor collection quality of anti-counterfeiting codes and weak differentiation of anti-counterfeiting codes for high-quality counterfeits.Developing an anticounterfeiting code authentication algorithm based on mobile phones is of great commercial value.Although the existing algorithms developed based on special equipment can effectively identify forged anti-counterfeiting codes,the anti-counterfeiting code identification scheme based on mobile phones is still in its infancy.To address the small differences in texture features,low response speed and excessively large deep learning models used in mobile phone anti-counterfeiting and identification scenarios,we propose a feature-guided double pool attention network(FG-DPANet)to solve the reprinting forgery problem of printing anti-counterfeiting codes.To address the slight differences in texture features in high-quality reprinted anti-counterfeiting codes,we propose a feature guidance algorithm that creatively combines the texture features and the inherent noise feature of the scanner and printer introduced in the reprinting process to identify anti-counterfeiting code authenticity.The introduction of noise features effectively makes up for the small texture difference of high-quality anti-counterfeiting codes.The double pool attention network(DPANet)is a lightweight double pool attention residual network.Under the condition of ensuring detection accuracy,DPANet can simplify the network structure as much as possible,improve the network reasoning speed,and run better on mobile devices with low computing power.We conducted a series of experiments to evaluate the FG-DPANet proposed in this paper.Experimental results show that the proposed FG-DPANet can resist highquality and small-size anti-counterfeiting code reprint forgery.By comparing with the existing algorithm based on texture,it is shown that the proposed method has a higher authentication accuracy.Last but not least,the proposed scheme has been evaluated in the anti-counterfeiting code blurring scene,and the results show that our proposed method can well resist slight blurring of anti-counterfeiting images.展开更多
In order to increase the watermarking capacity and improve the anti-counterfeiting performance of quick response （QR） two-dimensional （2D） barcode based on digital watermarking technique, this paper proposes a kin...In order to increase the watermarking capacity and improve the anti-counterfeiting performance of quick response （QR） two-dimensional （2D） barcode based on digital watermarking technique, this paper proposes a kind of graying algorithm for binary image to make transform domain watermarking methods possible. Based on the graying Mgorithm, the quantizatiombased watermarking scheme in discrete wavelet transform （DWT） domain is then designed. The experiments show that the proposed watermarking scheme for QR 2D barcode greatly improves anti-counterfeiting performance without loss of any barcode information.展开更多
Development of new anti-counterfeiting technology with dynamic optical signals has drawn great attention,but the use of multiple external stimulus or long-time light irradiation inevitably increases the operation comp...Development of new anti-counterfeiting technology with dynamic optical signals has drawn great attention,but the use of multiple external stimulus or long-time light irradiation inevitably increases the operation complexity and limits the practical application.In this work,we report the design of new fluorescence-phosphorescence dual-emission materials based on carbon dots(CDs)-engineered gold nanoclusters(AuNCs)in silica for advanced luminescent anti-counterfeiting.In particular,co-encapsulation of phosphorescent CDs and fluorescent AuNCs by rigid silica matrix enables the construction of a dual-emission system(AuNCs/CDs@SiO_(2))in aqueous phase.The AuNCs/CDs@SiO_(2) composite displayed significant fluorescence color change based on inner filter effect,as confirmed by in-depth spectral and photophysical characterization.Highly reversible and dynamic color switching between magenta fluorescence and green phosphorescence was easily achieved by simply switching on/off the ultraviolet(UV)irradiation.Potential utility of dual-emitting AuNCs/CDs@SiO_(2) as novel dynamic anti-counterfeiting materials has been successfully demonstrated,including anti-counterfeiting ink,ink-free optical printing film,and information encryption.The present aqueous-phase fluorescence-phosphorescence dual-emission system exhibits two types of anti-counterfeiting mode without introducing external stimulus,increasing the difficulty of imitation and duplication.This work provides a straightforward and generable strategy to design advanced optical anti-counterfeiting materials by combining phosphorescent materials with other fluorophores via reasonable engineering strategy.展开更多
基金supported by the National Natural Science Foundation of China(Nos.22201057 and 22472044)Zhejiang Provincial Natural Science Foundation of China(Nos.LR22B010001 and LQ23B010001)。
文摘In this work,we synthesize two luminescent Pt(Ⅱ)complexes using differentπ-conjugated bidentate ligands.Both complexes are assembled into three-dimensional(3D)networks through non-classical intermolecular interactions in the crystal state.Unexpectedly,substituting pyridine with the more extensivelyπ-conjugated quinoline significantly increases the dihedral angles between the phenyl and quinolyl groups of the bidentate ligands.This alteration disrupts theπ-πinteractions between molecules,resulting in distinct optical properties upon exposure to external stimuli.By integrating these complexes into polymers,we fabricate electrospun films containing luminescent nanofibers that exhibit reversible optical changes.These findings have paved the way for the development of high-performance optical encryption and anti-counterfeiting materials,achieved through the employment of simple chromophores.
