X-ray irradiated La_(2)Ti_(2)O_(7):Pr^(3+)was found to show long-time sustainable mechanoluminescence(ML),which can realize the high sensitivity and real time detection of stress burst for more than 72 h.Under the exc...X-ray irradiated La_(2)Ti_(2)O_(7):Pr^(3+)was found to show long-time sustainable mechanoluminescence(ML),which can realize the high sensitivity and real time detection of stress burst for more than 72 h.Under the excitation of X-ray,La_(2)Ti_(2)O_(7):Pr^(3+)shows red ML emissions located at 610,624 and 638 nm,which are similar to the afterglow emission spectrum and can be ascribed to(1)^D_(2)-^(3)H_(4),^(3)P_(0)-(3)^H_(4)and (3)^P_(0)-^(3)H_(2)of Pr^(3+).And the linear increases of compressive load can induce the linear increases of ML intensity of the sample,indicating that the X-ray induced ML emission can be utilized to accurately detect the stress applied on the object.Furthermore,X-ray irradiated La_(2)Ti_(2)O_(7):Pr^(3+)possesses excellent stability and the repeatability of ML emission and the ML signals can keep stable even 50 load cycles after 1 h dacay.The thermoluminescence results suggest that abundant electrons are trapped in shallow and deep answered for stable ML emission.More importantly,the deeply trapped electrons induced ML emissions from X-ray irradiated La_(2)Ti_(2)O_(7):Pr^(3+)can be utilized to detect the stress bursts for a long time.When the sample is recharged by 5 min X-ray irradiation once,within 24 h decay,the 1500 N burst among many 1000 N cycles can be clearly detected,and the signal to noise ratio(S/N) reaches 1.32 and 1.26 after 12 and24 h decay,respectively.And even after 72 h decay,the S/N of 2500 N still arrives at 1.23 and that of4000 N reaches 1.97,indicative of long-time high sensitivity detection of abnormal stress.All these results suggest that the X-ray-irradiated La_(1.97)Ti_(2)O_(7):0.03Pr^(3+)/resin sample can realize the high sensitivity and real time detection of stress burst for more than 72 h,which thus possesses great potential application in early warning of the emergency disasters such as bridge fracture,tunnel collapse and so on.展开更多
Mechano luminescence(ML),which involves the emission of light under mechanical stimuli,shows great potential in various applications such as sensing,imaging,and energy harvesting.Current research suggests that the lum...Mechano luminescence(ML),which involves the emission of light under mechanical stimuli,shows great potential in various applications such as sensing,imaging,and energy harvesting.Current research suggests that the luminescence mechanism of ML is typically connected to specific defects present within the material.In this study,we focus on the investigation of ML defects in Pr^(3+)-doped NaNbO_(3)/LiNbO_(3)heterojunctions,employing a combination of experimental and theoretical approaches.Through experimental analysis,we confirmed the presence of the heterojunction and its influence on ML intensity,and the optimal doping ratio for the heterojunction in ML was established.Furthermore,we examined the influence of varying Pr^(3+)doping concentrations on ML behavior and a proof-of-concept was demonstrated using the X-rays charged heterostructural phosphor as a stress sensor for biological applications.The position and concentration of internal defects in the ML material were scrutinized through thermo luminescence tests employing the variable heating rate method and positron annihilation.Complementing the experimental findings,theoretical simulations were conducted to elucidate the underlying mechanisms responsible for the observed ML defects.Density functional theory calculations were employed to investigate the energy levels,charge transfer processes,and lattice distortions within the heterojunctions under mechanical stress.Theoretical predictions were compared and validated against the experimental results.The integration of experimental and theoretical approaches provides a comprehensive understanding of the ML behavior of Pr^(3+)-doped NaNbO_(3)/LiNbO_(3)heterojunctions.The insights gained from this research contribute to the development of novel ML materials and pave the way for their applications in next-generation sensing and energy conversion devices.展开更多
Mechanoluminescence(ML)materials have shown tremendous application potential due to their luminescent properties stimulated by mechanical energy.Owing to the narrow awareness of alterations in the crystal field enviro...Mechanoluminescence(ML)materials have shown tremendous application potential due to their luminescent properties stimulated by mechanical energy.Owing to the narrow awareness of alterations in the crystal field environment of materials,the ML performance optimization is severely restricted.Here,a novel strategy of doping Y^(3+)into SrAl_(2)-_(x)Y_(x)O_(4):Eu^(2+),Dy^(3+)phosphors was employed by solid-phase reaction,significantly improving the ML performance.Based on analysis of structure and luminescent properties,it is proved that Y^(3+)occupies Al^(3+)sites,causing lattice expansion and crystal field distortion,altering trap engineering,strengthening carrier de-trapping ability,and improving ML performance.Through thermo luminescence(TL)analysis,the brighter ML behavior can be attributed to the carriers recombination generated by high-density deep traps of 0.836 eV and above.Materials were also investigated in relation to pressure,stability and repeatability and conducive to achieving dynamic anticounterfeiting of personal signature.This study also provides more evidence that doping ions is an efficient tactic for greatly enhancing ML performance.展开更多
The gallate salts are frequently employed as matrix for mechanoluminescence(ML)materials largely due to their plentiful defect energy levels and robust piezoelectric characteristics.Nevertheless,the ML performance of ...The gallate salts are frequently employed as matrix for mechanoluminescence(ML)materials largely due to their plentiful defect energy levels and robust piezoelectric characteristics.Nevertheless,the ML performance of specific gallate materials is inferior to that of sulfides and fluorides and thus requires improvement.To address this issue,it is essential to engineer appropriate lattice defects in order to facilitate the advancement of new elastic ML materials.Therefore,in the present study,a series of Ca_(3)Ga_(4)O_(9):0.01 Bi^(3+),xTb^(3+)(x=0.01,0.02,0.03,0.04,0.05 and 0.06)was synthesized using the traditional high-temperature solid-state method.Furthermore,a non-intrinsic defect control strategy utilising Bi^(3+)ions is presented,which serves to enhance the performance of calcium gallate.The ML intensity is enhanced by 112%in comparison to the undoped samples(concentration of Tb^(3+)is 0.04),resulting in an improved linearity between mechanical loading and ML intensity,along with the achievement of dualmode photoluminescence(PL).By analysing the crystal structure,PL,ML,and thermoluminescence(TL)properties of Ca_(3)Ga_(4)O_(9):Bi^(3+),Tb^(3+)(CGO:Bi^(3+),Tb^(3+)),coupled with the first principles calculations using density functional theory(DFT),the ML mechanism of CGO:Bi^(3+),Tb^(3+)was elucidated.This leads to the development of a versatile anti-counterfeiting device with both flexible and rigid multi-mode capabilities.展开更多
