Under the condition of solvothermal synthesis,the viologen ligand 1,1′-bis(3-carboxyphenyl)-(4,4′-bipyri-dine)dichloride(H_(2)bcbpy·2Cl)and KI are coordinated with the metal cadmium ions.A case of thermochromic...Under the condition of solvothermal synthesis,the viologen ligand 1,1′-bis(3-carboxyphenyl)-(4,4′-bipyri-dine)dichloride(H_(2)bcbpy·2Cl)and KI are coordinated with the metal cadmium ions.A case of thermochromic coor-dination polymer[Cd(bcbpy)I_(2)]·2H_(2)O(1)was constructed.Complex 1 displays a 1D chain structure and exhibits thermochromic behavior.Under different temperature stimulation,the complex(ground)slowly changed from green to yellow-green,and with the increase of temperature,the color of complex 1 gradually deepened,and finally became orange-yellow.Therefore,complex 1 was prepared as a thermochromic film.In addition,we also performed electrochemical tests on complex 1,which showed that the complex is a semiconductor material.CCDC:2391802.展开更多
We report a facile approach to water-dispersible polydiacetylene/rare earth ions nanocomposites with reversible thermochromism. The nanocomposites were prepared by doping rare earth ions Dy^3＋ or Sin^3＋ into layer-s...We report a facile approach to water-dispersible polydiacetylene/rare earth ions nanocomposites with reversible thermochromism. The nanocomposites were prepared by doping rare earth ions Dy^3＋ or Sin^3＋ into layer-structured 10,12-pentacosadiynoic acid （PCDA） nanopar- ticles to obtain PCDA/rare earth ions nanocomposites （PCDA-RE） and subsequently annealing PCDA-RE at the temperature slightly higher than the melting point of pure PCDA crystals, followed by topochemically polymerizing the annealed PCDA-RE. The polymerized PCDA-RE, i.e. poly（10,12-pentacosadiynoic acid）/rare earth ions nanocomposites （PDARE： PDA-Dy or PDA-Sm）, are largely reversible （PDA-Sm） or even completely reversible （PDA-Dy） in the thermochromism, while, without the doping, pure PDA is completely irreversible. It is confirmed that, PDA-RE are also layer-structured with a d-spacing of 5.4 nm, higher than the d-spacing of pure PDA （4.7 nm）. In PDA-RE, the rare earth ions form a layer in-between and interact strongly with the PDA bilayers, being responsible for the high degree or even the complete reversibility. This is the first example to make PDA completely reversible through the doping of rare earth ions; the annealing process is essential for the complete reversibility since it removes any defects in the structure.展开更多
The highly integrated and miniaturized next-generation electronic products call for high-performance electromagnetic interference(EMI)shielding materials to assure the normal operation of their closely assembled compo...The highly integrated and miniaturized next-generation electronic products call for high-performance electromagnetic interference(EMI)shielding materials to assure the normal operation of their closely assembled components.However,the most current techniques are not adequate for the fabrication of shielding materials with programmable structure and controllable shielding efficiency.Herein,we demonstrate the direct ink writing of robust and highly conductive Ti3C2Tx MXene frames with customizable structures by using MXene/AlOOH inks for tunable EMI shielding and electromagnetic wave-induced thermochromism applications.The as-printed frames are reinforced by immersing in AlCl_(3)/HCl solution to remove the electrically insulating AlOOH nanoparticles,as well as cross-link the MXene sheets and fuse the filament interfaces with aluminum ions.After freeze-drying,the resultant robust and porous MXene frames exhibit tunable EMI shielding efficiencies in the range of 25-80 dB with the highest electrical conductivity of 5323 S m−1.Furthermore,an electromagnetic wave-induced thermochromic MXene pattern is assembled by coating and curing with thermochromic polydimethylsiloxane on a printed MXene pattern,and its color can be changed from blue to red under the high-intensity electromagnetic irradiation.This work demonstrates a direct ink printing of customizable EMI frames and patterns for tuning EMI shielding efficiency and visualizing electromagnetic waves.展开更多