基金funded by the National Natural Science Foundation of China(Nos.22101267 and 82103686)the Natural Science Foundation of Henan Province(202300410477 and 24230042123)the China Postdoctoral Science Foundation(Nos.2021M692905 and 2024T170832).
文摘The application of aggregation-induced emission(AIE)materials in biological imaging holds multiple significances,including improving detection sensitivity and specificity,optimizing the imaging process,expanding the scope of application,and promoting advancements in biomedical research.In this work,the propeller ligand was constructed through McMurry coupling reaction and Suzuki coupling reaction by using dimethoxybenzophenone as the starting material.Then,an imine condensation reaction was carried out in chloroform solution,using a 3:2 molar ratio of precursor to tri(2-aminoethyl)amine to synthesize C3 symmetric porous organic cage CB.The structures of the compounds were determined by nuclear magnetic resonance spectroscopy(NMR),electrospray ionization mass spectrometry(ESI-MS)and Fourier transform infrared spectroscopy(FT-IR).The optical investigation results reveal that ligand L-B and the porous organic cage C_(B) demonstrate remarkable aggregation-induced emission(AIE)properties in a tetrahydrofuran/water mixed solvent system,along with a pronounced response to tetrahydrofuran vapor stimuli.Consequently,Furthermore,given its unique cage-like structure,high quantum yield,and outstanding AIE behavior,the porous organic cage C_(B) holds promise for applications in cell imaging.
基金Project supported by the Science and Technology International Cooperation Project of Qinghai Province (2022-HZ-807)the Open Project Salt Lake Chemical Engineering Research Complex,Qinghai University (2023-DXSSZZ-04)。
文摘Er^(3+)-and Tm^(3+)-doped Ca_(x)Sr_(2-x)Nb_(2)O_(7)(C_(x)S_(2-x)N,x=0.6,0.8,1,0,1.2,1,4) phosphors with layered pe rovskite structure were designed.These phosphors exhibit a dominant emission peak at 549 nm under980 nm laser excitation,attributed to the^(4)S_(3/2)→^(4)I_(15/2)transition.By increasing the content of Ca^(2+),the crystal field regulation of rare earth ions is realized and the luminescence enhancement is induced,which is manifested by the increase of^(2)H_(11/2),^(4)S_(3/2)→^(4)I_(15/2)emission.Furthermore,the temperature sensing sensitivities of C_(0.6)S_(1.4)N:Er,Tm and C_(0.6)S_(1.4)N:Er,Tm based on non-thermally coupled energy levels were studied.Finally,an anti-counterfeiting imprint was prepared using phosphors,which have high brightness and excellent photothermal stability.This work not only confirms that closer ionic radii substitution enables to increase the electronic density of states,improve the crystal field symmetry and enhance the luminescence,but also provides a promising phosphor system for temperature sensing and anti-counterfeiting applications,opening up new prospects in the optimization of the optical properties of phosphors.