Two new binuclear (europium and lanthanum) beta-diketone complexes Eu0.9La0.1(TTA)(3)Phen and Eu0.5La0.5(TTA)(3)Phen in which Phen is 1,10-phenanthroline, TTA is an anion of thenoyltrifluoroacetone (HTTA) were synthes...Two new binuclear (europium and lanthanum) beta-diketone complexes Eu0.9La0.1(TTA)(3)Phen and Eu0.5La0.5(TTA)(3)Phen in which Phen is 1,10-phenanthroline, TTA is an anion of thenoyltrifluoroacetone (HTTA) were synthesized for the first time. They showed intense photoluminescence (PL) and mechanoluminescence (ML), and had their maximum PL and ML spectra peaked at 613.5 nm with half bandwidth of 10 nm respectively. Their PL and ML intensity were obviously stronger than these from Eu(TTA)(3)Phen. It is considered that binuclear (europium and lanthanum) beta-diketones complexes are promising ML and PL materials.展开更多
A novel self-recoverable mechanoluminescent phosphor Ca_(5)Ga_(6)O_(14)∶Eu^(3+) was developed by the high-tem-perature solid-state reaction method,and its luminescence properties were investigated.Ca_(5)Ga_(6)O_(14)...A novel self-recoverable mechanoluminescent phosphor Ca_(5)Ga_(6)O_(14)∶Eu^(3+) was developed by the high-tem-perature solid-state reaction method,and its luminescence properties were investigated.Ca_(5)Ga_(6)O_(14)∶Eu^(3+)can produce red mechanoluminescence,and importantly,it shows good repeatability.The mechanoluminescence of Ca_(5)Ga_(6)O_(14)∶Eu^(3+) results from the piezoelectric field generated inside the material under stress,rather than the charge carriers stored in the traps,which can be confirmed by the multiple cycles of mechanoluminescence tests and heat treatment tests.The mechanoluminescence color can be turned from red to green by co-doping varied concentrations of Tb^(3+),which may be meaningful for encrypted letter writing.The encryption scheme for secure communication was devised by harnessing mechanoluminescence patterns in diverse shapes and ASCII codes,which shows good encryption performance.The results suggest that the mechanoluminescence phosphor Ca_(5)Ga_(6)O_(14)∶Eu^(3+),Tb^(3+)may be applied to the optical information encryption.展开更多
During the downconversion process,a high-energy photon undergoes conversion into several low-energy photons,leading to enhanced luminous efficiency in both photoluminescent and electroluminescent devices.This phenomen...During the downconversion process,a high-energy photon undergoes conversion into several low-energy photons,leading to enhanced luminous efficiency in both photoluminescent and electroluminescent devices.This phenomenon has been applied in various fields,including solar cells,plasma display panels,and green lighting technologies such as mercury-free fluorescent lamps.However,the concept of downconversion(quantum cutting)has not been fully explored in the context of mechanoluminescent materials.In this study,we successfully synthesized a heterojunction of CaF_(2)/CaZnOS exhibiting efficient downconversion mechanoluminescence(ML)properties.By controlling the CaF_(2)to CaZnOS ratio and incorporating Tb^(3+)doping,we obtained a highly effective heterojunction structure that significantly enhanced ML.Moreover,we extended this material to several commonly utilized downconversion ion-doping combinations,achieving enhanced ML for Tb^(3+),Pr^(3+),and Yb^(3+)single ions.For the first time,we demonstrate the downconversion(quantum cutting)ML of Tb^(3+)-Yb^(3+)and Pr^(3+)-Yb^(3+)pairs within heterojunction microstructures.This study presents the design and synthesis of a novel heterojunction material capable of realizing downconversion ML,which holds promise for future applications in diverse fields.展开更多
In this study,we investigated a novel multifunctional piezoelectric phosphor LiNbO_(3):1%Pr^(3+),0.5%Zn^(2+),which exhibited outstanding mechanoluminescence(ML)characteristics due to the strategic incorporation of Zn^...In this study,we investigated a novel multifunctional piezoelectric phosphor LiNbO_(3):1%Pr^(3+),0.5%Zn^(2+),which exhibited outstanding mechanoluminescence(ML)characteristics due to the strategic incorporation of Zn^(2+).A dual-regulation mechanism is proposed by adjusting the charge transfer band(CTB)energy level position and optimizing the defect distribution,thus realizing high-brightness,long-term storage,and highly repeatable red emission in ML.The addition of Zn^(2+)can lower the CTB energy level of the phosphor,which leads to the easier transfer of^(3)P_(0)electrons of Pr^(3+)to the^(1)D_(2)energy level through the CTB band,thus enhancing the ML red emission.The introduction of a small amount of Zn^(2+)effectively couple the trap structure with the piezoelectric properties of the material,significantly enhancing ML properties.Notably,the material exhibits excellent ML repeatability and long-term storage,maintaining a strong ML response even after 30 d.Density functional theory calculations of the phosphor confirmed that the doping of Zn^(2+)in LiNbO_(3):1%Pr^(3+)optimized the trap concentration and distribution,thereby improving the ML performance.This multifunctional material holds great potential for use in electromechanical and optoelectronic devices,contributing to the development of smart devices with broader applications.展开更多
Investigation of luminescent materials with efficient photoluminescence(PL)and mechanoluminescence(ML)is significant for the development of both basic theories and industrial applications for new light sources,pressur...Investigation of luminescent materials with efficient photoluminescence(PL)and mechanoluminescence(ML)is significant for the development of both basic theories and industrial applications for new light sources,pressure sensors,and information security.In this study,we obtain a pair of isomorphic europium(Eu)^(3+)-containing coordination polymers(CPs),namely,[Eu(tfpd)_(3)(phen)]_(n)(1)and[Eu(tfpd)_(3)(bipy)]_(n)(2)(tfpd=4,4,4-trifluoro-4-pyridyl-1,3-diketonate,phen=1,10-phenanthroline,bipy=2,2'-bipyridine),which exhibit novel helical chain-like structures that can be extended to 3D supramolecular networks through moderate interchain interactions.The thermostable CPs simultaneously exhibit strong photoluminescence(PL)emissions with high quantum yields and excellent mechanoluminescence(ML)activity with an unusual anti-thermal quenching effect.Careful analyses of the CP crystal structures and optical performances,coupled with theoretical calculations,demonstrate that the PL emission depends on the asymmetric Eu^(3+)coordination spheres,whereas the ML activity is significantly correlated with molecular packing derived from appropriate interchain H-bonding interactions.As these CPs have highly efficient optical activities,they have promising potential applications in pressure sensing,anti-counterfeiting,and fingerprint recognition technologies.展开更多
In this work,we discovered an unexpected mechanoluminescence (ML) phenomena occurring when transforming amorphous into crystalline,due to the stress-induced precipitation of CsPbBr3 perovskite nanocrystals on glass su...In this work,we discovered an unexpected mechanoluminescence (ML) phenomena occurring when transforming amorphous into crystalline,due to the stress-induced precipitation of CsPbBr3 perovskite nanocrystals on glass surface.It is revealed that,unlike the conventional thermal-induced phase transformation mechanism,the breakage of bonding of glass network provides the energy for nucleation and growth,and the shear stress avoids the long-range migration of structural units for crystallization.Such unique ML phenomenon enables the visualization of dynamical force that is inaccessible by common strategy,and so,opens up some novel applications,such as the pressure-sensitive "glassy pencil" to learn people's writing habits,and the pb^2+-detection with good sensitivity and selectivity.These findings not only demonstrate an effective route for the preparation of perovskite materials in a green,time-saving,low cost,and scalable way,enrich the knowledge of glass crystallization mechanism,but also exploit a useful avenue to quantitatively visualize the dynamical force.展开更多