Using 1,1-bis(isoquinoline)-1,4-phenyldimethylenyl(BIQPM^(2+))cation as template,a new tetrameric(Bi_(4)I_(16))^(4-)-iodobismuthate-containing hybrid with formula of(BIQPM)_(2)(Bi_(4)I_(16)·H_(2)O(1),has been pre...Using 1,1-bis(isoquinoline)-1,4-phenyldimethylenyl(BIQPM^(2+))cation as template,a new tetrameric(Bi_(4)I_(16))^(4-)-iodobismuthate-containing hybrid with formula of(BIQPM)_(2)(Bi_(4)I_(16)·H_(2)O(1),has been prepared under solvothermal conditions.The centrosymmetric (Bi_(4)I_(16))^(4- ) tetraanion is constructed from four edge-shared slightly distorted BiI6 octahedrons.Due to the presence of larger conjugated system(isoquinoline ring),strongπ···πstacking interactions can be observed.Besides,strong I···I interactions can be monitored and extends the 0-D (Bi_(4)I_(16))^(4- )cluster to a quasi-1-D chain.The smaller energy gap of 2.13 eV is led by these non-covalent interactions.Its infrared emission might be caused by strong charge transfer between anions and cations.Furthermore,the reversible thermochromic behavior with low chromotropic temperature of 80℃can be observed,whose mechanism was discussed.展开更多
Three kinds of thermochromic materials(DC8,DC12,DC16)were synthesized by linking the rigid 1,4-bis[2-(4-pyridyl)ethenyl]-benzene(bpeb)with different lengths of alkyl chains.They exhibit remarkable fluorescent color ch...Three kinds of thermochromic materials(DC8,DC12,DC16)were synthesized by linking the rigid 1,4-bis[2-(4-pyridyl)ethenyl]-benzene(bpeb)with different lengths of alkyl chains.They exhibit remarkable fluorescent color changes under the irradiation of 365 nm light with elevating temperature,which is supposed to be caused by the transition between the crystal state and the amorphous state.Interestingly,the DC16 solid also has a photochromic character.It should be noticed that the phase transition temperatures of three materials measured by differential scanning calorimetry are higher than those of the fluorescence color changes during the heating process.Thus,the allochroic effect is attributed to the synergistic effect of both heating and photo-inducement(365 nm).Ethanol can turn the heated powder into the initial crystal again which indicates that their thermochromic behavior is reversible and makes the fluorescence recover.展开更多
By leveraging the unique qualities of microorganisms,engineered living materials(ELMs)offer functional and economic advantages in everyday applications along with notable ecological benefits.This study contributes to ...By leveraging the unique qualities of microorganisms,engineered living materials(ELMs)offer functional and economic advantages in everyday applications along with notable ecological benefits.This study contributes to the growing field of biodesign by examining the potential of Flavobacteria for thermochromic ELMs.Many Flavobacteria,commonly found in marine environments,produce iridescent structural colorations as their colonies expand on semi-solid surfaces through gliding motility.In this study,we analyzed the effects of temperature variations on flavobacterium Cellulophaga lytica PLY A 2,characterizing distinct changes in colony growth and iridescent colorations at a macroscopic and microscopic scale.Using scanning electron microscopy,we investigated the relationship between iridescent color and the underlying cell-based optical structures.By providing insights into the temperature-responsive behavior of Flavobacteria,our findings highlight their potential for future thermochromic ELMs-with applications ranging from sustainable food packaging to smart textiles-while encouraging further characterization studies within biodesign research.展开更多