文摘Counterfeiting is still a pervasive global issue,affecting multiple industries and hindering industrial innovation,while causing substantial financial losses,reputational damage,and risks to consumer safety.From luxury goods and pharmaceuticals to electronics and automotive parts,counterfeit products infiltrate supply chains,leading to a loss of revenue for legitimate businesses and undermining consumer trust.Traditional anti-counterfeiting measures,such as holograms,serial numbers,and barcodes,have proven to be insufficient as counterfeiters continuously develop more sophisticated replication techniques.As a result,there is a growing need for more advanced,secure,and reliable methods to prevent counterfeiting.This paper presents a novel,holistic anti-counterfeiting platform that integrates Near Field Communication(NFC)-enabled mobile applications with blockchain technology to provide an innovative,secure,and consumer-friendly authentication mechanism.Our approach addresses key gaps in existing solutions by incorporating dynamic product identifiers,which make replication significantly more difficult.The system enables consumers to verify the authenticity of products instantly using their smartphones,enhancing transparency and trust in the supply chain.Blockchain technology plays a crucial role in our proposed solution by providing an immutable,decentralized ledger that records product authentication data.This ensures that product verification records cannot be tampered with or altered,adding a layer of security that is absent in conventional systems.Additionally,NFC technology enhances security by offering unique identification capabilities,enabling real-time product verification.To validate the effectiveness of the proposed system,real-world testing was conducted across different industries.The results demonstrated the platform’s ability to significantly reduce counterfeit products in the supply chain,offering businesses and consumers a more robust and reliable authentication method.By leveraging the combined strengths of blockchain and NFC,this solution represents a significant advancement in the fight against counterfeiting,ensuring enhanced security,transparency,and consumer trust.
基金financially supported by the National Natural Science Foundation of China(No.22205249)Zhejiang Provincial Natural Science Foundation of China(No.LQ23B040002)+2 种基金the Sino-German Mobility Program(No.M-0424)Ningbo International Cooperation Project(No.2023H019)China Postdoctoral Science Foundation(Nos.2021TQ0341,2022M723252)。
文摘Stimulus-responsive room-temperature phosphorescence(RTP)materials have gained significant attention for their important optoelectronic application prospects.However,the fabrication strategy and underlying mechanism of stimulus-responsive RTP materials remain less explored.Herein,we present a reliable strategy for achieving pH-responsive RTP materials by integrating poly(vinyl alcohol)(PVA)with carboxylic acid or amino group functionalized terpyridine(Tpy)derivatives.The resulting Tpy derivativesbased RTP materials displayed reversible changes in emission color,intensity,and lifetime of both prompt and delayed emission.Notably,the RTP emission undergoes a significant diminish upon exposure to acid due to the protonation of Tpy units.Taking advantage of the decent RTP emission and pH-responsiveness of these RTP films,a spatial-time-resolved anti-counterfeiting application is demonstrated as a proof-ofconcept for largely enhancing the security level.This study not only provides new prospects for developing smart RTP materials but also promotes the advancement of optical anti-counterfeiting applications.
基金Project supported by the National Key Research and Development Program of China (Grant No.2021YFB2012600)the Shanghai Aerospace Science and Technology Innovation Fund,China (Grant No.SAST-2022-102)。
文摘Counterfeiting of modern banknotes poses a significant challenge,prompting the use of various preventive measures.One such measure is the magnetic anti-counterfeiting strip.However,due to its inherent weak magnetic properties,visualizing its magnetic distribution has been a longstanding challenge.In this work,we introduce an innovative method by using a fiber optic diamond probe,a highly sensitive quantum sensor designed specifically for detecting extremely weak magnetic fields.We employ this probe to achieve high-resolution imaging of the magnetic fields associated with the RMB 50denomination anti-counterfeiting strip.Additionally,we conduct computer simulations by using COMSOL Multiphysics software to deduce the potential geometric characteristics and material composition of the magnetic region within the anti-counterfeiting strip.The findings and method presented in this study hold broader significance,extending the RMB 50 denomination to various denominations of the Chinese currency and other items that employ magnetic anti-counterfeiting strips.These advances have the potential to significantly improve and promote security measures in order to prevent the banknotes from being counterfeited.