A phenothiazine derivative PtzChol containing non-conjugated chiral cholesterol group was designed and synthesized. By analyzing the single crystal structure of PtzChol carefully, coupled with the circular dichroism(C...A phenothiazine derivative PtzChol containing non-conjugated chiral cholesterol group was designed and synthesized. By analyzing the single crystal structure of PtzChol carefully, coupled with the circular dichroism(CD) signals before and after grinding, it was found that the introduction of cholesterol produced a positive effect on the production of chiral space group, on mechanoluminescence(ML) and room temperature phosphorescence(RTP), and throughout the entire light-emitting process, the CD signal could well reflect the changes of molecular arrangement.展开更多
This article reports a new phosphorescent material,CaZnOS:Cu,that exhibits two types of mechano-optical conversion:mechanical quenching and mechanoluminescence.An intense mechanical quenching of phosphorescence corres...This article reports a new phosphorescent material,CaZnOS:Cu,that exhibits two types of mechano-optical conversion:mechanical quenching and mechanoluminescence.An intense mechanical quenching of phosphorescence corresponding to mechanical stimuli can be achieved in CaZnOS:Cu within a short decay time period.Over time,it gradually changes to mechanoluminescence when a mechanical load is applied.We propose that the mechanical quenching and mechanoluminescence arise from the different roles of shallow and deep traps in CaZnOS:Cu.CaZnOS:Cu has promising applications in monitoring mechanical stress in industrial plants,structures,and living bodies.展开更多
Metal-organic frameworks(MOFs)and mechanoluminescent(ML)materials have been considered as two types of promising materials that have their own application fields.It would be amazing to endow one material with the adva...Metal-organic frameworks(MOFs)and mechanoluminescent(ML)materials have been considered as two types of promising materials that have their own application fields.It would be amazing to endow one material with the advantages of ML and MOFs,thus broadening their applications.However,there are quite few investigations on this topic,and the ML mechanism in ML-MOFs remains unclear.In this study,we proposed a strategy for developing ML-MOFs by doping lanthanide ions into the non-centrosymmetric SBD([Sr(μ-BDC)(DMF)]∞)MOF,and successfully synthesized a series of lanthanide-doped MOFs Ln-SBD(Ln=Tb,Dy,Sm,Eu)and Tb1-xEux-SBD(x=0.2,0.4,0.6,0.8)with multicolor ML.The lanthanide ions were uniformly distributed in the matrix of the SBD-MOF,and occupied the Sr site.The MLMOFs exhibited intense multicolor ML emissions varying from green to yellow to red by changing the co-doping ratios and species of lanthanide ions.The similar ML and photoluminescence(PL)spectra indicated that the ML emission was assigned to the radiative transition from the excited states to the ground states of lanthanide ions.The radiative transition was induced by the electron bombardment process that originated from the piezoelectric effect of the non-centrosymmetric SBD host.In addition,a pioneering temperature sensing research based on ML was carried out,which is promising for realizing dual-functional detection of stress and temperature without excitation light sources.This study gives a unique insight for developing more versatile and interesting smart materials by combining the versatility of MOF with the ML emission,imparting additional values to both MOF and ML materials.Moreover,this study provides a general rule for selecting MOFs with an acentric structure as the host for ML materials.展开更多
A series of Sr_(1.96)Sn_(1-x)Si_(x)O_(4):0.04Sm^(3+)(x=0,0.1,0.15,_(0.2),0.3,0.4)were synthesized from solid-state reaction.The mechanoluminescence(ML)performance of Sr_(1.96)SnO_(4):0.04Sm^(3+)was greatly enhanced b...A series of Sr_(1.96)Sn_(1-x)Si_(x)O_(4):0.04Sm^(3+)(x=0,0.1,0.15,_(0.2),0.3,0.4)were synthesized from solid-state reaction.The mechanoluminescence(ML)performance of Sr_(1.96)SnO_(4):0.04Sm^(3+)was greatly enhanced by partial Si^(4+)substitution for Sn^(4+),and the sample of Sr_(1.96)Sn_(0.8)Si_(0.2)O_(4):0.04Sm^(3+)showed weaker afterglow and twice stronger ML intensity than that in Sr_(1.96) SnO_(4):0.04Sm^(3+).The stress response of Sr_(1.96)Sn_(0.8)Si_(0.2)O_(4):0.04Sm^(3+)ranged from 250 to 1200 N,and its linearity was greatly restored.Particularly,it was very sensitive in the minimal stress response range.These properties of no load threshold for stress sensing and weak afterglow make Sr_(1.96)Sn_(0.8)Si_(0.2)O_(4):0.04Sm^(3+)superior to other excellent ML materials.The introduction of Si^(4+)caused lattice distortion and promoted defect formation in the system.The trap level energy greatly increased and the trap depth changed,which enhanced the trap ability and therefore improved effectively the ML properties.展开更多
We report that the co-doping of Li^(+)ions significantly enhances the crystallinity and mechanoluminescence(ML)intensity of CaZnOS:Mn.The prepared CaZnOS:Mn,Li showed a preferred orientation of c-axis,and the particle...We report that the co-doping of Li^(+)ions significantly enhances the crystallinity and mechanoluminescence(ML)intensity of CaZnOS:Mn.The prepared CaZnOS:Mn,Li showed a preferred orientation of c-axis,and the particles possessed a plate-like morphology,which could be attributed to the layered structure of CaZnOS.At the same time,the ML induced by compressive load exhibited intense red emission and obvious intensity enhancement by the Li^(+)co-doping.展开更多
This paper highlights our work on the recent progress in novel elastico-mechanoluminescence(EML)materials CaZnOS:Mn^(2+)and CaZr(PO_(4))_(2):Eu ^(2+),which can simultaneously"feel"(sense)and"see"(i...This paper highlights our work on the recent progress in novel elastico-mechanoluminescence(EML)materials CaZnOS:Mn^(2+)and CaZr(PO_(4))_(2):Eu ^(2+),which can simultaneously"feel"(sense)and"see"(image)the applied mechanical stress as an intense and proportional luminescence.CaZnOS:Mn 2þcan sense various types of mechanical stress,including ultrasonic vibration,impact,friction and compression because of the large piezoelectric coefficient.CaZr(PO_(4))_(2):Eu ^(2+)with multiple trap levels shows a broad measurement range for dynamic load.Both of CaZnOS:Mn^(2+)and CaZr(PO_(4))_(2):Eu ^(2+)belong to the defect-controlled type pie-zoelectric phosphors,and their EML mechanisms could be explained using the piezoelectrically induced carrier de-trapping model.展开更多
Visible light-based human–machine interactive media is capable of transmitting electrical readouts to machines and providing intuitive feedback to users simultaneously.Currently,many inorganic mechanoluminescent(ML)m...Visible light-based human–machine interactive media is capable of transmitting electrical readouts to machines and providing intuitive feedback to users simultaneously.Currently,many inorganic mechanoluminescent(ML)materials-based interactive media,typically ZnS-loaded phosphors(ZLPs),have been successfully demonstrated.However,organic ML materials-based solutions were rarely exploited despite their huge merits of strong structural modification,abundant luminescence property,low cost,easy preparation,and so on.Here,we propose a novel interactive tactile display(ITD)based on organic ML materials(Cz-A6-dye)and triboelectric nanogenerator,with ultra-brightness(130%enhancement)and ultra-low threshold pressure(57%reduction)as compared to ZLPs.The proposed ITD achieves the conversion of weak mechanical stimuli into visible light and electrical signals simultaneously,without extra power supplies.Furthermore,the relationship between the luminous performance of organic ML materials and mechanical force is quantified,benefiting from the uniform ML layer prepared.Enabled by convolutional neural networks,the high-accuracy recognition(97.1%)for handwriting and identity of users is realized at the same time.Thus,the ITD has great potential for intelligent wearable electronics and classified military applications.展开更多