Since the discovery of the triphenylmethyl(trityl)cation 120 years ago,a variety of aromatic cations having various colors and luminescence properties have been rigorously studied.Many,differently substituted trityl c...Since the discovery of the triphenylmethyl(trityl)cation 120 years ago,a variety of aromatic cations having various colors and luminescence properties have been rigorously studied.Many,differently substituted trityl cations have been synthesized,and their optical properties have been elucidated.However,the optical properties of the parent,non-substituted and highly reactive trityl cation,which was observed to be very weakly luminescent,have not been subjected to detailed investigation.In the effort described herein,we explored the optical nature of non-substituted trityl hexafluorophosphate(PF_(6))in the crystalline state.Trityl PF_(6) was found to exist as two crystal polymorphs including a yellow(Y)and an orange(O)form.Moreover,we observed that these crystalline forms display crystalline-state emission with different colors.The results of X-ray crystallographic analysis showed that the two polymorphs have totally different molecular packing arrangements.Furthermore,an investigation of their optical properties revealed that the O-crystal undergoes a distinct color change to yellow upon cooling as a consequence of a change in the nature of the charge transfer interaction between the cation and PF6 anion,and that both the Y-and O-crystal exhibit phosphorescence.展开更多
Stimuli-responsive luminescent switching materials with multifunctional properties are highly essential for advanced photonic applications,yet achieving such capabilities in halide perovskites continues to pose a sign...Stimuli-responsive luminescent switching materials with multifunctional properties are highly essential for advanced photonic applications,yet achieving such capabilities in halide perovskites continues to pose a signif-icant challenge.In this work,we explore a new water-stimuli-responsive zero-dimensional(0D)Sb-based halide of[PhPz]_(2)SbCl_(7)·2H_(2)O(PhPz=phenylpiperazine),which consists of isolated[SbCl_(6)]^(3-) octahedra in[PhPz]2+cationic matrix with vip H_(2)O molecules.Under UV excitation,[PhPz]_(2)SbCl_(7)·2H_(2)O emits intense broadband red light with maximum emission at 645 nm,and combined optical characterization and theoretical calculations confirm that this luminescence originates from self-trapped excitons(STEs).Interestingly,the free water molecules can reversibly leave and entry the crystal lattice during heating-cooling cycles accompanied by the formation of dehydrated phase,which displays strong yellow emission with maximum peak at 580 nm.Therefore,reversible luminescent switching between red and yellow emission is achieved through controllable removal and adsorption process of vip H_(2)O.By virtue of this reversible thermochromic switching,this halide can be used to detect the trace amount of water in various organic solvents and humidity of moist air.In addition,such switchable dual emission further realizes application in anti-counterfeiting and information encryption-decryption.This work deepens the understanding of structure-property relationships and expands the application range of oD metal halides.展开更多
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
Thermochromic materials based on solid-state oxides exhibit many potential photo-thermal regulation applications.Herein,we report a new thermochromic pure-phase CaCrO_(4) pigment with merits of high chromatic aberrati...Thermochromic materials based on solid-state oxides exhibit many potential photo-thermal regulation applications.Herein,we report a new thermochromic pure-phase CaCrO_(4) pigment with merits of high chromatic aberration,fully reversible thermochromism,and high stability.CaCrO_(4) crystalized into a tetragonal zircon-type structure,which showed a successively reversible color change from greenish yellow to reddish orange with the highest chromatic aberration (ΔE^(*)_(CIE)) of 59.60.In situ variable temperature X-ray diffraction analysis results revealed that the expansion of the lattice was uniaxial along the c-axis with a dilation rate of 2.06×10^(−5),while that along the a-axis remained nearly unchanged in the temperature range of 25–575℃.In situ variable temperature UV–vis absorption spectra of CaCrO_(4) revealed a successive bandgap reduction with an average temperature dependency rate(dE_(g)/dT)_(aver age) of 0.27 meV K^(−1).Continuous color change or bandgap reduction originated from the successive elongation of Cr–O bonds in the CrO_(4) tetrahedral chromophore in the lattice.The most sensitive temperature range was between 175℃ and 400℃,which rendered a naked-eye-detection accuracy rate of over 85%for a standard temperature deviation(ΔT)of 25℃,demonstrating the potential of the pigment as a pan-bottom temperature indicator for healthy cooking.展开更多