基金Project supported by the National Natural Science Foundation of China(11575059)Natural Science Foundation of Huzhou City(2018YZ08)。
文摘In this study,the hexagonal NaYF_(4):Yb^(3+)/Ho^(3+)/Ce^(3+) microcrystals were synthesized controllably,and upconversion luminescence excited at 940 nm and its application in temperature-responsive anti-counterfeiting are reported.It is clarified that the Ln^(3+)(Ln=Y+Yb+Ho+Ce)density ratio of bottom plane to side plane in the unit cell can be regulated by Ce^(3+) doping.It is also proved that the energy transfer of Yb^(3+) to Ho^(3+) is responsible for the activation of Ho^(3+)under 940 nm excitation,while the cross relaxation between Ho^(3+)and Ce^(3+)participates in the redistribution of electron population of^(5)S_(2)/^(5)F_(4)and^(5)F_(5)levels.Both theory and experiment confirm that the intensity ratio of red to green emission(I_(R)/I_(G))as a function of temperature as an independent variable has good linear characteristics in the temperature range of 300-500 K.Due to the good responsiveness of multicolor luminescence to temperature,the hexagonal NaYF_(4):Yb^(3+)/Ho^(3+)/Ce^(3+) with tunable morphology is a promising candidate for advanced temperature-responsive upconversion anti-counterfeiting.Our results provide a new pathway for the controllable synthesis of hexagonal NaYF_(4)microcrystals as well as the regulation of upconversion luminescence that is excited by wavelengths other than 980 nm and its application in anti-counterfeiting.
基金Project supported by the Chinese Ministry of Education (208005)Young Scientist Backbone of Heilongjiang Common Higher University (1154G03)
文摘A benzoic acid rare earth(Tb) complex was synthesized and characterized.The excitation and emission spectra of the complex were investigated,and then pure organic complex was incorporated with inorganic matrices(SiO2) through sol-gel method.The composition and structure of the hybrid complex was characterized through the IR spectra,TG,TEM and fluorescent spectrometer.Furthermore,the polypropylene(PP) fluorescent fiber with the organic-inorganic hybrid was prepared by melt spinning.The fluorescent and mechanical properties of the fiber were also tested.The results showed that after sol-gel coating the average particulate dimension of the hybrid rare earth complex was less than 100 nm and thermal stability was improved.Meanwhile,the fiber possessed excellent fluorescent and mechanical properties,which could be used as a candidate applied to excellent fluorescent anti-counterfeiting fiber.
基金supported by the Natural Science Foundation of Hubei Province for Distinguished Young Scholars (No. 2019CFA056)the Fundamental Research Funds for the Central Universities and Wuhan University and the Fundamental Research Funds for the Central Universities (No. 2042021kf0226)。
文摘Carbon dots(CDs) with fluorescence(FL) and room-temperature phosphorescence(RTP) optical properties have attracted dramatically growing interest in anti-counterfeiting application. Herein, color-tunable and stable FL and ultralong RTP(to naked eyes ~14 s) are successfully achieved in CDs system. Encoding information and patterns fabricated by directly screen-printing method are invisible to eyes under natural light. Interestingly, clear and multicolor patterns with tunable FL and RTP emissions are identified under the 365 nm, 395 nm and 465 nm excitation and removal of them, indicating potential application of carbon dots with different FL and RTP outputs in the high-level photonic anti-counterfeiting field.
基金supported by the National Key R&D Program of China(No.2022YFB3204300)the National Natural Science Foundation of China(No.52103246)+1 种基金Zhejiang Provincial Natural Science Foundation,China(No.LQ22E030015)Natural Science Foundation of Ningbo,China(No.20221JCGY010301).