Luminescent hydrogen-bonded organic frameworks(HOFs)have attracted increasing attention due to their corresponding luminescence that enables readily visualization of structural dynamics.HOFs with the mechanoluminescen...Luminescent hydrogen-bonded organic frameworks(HOFs)have attracted increasing attention due to their corresponding luminescence that enables readily visualization of structural dynamics.HOFs with the mechanoluminescence(ML)property can emit light without photon excitation and are greatly attractive for advanced applications,but research in this area has been limiting.Herein,we report the first example of an ML-active flexible HOF with permanent porosity,named 8PCOM,assembled from polar molecular rotors with an aggregation-induced emission property.When responding to different solvent vapors,reversible structural transformations between ML-active and-inactive 8PCOM frameworks occur,including a single-crystal-to-single-crystal(SCSC)transformation.Thus,vip-induced breathing behaviors are mainly attributed to phenyl rotations of polar molecular rotors induced by external stimuli.During reversible structural transformations of various 8PCOM frameworks with different pores,the significant ML property is achieved successfully through supramolecular dipole moment regulation.Upon mechanical force,bright emission of the ML-active 8PCOM framework is observed without UV irradiation,and the ML-active crystals can be easily prepared and regenerated.This work not only provides a valuable strategy for engineering future multifunctional HOFs but also enriches the types and applications of existing luminescent porous materials.展开更多
The complex wiring,bulky data collection devices,and difficulty in fast and on-site data interpretation significantly limit the practical application of flexible strain sensors as wearable devices.To tackle these chal...The complex wiring,bulky data collection devices,and difficulty in fast and on-site data interpretation significantly limit the practical application of flexible strain sensors as wearable devices.To tackle these challenges,this work develops an artificial intelligenceassisted,wireless,flexible,and wearable mechanoluminescent strain sensor system(AIFWMLS)by integration of deep learning neural network-based color data processing system(CDPS)with a sandwich-structured flexible mechanoluminescent sensor(SFLC)film.The SFLC film shows remarkable and robust mechanoluminescent performance with a simple structure for easy fabrication.The CDPS system can rapidly and accurately extract and interpret the color of the SFLC film to strain values with auto-correction of errors caused by the varying color temperature,which significantly improves the accuracy of the predicted strain.A smart glove mechanoluminescent sensor system demonstrates the great potential of the AIFWMLS system in human gesture recognition.Moreover,the versatile SFLC film can also serve as a encryption device.The integration of deep learning neural network-based artificial intelligence and SFLC film provides a promising strategy to break the“color to strain value”bottleneck that hinders the practical application of flexible colorimetric strain sensors,which could promote the development of wearable and flexible strain sensors from laboratory research to consumer markets.展开更多
Near-infrared(NIR)mechanoluminescent(ML)materials hold significant potential for nondestructive detection and biological stress imaging applications.However,practical implementation may be hindered by a narrow NIR ML ...Near-infrared(NIR)mechanoluminescent(ML)materials hold significant potential for nondestructive detection and biological stress imaging applications.However,practical implementation may be hindered by a narrow NIR ML bandwidth,dependence on ultraviolet preirradiation,and a high stress threshold.In this study,we develop a low-threshold broadband NIR ML material with self-recoverable characteristics by introducing Cr^(3+)into a simple and naturally abundant oxide host,MgO.The observed ML originates from the localized piezoelectricity effect induced by Cr^(3+)incorporation.The optimized MgO:0.008Cr^(3+)exhibits a predominant ML peak at 809 nm with a broad full width at half maximum of 209 nm.Notably,this material demonstrates high ML intensity and sensitivity,enabling detectable emission even under extremely low-stress conditions(1 N).Leveraging its bright and broadband NIR ML,MgO:Cr^(3+)is applied for nondestructive assessment of wine quality.Furthermore,a simulated biological stress imaging model was used to verify its superior tissue penetration ability.This study expands the library of self-recoverable NIR ML materials with broadband emission and offers valuable insights for advancing the practical utilization of NIR ML technologies.展开更多
基金Project supported by the State Key Research Projects of Shandong Natural Science Foundation (ZR2020KB019)the fund of "Two-Hundred Talent" Plan of Yantai City+1 种基金the National Natural Science Foundation of China(11974013)the Natural Science Foundation of Fujian Province (2022J011270)。
文摘X-ray irradiated La_(2)Ti_(2)O_(7):Pr^(3+)was found to show long-time sustainable mechanoluminescence(ML),which can realize the high sensitivity and real time detection of stress burst for more than 72 h.Under the excitation of X-ray,La_(2)Ti_(2)O_(7):Pr^(3+)shows red ML emissions located at 610,624 and 638 nm,which are similar to the afterglow emission spectrum and can be ascribed to(1)^D_(2)-^(3)H_(4),^(3)P_(0)-(3)^H_(4)and (3)^P_(0)-^(3)H_(2)of Pr^(3+).And the linear increases of compressive load can induce the linear increases of ML intensity of the sample,indicating that the X-ray induced ML emission can be utilized to accurately detect the stress applied on the object.Furthermore,X-ray irradiated La_(2)Ti_(2)O_(7):Pr^(3+)possesses excellent stability and the repeatability of ML emission and the ML signals can keep stable even 50 load cycles after 1 h dacay.The thermoluminescence results suggest that abundant electrons are trapped in shallow and deep answered for stable ML emission.More importantly,the deeply trapped electrons induced ML emissions from X-ray irradiated La_(2)Ti_(2)O_(7):Pr^(3+)can be utilized to detect the stress bursts for a long time.When the sample is recharged by 5 min X-ray irradiation once,within 24 h decay,the 1500 N burst among many 1000 N cycles can be clearly detected,and the signal to noise ratio(S/N) reaches 1.32 and 1.26 after 12 and24 h decay,respectively.And even after 72 h decay,the S/N of 2500 N still arrives at 1.23 and that of4000 N reaches 1.97,indicative of long-time high sensitivity detection of abnormal stress.All these results suggest that the X-ray-irradiated La_(1.97)Ti_(2)O_(7):0.03Pr^(3+)/resin sample can realize the high sensitivity and real time detection of stress burst for more than 72 h,which thus possesses great potential application in early warning of the emergency disasters such as bridge fracture,tunnel collapse and so on.