All-season thermal management with zero energy consumption and emissions is more crucial to global decarbonization over traditional energy-intensive cooling/heating systems.However,the static single thermal management...All-season thermal management with zero energy consumption and emissions is more crucial to global decarbonization over traditional energy-intensive cooling/heating systems.However,the static single thermal management for cooling or heating fails to self-regulate the temperature in dynamic seasonal temperature condition.Herein,inspired by the dual-temperature regulation function of the fur color changes on the backs and abdomens of penguins,a smart thermal management composite hydrogel(PNA@H-PM Gel)system was subtly created though an"on-demand"dual-layer structure design strategy.The PNA@H-PM Gel system features synchronous solar and thermal radiation modulation as well as tunable phase transition temperatures to meet the variable seasonal thermal requirements and energy-saving demands via self-adaptive radiative cooling and solar heating regulation.Furthermore,this system demonstrates superb modulations of both the solar reflectance(ΔR=0.74)and thermal emissivity(ΔE=0.52)in response to ambient temperature changes,highlighting efficient temperature regulation with average radiative cooling and solar heating effects of 9.6℃in summer and 6.1℃in winter,respectively.Moreover,compared to standard building baselines,the PNA@H-PM Gel presents a more substantial energy-saving cooling/heating potentials for energy-efficient buildings across various regions and climates.This novel solution,inspired by penguins in the real world,will offer a fresh approach for producing intelligent,energy-saving thermal management materials,and serve for temperature regulation under dynamic climate conditions and even throughout all seasons.展开更多
Photothermoelectric(PTE)photodetectors with selfpowered and uncooled advantages have attracted much interest due to the wide application prospects in the military and civilian fields.However,traditional PTE photodetec...Photothermoelectric(PTE)photodetectors with selfpowered and uncooled advantages have attracted much interest due to the wide application prospects in the military and civilian fields.However,traditional PTE photodetectors lack of mechanical flexibility and cannot operate independently without the test instrument.Herein,we present a flexible PTE photodetector capable of dual-mode output,combining electrical and optical signal generation for enhanced functionality.Using solution processing,high-quality MXene thin films are assembled on asymmetric electrodes as the photosensitive layer.The geometrically asymmetric electrode design significantly enhances the responsivity,achieving 0.33 m A W^(-1)under infrared illumination,twice that of the symmetrical configuration.This improvement stems from optimized photothermal conversion and an expanded temperature gradient.The PTE device maintains stable performance after 300 bending cycles,demonstrating excellent flexibility.A new energy conversion pathway has been established by coupling the photothermal conversion of MXene with thermochromic composite materials,leading to a real-time visualization of invisible infrared radiation.Leveraging this functionality,we demonstrate the first human-machine collaborative infrared imaging system,wherein the dual-mode photodetector arrays synchronously generate human-readable pattern and machine-readable pattern.Our study not only provides a new solution for functional integration of flexible photodetectors,but also sets a new benchmark for human-machine collaborative optoelectronics.展开更多
Correction for‘A new methylviologen-templated zinc gallophosphate zeolite with photo-/thermochromism,fluorescent and photoelectric properties’by Chunyao Tao,et al.,Inorg.Chem.Front.,2016,DOI:10.1039/c5qi00283d.
A new zinc gallophosphate zeolite[Zn_(5.8)Ga_(14.2)(PO_(4))_(2)0F_(3.2)(H_(3)O)_(3)]|C_(12)H_(14)N_(2)|_(3)·3H_(2)O(noted as JU104)with a USI zeotype structure has been solvothermally synthesized by using in situ...A new zinc gallophosphate zeolite[