文摘Anti-counterfeiting labels with various fluorescent colors are of great importance in information encryption-decryption,but are still limited to static information display.Therefore,it is urgent to develop new materials and encryption-decryption logic for improving the security level of secret information.In this study,an organohydrogel made up of poly(N,N-dimethylacrylamide)(pDMA)hydrogel network and polyoctadecyl methacrylate(pSMA)organogel network that copolymerized with two fluorophores,6-acrylamidopicolinic acid moieties(6APA,fluorescent ligand)and spiropyran units(SPMA,photochromic monomer),was prepared by a two-step interpenetrating method.As UV light of 365nm and 254nm can both cleave C_(spiro)-O bonds of SPMA,and the green fluorescence of 6APA-Tb^(3+) can only be excited by 254nm light,the organohydrogel displays yellow and red under the irradiation of 254nm and 365 nm,respectively.In addition to wavelength selectivity,these two fluorophores are thermal-responsive,leading to the fluorescence variation of the organohydrogel during heating process.As a result,secret information loaded on the organohydrogel can be decrypted by the irradiation of UV light,and the authenticity of the information can be further identified by thermal stimulation.Our fluorescent organohydrogel can act as an effective anti-counterfeiting label to improve the information security and protect the information from being cracked.
基金the financial support from the Instrument Developing Project of the Chinese Academy of Sciences (No. YJKYYQ20170009)the National Natural Science Foundation of China(NSFC Nos. 21722603 and 21871083)the Innovation Program of Shanghai Municipal Education Commission
文摘Pure organic room-temperature phosphorescence (RTP) materials have been attracting much attention recently. Herein, we report a facile approach combining heavy atom effect and external solvent stimuli to realize RTP. N-Allylquinolinium bromide under 365 nm UV exhibited intense green RTP emission with response upon adding chloroform. This interesting phenomenon endowed N-allylquinolinium bromide great potential as an anti-counterfeiting material.
基金financially supported by the National Natural Science Foundation of China for Science Center Program (No. 21788102)Creative Research Groups (No. 21421004)+4 种基金Key Project (No. 21636002)Shanghai Pujiang Program (No. 20PJ1402900)National key Research and Development Program (No. 2016YFA0200300)Shanghai Municipal Science and Technology Major Project (No. 2018SHZDZX03)Program of Introducing Talents of Discipline to Universities (No. B16017)。
文摘The development of solid-state smart materials, in particular those showing photoresponsive luminescence, is highly desirable for their cutting edge applications in displays, sensors, data-storage, and anticounterfeiting. However, to achieve both excellent photoresponsive performance and bright luminescence in solid state remains challenge. Herein, we integrate a novel photochromic fluorophore YL into flexible polymer chains, thereby enabling the resultant polymer PYL with reversible photoisomerization upon aggregation. Remarkably, the polymer PYL possesses excellent photochromic properties and aggregationinduced emission(AIE) activity, which can be attributed to the photoactive YL moiety. Upon light exposure, its film exhibits reversibly off-to-on fluorescent modulation with quick response, high emission efficiency and signal contrast, sharply different from the weak emission in solution. The novel photoresponsive AIE polymer with invisible/visible color and fluorescence transformation allows for advanced anti-counterfeiting applications. This work provides an efficient platform for constructing solid-state photocontrollable luminescent materials.
基金Project supported by the National Natural Science Foundation of China(61705228,62105333,11864015)the Natural Science Foundation of Fujian Province,China(2019J05159)。
文摘Recently,the ultraviolet(UV)persistent luminescence material(PLM)has attracted extensive attention.However,the design and development of new UV PLM and exploring their promising advanced application remain challenges.Here,we developed a new dopant-free self-activated UVA PLM,Zn_(2)Al_(2)SiO_(7),which could be applied in anti-counterfeiting field.Zn_(2)Al_(2)SiO_(7)shows UVA persistent luminescence(PersL)peaking at 380 nm after 254 nm UV lamp excitation.Addition of Yb^(3+),the UVA PersL intensity and time are raised obviously,and the UVA PersL time lasts more than 24 h.In addition,Yb^(3+)-doped Zn_(2)Al_(2)SiO_(7)exhibits photostimulated properties with different light source.Finally,we design anticounterfeiting pattern based on intensity and time resolution from PersL of Zn_(2)Al_(2)SiO_(7),showing its advantages in the anti-counterfeiting field.