基金supported by the National Natural Science Foundation of China(52201008,52372003)Natural Science Foundation of Heilongjiang Province of China(ZD2023E004)+1 种基金Fundamental Research Funds for the Central Universities(3072020CF2515,3072022CFJ2504)the State Key Laboratory of Particle Detection and Electronics(SKLPDE-KF-202311)。
文摘Mechano luminescence(ML),which involves the emission of light under mechanical stimuli,shows great potential in various applications such as sensing,imaging,and energy harvesting.Current research suggests that the luminescence mechanism of ML is typically connected to specific defects present within the material.In this study,we focus on the investigation of ML defects in Pr^(3+)-doped NaNbO_(3)/LiNbO_(3)heterojunctions,employing a combination of experimental and theoretical approaches.Through experimental analysis,we confirmed the presence of the heterojunction and its influence on ML intensity,and the optimal doping ratio for the heterojunction in ML was established.Furthermore,we examined the influence of varying Pr^(3+)doping concentrations on ML behavior and a proof-of-concept was demonstrated using the X-rays charged heterostructural phosphor as a stress sensor for biological applications.The position and concentration of internal defects in the ML material were scrutinized through thermo luminescence tests employing the variable heating rate method and positron annihilation.Complementing the experimental findings,theoretical simulations were conducted to elucidate the underlying mechanisms responsible for the observed ML defects.Density functional theory calculations were employed to investigate the energy levels,charge transfer processes,and lattice distortions within the heterojunctions under mechanical stress.Theoretical predictions were compared and validated against the experimental results.The integration of experimental and theoretical approaches provides a comprehensive understanding of the ML behavior of Pr^(3+)-doped NaNbO_(3)/LiNbO_(3)heterojunctions.The insights gained from this research contribute to the development of novel ML materials and pave the way for their applications in next-generation sensing and energy conversion devices.
基金supported by the Department of Science and Technology of Zhejiang Province(2024C01192,2022C03098)Zhejiang Provincial Natural Science Foundation(LZ22E020001)the National Natural Science Foundation of China(62075204).
文摘Mechanoluminescence(ML)materials have shown tremendous application potential due to their luminescent properties stimulated by mechanical energy.Owing to the narrow awareness of alterations in the crystal field environment of materials,the ML performance optimization is severely restricted.Here,a novel strategy of doping Y^(3+)into SrAl_(2)-_(x)Y_(x)O_(4):Eu^(2+),Dy^(3+)phosphors was employed by solid-phase reaction,significantly improving the ML performance.Based on analysis of structure and luminescent properties,it is proved that Y^(3+)occupies Al^(3+)sites,causing lattice expansion and crystal field distortion,altering trap engineering,strengthening carrier de-trapping ability,and improving ML performance.Through thermo luminescence(TL)analysis,the brighter ML behavior can be attributed to the carriers recombination generated by high-density deep traps of 0.836 eV and above.Materials were also investigated in relation to pressure,stability and repeatability and conducive to achieving dynamic anticounterfeiting of personal signature.This study also provides more evidence that doping ions is an efficient tactic for greatly enhancing ML performance.
基金supported by the National Natural Science Foundation of China(12164034)the Natural Science Foundation of Inner Mongolia(2023LHMS01002)the Science and Technology Project of Shenzhen(JCYJ20220531102603007)。
文摘The gallate salts are frequently employed as matrix for mechanoluminescence(ML)materials largely due to their plentiful defect energy levels and robust piezoelectric characteristics.Nevertheless,the ML performance of specific gallate materials is inferior to that of sulfides and fluorides and thus requires improvement.To address this issue,it is essential to engineer appropriate lattice defects in order to facilitate the advancement of new elastic ML materials.Therefore,in the present study,a series of Ca_(3)Ga_(4)O_(9):0.01 Bi^(3+),xTb^(3+)(x=0.01,0.02,0.03,0.04,0.05 and 0.06)was synthesized using the traditional high-temperature solid-state method.Furthermore,a non-intrinsic defect control strategy utilising Bi^(3+)ions is presented,which serves to enhance the performance of calcium gallate.The ML intensity is enhanced by 112%in comparison to the undoped samples(concentration of Tb^(3+)is 0.04),resulting in an improved linearity between mechanical loading and ML intensity,along with the achievement of dualmode photoluminescence(PL).By analysing the crystal structure,PL,ML,and thermoluminescence(TL)properties of Ca_(3)Ga_(4)O_(9):Bi^(3+),Tb^(3+)(CGO:Bi^(3+),Tb^(3+)),coupled with the first principles calculations using density functional theory(DFT),the ML mechanism of CGO:Bi^(3+),Tb^(3+)was elucidated.This leads to the development of a versatile anti-counterfeiting device with both flexible and rigid multi-mode capabilities.
文摘Two new binuclear (europium and lanthanum) beta-diketone complexes Eu0.9La0.1(TTA)(3)Phen and Eu0.5La0.5(TTA)(3)Phen in which Phen is 1,10-phenanthroline, TTA is an anion of thenoyltrifluoroacetone (HTTA) were synthesized for the first time. They showed intense photoluminescence (PL) and mechanoluminescence (ML), and had their maximum PL and ML spectra peaked at 613.5 nm with half bandwidth of 10 nm respectively. Their PL and ML intensity were obviously stronger than these from Eu(TTA)(3)Phen. It is considered that binuclear (europium and lanthanum) beta-diketones complexes are promising ML and PL materials.