文摘Counterfeiting is one of the most serious problems in the consumer market. One promising approach for anti-counterfeiting is to attach a low-cost Radio-frequency Identification (RFID) tag to the product authentication. In this paper, we propose an RFID system for detecting counterfeiting products. This RFID system consists of the tag authentication protocol and the database correction protocol. We use the tag authentication protocol for authenticating tags without revealing their sensitive information. This protocol also allows the customer to freely inquire the tag. To prevent the widespread of the counterfeit products, we use the tag status information along with tag identity information. Meanwhile, the database correction protocol guarantees the correctness of the tag status. Our anti-counterfeiting system is the first work considering the seller who plays an important role in the consumer product supply chain. Finally, we show that anti-counterfeiting system is quite secure against counterfeiting and the tag authentication protocol is lightweight enough to be implemented in RFID-based applications.
基金This work was supported by the National Natural Science Foundation of China(Nos.52025131,51632008,51772268,and 61721005)Zhejiang Provincial Natural Science Foundation of China(No.LD18E020001).
文摘The developme nt of high-level an ti-co un terfeiti ng tech niq ues is of great sig nifica nee in econo mics and security issues.However,i ntricate read ing methods are required to obta in multi-level info rmati on stored in differe nt colors,which greatly limits the applicati on of an ti-co un terfeit ing tech no logy on sol ving real world problems.Here in,we realize multicolor information anti-counterfeiting under simply external stimulation by utilizing the functional groups and multiple emission centers of lanthanide metal organic framework(Ln-MOFs)to tune luminescence color.Water responsive multicolor luminescence represented by both the tunable color from red to blue within the visible region and high sensitive responsivity has bee n achieved,owing to the in creased nonr adiative decay pathways and enhan ced Eu3+-to-liga nd en ergy back tra nsfer.Remarkably,i nfo rmatio n hidde n in differe nt colors n eeds to be read with a specific water content,which can be used as an en crypti on key to en sure the security of the info rmati on for high-level an ti-co un terfeiti ng.
基金supported by the Introduced Innovative R&D Team Project of "The Pearl River Talent Recruitment Program"of Guangdong Province (No.2019ZT08C321)Guangdong Basic and Applied Basic Research Foundation (No.2019A1515110443)the National Natural Science Foundation of China (No.51872327)。
文摘With the rapid development of science and technology,the high-security-level anti-counterfeiting technique is essential for ensuring property or information security.In this work,we prepared micron NaYTiO_(4):Bi/Er(NYT:Bi/Er) phosphors with integrating up-conversion(UC) photoluminescence,downshifting(DS) emission,phosphorescence and photochromism(PC) performances for advanced multiple anti-counterfeiting application.Owing to the abundant energy levels of Er^(3+)ions,the UC and DS luminescence behaviors are anticipated.Specifically,the yellow-green emission of Er^(3+)ions can be observed upon 980 nm excitation,and the bright green emission is demonstrated under 281 or 254 nm excitation due to the energy transitions of Er^(3+)ions and the energy transfer process from Bi^(3+)to Er^(3+)ions.Besides,the introduction of Bi^(3+)ions generates defect levels in the matrix and thus leads to phosphorescence.Furthermore,the repeatable PC performance could be triggered by the 365 nm irradiation and vanished with 450 nm illumination or thermal stimulation.To verify the practical usability of NYT:Bi/Er phosphors on anti-counterfeiting applications,some experiments are designed and successfully executed.It is believed that the NYT:Bi/Er phosphors can be a promising candidate for high-security-level multiple anti-counterfeiting.
基金This work is supported by Supported by the National Key Research and Development Program of China under Grant No.2020YFF0304902the Science and Technology Research Project of Jiangxi Provincial Department of Education under Grant No.GJJ202511。
文摘The authenticity identification of anti-counterfeiting codes based on mobile phone platforms is affected by lighting environment,photographing habits,camera resolution and other factors,resulting in poor collection quality of anti-counterfeiting codes and weak differentiation of anti-counterfeiting codes for high-quality counterfeits.Developing an anticounterfeiting code authentication algorithm based on mobile phones is of great commercial value.Although the existing algorithms developed based on special equipment can effectively identify forged anti-counterfeiting codes,the anti-counterfeiting code identification scheme based on mobile phones is still in its infancy.To address the small differences in texture features,low response speed and excessively large deep learning models used in mobile phone anti-counterfeiting and identification scenarios,we propose a feature-guided double pool attention network(FG-DPANet)to solve the reprinting forgery problem of printing anti-counterfeiting codes.To address the slight differences in texture features in high-quality reprinted anti-counterfeiting codes,we propose a feature guidance algorithm that creatively combines the texture features and the inherent noise feature of the scanner and printer introduced in the reprinting process to identify anti-counterfeiting code authenticity.The introduction of noise features effectively makes up for the small texture difference of high-quality anti-counterfeiting codes.The double pool attention network(DPANet)is a lightweight double pool attention residual network.Under the condition of ensuring detection accuracy,DPANet can simplify the network structure as much as possible,improve the network reasoning speed,and run better on mobile devices with low computing power.We conducted a series of experiments to evaluate the FG-DPANet proposed in this paper.Experimental results show that the proposed FG-DPANet can resist highquality and small-size anti-counterfeiting code reprint forgery.By comparing with the existing algorithm based on texture,it is shown that the proposed method has a higher authentication accuracy.Last but not least,the proposed scheme has been evaluated in the anti-counterfeiting code blurring scene,and the results show that our proposed method can well resist slight blurring of anti-counterfeiting images.
基金the National Natural Science Foundation of China(No.60903203)the Fujian Educational Bureau JK Projects(No.JK2012044)the Xiamen Municipal Science and Technology Plan Projects(No.3502Z20103036)
文摘In order to increase the watermarking capacity and improve the anti-counterfeiting performance of quick response （QR） two-dimensional （2D） barcode based on digital watermarking technique, this paper proposes a kind of graying algorithm for binary image to make transform domain watermarking methods possible. Based on the graying Mgorithm, the quantizatiombased watermarking scheme in discrete wavelet transform （DWT） domain is then designed. The experiments show that the proposed watermarking scheme for QR 2D barcode greatly improves anti-counterfeiting performance without loss of any barcode information.
基金This work is supported by the National Natural Science Foundation of China(No.22274131)the Shenzhen Science and Technology Program(No.JCYJ20220530161800001)the Innovation Foundation for Doctor Dissertation of Northwestern Polytechnical University(No.CX2024054).
文摘Development of new anti-counterfeiting technology with dynamic optical signals has drawn great attention,but the use of multiple external stimulus or long-time light irradiation inevitably increases the operation complexity and limits the practical application.In this work,we report the design of new fluorescence-phosphorescence dual-emission materials based on carbon dots(CDs)-engineered gold nanoclusters(AuNCs)in silica for advanced luminescent anti-counterfeiting.In particular,co-encapsulation of phosphorescent CDs and fluorescent AuNCs by rigid silica matrix enables the construction of a dual-emission system(AuNCs/CDs@SiO_(2))in aqueous phase.The AuNCs/CDs@SiO_(2) composite displayed significant fluorescence color change based on inner filter effect,as confirmed by in-depth spectral and photophysical characterization.Highly reversible and dynamic color switching between magenta fluorescence and green phosphorescence was easily achieved by simply switching on/off the ultraviolet(UV)irradiation.Potential utility of dual-emitting AuNCs/CDs@SiO_(2) as novel dynamic anti-counterfeiting materials has been successfully demonstrated,including anti-counterfeiting ink,ink-free optical printing film,and information encryption.The present aqueous-phase fluorescence-phosphorescence dual-emission system exhibits two types of anti-counterfeiting mode without introducing external stimulus,increasing the difficulty of imitation and duplication.This work provides a straightforward and generable strategy to design advanced optical anti-counterfeiting materials by combining phosphorescent materials with other fluorophores via reasonable engineering strategy.