文摘A novel self-recoverable mechanoluminescent phosphor Ca_(5)Ga_(6)O_(14)∶Eu^(3+) was developed by the high-tem-perature solid-state reaction method,and its luminescence properties were investigated.Ca_(5)Ga_(6)O_(14)∶Eu^(3+)can produce red mechanoluminescence,and importantly,it shows good repeatability.The mechanoluminescence of Ca_(5)Ga_(6)O_(14)∶Eu^(3+) results from the piezoelectric field generated inside the material under stress,rather than the charge carriers stored in the traps,which can be confirmed by the multiple cycles of mechanoluminescence tests and heat treatment tests.The mechanoluminescence color can be turned from red to green by co-doping varied concentrations of Tb^(3+),which may be meaningful for encrypted letter writing.The encryption scheme for secure communication was devised by harnessing mechanoluminescence patterns in diverse shapes and ASCII codes,which shows good encryption performance.The results suggest that the mechanoluminescence phosphor Ca_(5)Ga_(6)O_(14)∶Eu^(3+),Tb^(3+)may be applied to the optical information encryption.
基金supported by the Natural Science Foundation of China(62275170)the Key-Area Research and Development Program of Guangdong Province(2024B0101080001)+4 种基金the Guangdong Provincial Science Fund for Distinguished Young Scholars(2022B1515020054)Shenzhen Fundamental Research Project(JCYJ20240813141624033)Scientific Research Foundation as Phase III construction of high-level University 2035 plan(0000050101)the proof-of-concept project of Shenzhen University(000003011313)as well as Medical-Engineering Interdisciplinary Research Foundation of ShenZhen University(2023YG031).
文摘During the downconversion process,a high-energy photon undergoes conversion into several low-energy photons,leading to enhanced luminous efficiency in both photoluminescent and electroluminescent devices.This phenomenon has been applied in various fields,including solar cells,plasma display panels,and green lighting technologies such as mercury-free fluorescent lamps.However,the concept of downconversion(quantum cutting)has not been fully explored in the context of mechanoluminescent materials.In this study,we successfully synthesized a heterojunction of CaF_(2)/CaZnOS exhibiting efficient downconversion mechanoluminescence(ML)properties.By controlling the CaF_(2)to CaZnOS ratio and incorporating Tb^(3+)doping,we obtained a highly effective heterojunction structure that significantly enhanced ML.Moreover,we extended this material to several commonly utilized downconversion ion-doping combinations,achieving enhanced ML for Tb^(3+),Pr^(3+),and Yb^(3+)single ions.For the first time,we demonstrate the downconversion(quantum cutting)ML of Tb^(3+)-Yb^(3+)and Pr^(3+)-Yb^(3+)pairs within heterojunction microstructures.This study presents the design and synthesis of a novel heterojunction material capable of realizing downconversion ML,which holds promise for future applications in diverse fields.
基金supported by the National Natural Science Foundation of China(52172001)Guangxi Natural Science Foundation(2022GXNSFDA035082)+3 种基金the Central Government Guided Local Science and Technology Development Fund Project(ZY22096009)the Guangxi Key Laboratory of Information Materials(Guilin University of Electronic Technology,Project No.211006-Z)the Innovation Project of GUET Graduate Education(2024YCXB03)the Program for Bagui Scholars of Guangxi,China.
文摘In this study,we investigated a novel multifunctional piezoelectric phosphor LiNbO_(3):1%Pr^(3+),0.5%Zn^(2+),which exhibited outstanding mechanoluminescence(ML)characteristics due to the strategic incorporation of Zn^(2+).A dual-regulation mechanism is proposed by adjusting the charge transfer band(CTB)energy level position and optimizing the defect distribution,thus realizing high-brightness,long-term storage,and highly repeatable red emission in ML.The addition of Zn^(2+)can lower the CTB energy level of the phosphor,which leads to the easier transfer of^(3)P_(0)electrons of Pr^(3+)to the^(1)D_(2)energy level through the CTB band,thus enhancing the ML red emission.The introduction of a small amount of Zn^(2+)effectively couple the trap structure with the piezoelectric properties of the material,significantly enhancing ML properties.Notably,the material exhibits excellent ML repeatability and long-term storage,maintaining a strong ML response even after 30 d.Density functional theory calculations of the phosphor confirmed that the doping of Zn^(2+)in LiNbO_(3):1%Pr^(3+)optimized the trap concentration and distribution,thereby improving the ML performance.This multifunctional material holds great potential for use in electromechanical and optoelectronic devices,contributing to the development of smart devices with broader applications.
基金supported by the National Natural Science Foundation of China(22463010,22063008)the National Natural Science Foundation of China(62275170)+9 种基金the Natural Science Foundation of Ningxia(2023AAC03227,2022AAC05002,2023AAC03183)the Project of Central Government Guides Local Science and Technology Development(2024FRD05053)the Key Research and Development Project of Ningxia(2023BEG03031)the Young Top-notch Talent Cultivation Program of Ningxiathe Discipline Project of Ningxia(NXYLXK2017A04)the support of Key-Area Research and Development Program of Guangdong Province(2024B0101080001)the Guangdong Provincial Science Fund for Distinguished Young Scholars(2022B1515020054)the Scientific Research Foundation as PhaseⅢConstruction of High-level University 2035 Plan(0000050101)the Proof-of-concept Project(000003011313)of Shenzhen Universitythe Medical-Engineering Interdisciplinary Research Foundation of Shenzhen University(2023YG031)。
文摘Investigation of luminescent materials with efficient photoluminescence(PL)and mechanoluminescence(ML)is significant for the development of both basic theories and industrial applications for new light sources,pressure sensors,and information security.In this study,we obtain a pair of isomorphic europium(Eu)^(3+)-containing coordination polymers(CPs),namely,[Eu(tfpd)_(3)(phen)]_(n)(1)and[Eu(tfpd)_(3)(bipy)]_(n)(2)(tfpd=4,4,4-trifluoro-4-pyridyl-1,3-diketonate,phen=1,10-phenanthroline,bipy=2,2'-bipyridine),which exhibit novel helical chain-like structures that can be extended to 3D supramolecular networks through moderate interchain interactions.The thermostable CPs simultaneously exhibit strong photoluminescence(PL)emissions with high quantum yields and excellent mechanoluminescence(ML)activity with an unusual anti-thermal quenching effect.Careful analyses of the CP crystal structures and optical performances,coupled with theoretical calculations,demonstrate that the PL emission depends on the asymmetric Eu^(3+)coordination spheres,whereas the ML activity is significantly correlated with molecular packing derived from appropriate interchain H-bonding interactions.As these CPs have highly efficient optical activities,they have promising potential applications in pressure sensing,anti-counterfeiting,and fingerprint recognition technologies.
基金the National Natural Science Foundation of China (Nos.11674318, 11774346, 5187228& and 51472242)the National Key R&D Program of China (No. 2016YFB0701003)the Chunmiao Project of the Haixi Institute of the Chinese Academy of Sciences (No.CMZX-2017-002).
文摘In this work,we discovered an unexpected mechanoluminescence (ML) phenomena occurring when transforming amorphous into crystalline,due to the stress-induced precipitation of CsPbBr3 perovskite nanocrystals on glass surface.It is revealed that,unlike the conventional thermal-induced phase transformation mechanism,the breakage of bonding of glass network provides the energy for nucleation and growth,and the shear stress avoids the long-range migration of structural units for crystallization.Such unique ML phenomenon enables the visualization of dynamical force that is inaccessible by common strategy,and so,opens up some novel applications,such as the pressure-sensitive "glassy pencil" to learn people's writing habits,and the pb^2+-detection with good sensitivity and selectivity.These findings not only demonstrate an effective route for the preparation of perovskite materials in a green,time-saving,low cost,and scalable way,enrich the knowledge of glass crystallization mechanism,but also exploit a useful avenue to quantitatively visualize the dynamical force.
基金supported by the National Natural Science Foundation of China(21905197)the Starting Grants of Tianjin University and Tianjin Government。
文摘A phenothiazine derivative PtzChol containing non-conjugated chiral cholesterol group was designed and synthesized. By analyzing the single crystal structure of PtzChol carefully, coupled with the circular dichroism(CD) signals before and after grinding, it was found that the introduction of cholesterol produced a positive effect on the production of chiral space group, on mechanoluminescence(ML) and room temperature phosphorescence(RTP), and throughout the entire light-emitting process, the CD signal could well reflect the changes of molecular arrangement.
基金This work was partly supported by a Grant-in-Aid for Scientific Research(A)(Grant number:25249100)from the Japan Society for the Promotion of Science.
文摘This article reports a new phosphorescent material,CaZnOS:Cu,that exhibits two types of mechano-optical conversion:mechanical quenching and mechanoluminescence.An intense mechanical quenching of phosphorescence corresponding to mechanical stimuli can be achieved in CaZnOS:Cu within a short decay time period.Over time,it gradually changes to mechanoluminescence when a mechanical load is applied.We propose that the mechanical quenching and mechanoluminescence arise from the different roles of shallow and deep traps in CaZnOS:Cu.CaZnOS:Cu has promising applications in monitoring mechanical stress in industrial plants,structures,and living bodies.
基金the National Natural Science Foundation of China(51832005)。
文摘Metal-organic frameworks(MOFs)and mechanoluminescent(ML)materials have been considered as two types of promising materials that have their own application fields.It would be amazing to endow one material with the advantages of ML and MOFs,thus broadening their applications.However,there are quite few investigations on this topic,and the ML mechanism in ML-MOFs remains unclear.In this study,we proposed a strategy for developing ML-MOFs by doping lanthanide ions into the non-centrosymmetric SBD([Sr(μ-BDC)(DMF)]∞)MOF,and successfully synthesized a series of lanthanide-doped MOFs Ln-SBD(Ln=Tb,Dy,Sm,Eu)and Tb1-xEux-SBD(x=0.2,0.4,0.6,0.8)with multicolor ML.The lanthanide ions were uniformly distributed in the matrix of the SBD-MOF,and occupied the Sr site.The MLMOFs exhibited intense multicolor ML emissions varying from green to yellow to red by changing the co-doping ratios and species of lanthanide ions.The similar ML and photoluminescence(PL)spectra indicated that the ML emission was assigned to the radiative transition from the excited states to the ground states of lanthanide ions.The radiative transition was induced by the electron bombardment process that originated from the piezoelectric effect of the non-centrosymmetric SBD host.In addition,a pioneering temperature sensing research based on ML was carried out,which is promising for realizing dual-functional detection of stress and temperature without excitation light sources.This study gives a unique insight for developing more versatile and interesting smart materials by combining the versatility of MOF with the ML emission,imparting additional values to both MOF and ML materials.Moreover,this study provides a general rule for selecting MOFs with an acentric structure as the host for ML materials.
文摘A series of Sr_(1.96)Sn_(1-x)Si_(x)O_(4):0.04Sm^(3+)(x=0,0.1,0.15,_(0.2),0.3,0.4)were synthesized from solid-state reaction.The mechanoluminescence(ML)performance of Sr_(1.96)SnO_(4):0.04Sm^(3+)was greatly enhanced by partial Si^(4+)substitution for Sn^(4+),and the sample of Sr_(1.96)Sn_(0.8)Si_(0.2)O_(4):0.04Sm^(3+)showed weaker afterglow and twice stronger ML intensity than that in Sr_(1.96) SnO_(4):0.04Sm^(3+).The stress response of Sr_(1.96)Sn_(0.8)Si_(0.2)O_(4):0.04Sm^(3+)ranged from 250 to 1200 N,and its linearity was greatly restored.Particularly,it was very sensitive in the minimal stress response range.These properties of no load threshold for stress sensing and weak afterglow make Sr_(1.96)Sn_(0.8)Si_(0.2)O_(4):0.04Sm^(3+)superior to other excellent ML materials.The introduction of Si^(4+)caused lattice distortion and promoted defect formation in the system.The trap level energy greatly increased and the trap depth changed,which enhanced the trap ability and therefore improved effectively the ML properties.
基金This work was also partly supported by Grant-in-Aid for Scientific Research(A)(Grant number:25249100)from Japan Society for the Promotion of Science.
文摘We report that the co-doping of Li^(+)ions significantly enhances the crystallinity and mechanoluminescence(ML)intensity of CaZnOS:Mn.The prepared CaZnOS:Mn,Li showed a preferred orientation of c-axis,and the particles possessed a plate-like morphology,which could be attributed to the layered structure of CaZnOS.At the same time,the ML induced by compressive load exhibited intense red emission and obvious intensity enhancement by the Li^(+)co-doping.
基金This work was supported by Shandong Provincial Natural Science Foundation,China(ZR2013EMQ003)Program of Science and Technology in Qingdao City(13-1-4-195-jch)CREST program of JST.
文摘This paper highlights our work on the recent progress in novel elastico-mechanoluminescence(EML)materials CaZnOS:Mn^(2+)and CaZr(PO_(4))_(2):Eu ^(2+),which can simultaneously"feel"(sense)and"see"(image)the applied mechanical stress as an intense and proportional luminescence.CaZnOS:Mn 2þcan sense various types of mechanical stress,including ultrasonic vibration,impact,friction and compression because of the large piezoelectric coefficient.CaZr(PO_(4))_(2):Eu ^(2+)with multiple trap levels shows a broad measurement range for dynamic load.Both of CaZnOS:Mn^(2+)and CaZr(PO_(4))_(2):Eu ^(2+)belong to the defect-controlled type pie-zoelectric phosphors,and their EML mechanisms could be explained using the piezoelectrically induced carrier de-trapping model.
基金HKSAR Research Grants Council,Grant/Award Numbers:16305320,C6014-20W,16307020,14200120National Natural Science Foundation of China,Grant/Award Numbers:21788102,52275560+3 种基金Guangdong Natural Science Funds for Distinguished Young Scholar,Grant/Award Number:2023B1515020074Innovation and Technology Commission,Grant/Award Number:ITCCNERC14SC01the start-up fund of Hong Kong University of Science and Technology(Guangzhou),Grant/Award Number:G0101000092the Project of Hetao Shenzhen-Hong Kong Science and Technology Innovation Cooperation Zone,Grant/Award Number:HZQB-KCZYB-2020083。
文摘Visible light-based human–machine interactive media is capable of transmitting electrical readouts to machines and providing intuitive feedback to users simultaneously.Currently,many inorganic mechanoluminescent(ML)materials-based interactive media,typically ZnS-loaded phosphors(ZLPs),have been successfully demonstrated.However,organic ML materials-based solutions were rarely exploited despite their huge merits of strong structural modification,abundant luminescence property,low cost,easy preparation,and so on.Here,we propose a novel interactive tactile display(ITD)based on organic ML materials(Cz-A6-dye)and triboelectric nanogenerator,with ultra-brightness(130%enhancement)and ultra-low threshold pressure(57%reduction)as compared to ZLPs.The proposed ITD achieves the conversion of weak mechanical stimuli into visible light and electrical signals simultaneously,without extra power supplies.Furthermore,the relationship between the luminous performance of organic ML materials and mechanical force is quantified,benefiting from the uniform ML layer prepared.Enabled by convolutional neural networks,the high-accuracy recognition(97.1%)for handwriting and identity of users is realized at the same time.Thus,the ITD has great potential for intelligent wearable electronics and classified military applications.
基金the National Natural Science Foundation of China(grant nos.51733010,51973239,and 52073316)the Science and Technology Planning Project of Guangdong(grant nos.2015B090913003 and 2015B090915003).
文摘Luminescent hydrogen-bonded organic frameworks(HOFs)have attracted increasing attention due to their corresponding luminescence that enables readily visualization of structural dynamics.HOFs with the mechanoluminescence(ML)property can emit light without photon excitation and are greatly attractive for advanced applications,but research in this area has been limiting.Herein,we report the first example of an ML-active flexible HOF with permanent porosity,named 8PCOM,assembled from polar molecular rotors with an aggregation-induced emission property.When responding to different solvent vapors,reversible structural transformations between ML-active and-inactive 8PCOM frameworks occur,including a single-crystal-to-single-crystal(SCSC)transformation.Thus,vip-induced breathing behaviors are mainly attributed to phenyl rotations of polar molecular rotors induced by external stimuli.During reversible structural transformations of various 8PCOM frameworks with different pores,the significant ML property is achieved successfully through supramolecular dipole moment regulation.Upon mechanical force,bright emission of the ML-active 8PCOM framework is observed without UV irradiation,and the ML-active crystals can be easily prepared and regenerated.This work not only provides a valuable strategy for engineering future multifunctional HOFs but also enriches the types and applications of existing luminescent porous materials.
基金funded by the National Natural Science Foundation of China(52475580)the Special Foundation of the Taishan Scholar Project(tsqn202211077,tsqn202311077)+3 种基金Shandong Provincial Excellent Overseas Young Scholar Foundation(2023HWYQ-069)the Shandong Provincial Natural Science Foundation(ZR2023ME118,ZR2023QF080)the Natural Science Foundation of Qingdao City(23-2-1-219-zyyd-jch,23-2-1-111-zyyd-jch)the Fundamental Research Funds for the Central Universities(23CX06032A).
文摘The complex wiring,bulky data collection devices,and difficulty in fast and on-site data interpretation significantly limit the practical application of flexible strain sensors as wearable devices.To tackle these challenges,this work develops an artificial intelligenceassisted,wireless,flexible,and wearable mechanoluminescent strain sensor system(AIFWMLS)by integration of deep learning neural network-based color data processing system(CDPS)with a sandwich-structured flexible mechanoluminescent sensor(SFLC)film.The SFLC film shows remarkable and robust mechanoluminescent performance with a simple structure for easy fabrication.The CDPS system can rapidly and accurately extract and interpret the color of the SFLC film to strain values with auto-correction of errors caused by the varying color temperature,which significantly improves the accuracy of the predicted strain.A smart glove mechanoluminescent sensor system demonstrates the great potential of the AIFWMLS system in human gesture recognition.Moreover,the versatile SFLC film can also serve as a encryption device.The integration of deep learning neural network-based artificial intelligence and SFLC film provides a promising strategy to break the“color to strain value”bottleneck that hinders the practical application of flexible colorimetric strain sensors,which could promote the development of wearable and flexible strain sensors from laboratory research to consumer markets.
基金supported by the National Natural Science Foundation of China(12374372,52372134)the Fundamental Research Funds for the Provincial Universities of Zhejiang(GK259909299001-043)the Zhejiang Provincial Natural Science Foundation of China(LQN25E020010)。
文摘Near-infrared(NIR)mechanoluminescent(ML)materials hold significant potential for nondestructive detection and biological stress imaging applications.However,practical implementation may be hindered by a narrow NIR ML bandwidth,dependence on ultraviolet preirradiation,and a high stress threshold.In this study,we develop a low-threshold broadband NIR ML material with self-recoverable characteristics by introducing Cr^(3+)into a simple and naturally abundant oxide host,MgO.The observed ML originates from the localized piezoelectricity effect induced by Cr^(3+)incorporation.The optimized MgO:0.008Cr^(3+)exhibits a predominant ML peak at 809 nm with a broad full width at half maximum of 209 nm.Notably,this material demonstrates high ML intensity and sensitivity,enabling detectable emission even under extremely low-stress conditions(1 N).Leveraging its bright and broadband NIR ML,MgO:Cr^(3+)is applied for nondestructive assessment of wine quality.Furthermore,a simulated biological stress imaging model was used to verify its superior tissue penetration ability.This study expands the library of self-recoverable NIR ML materials with broadband emission and offers valuable insights for advancing the practical utilization of NIR ML technologies.
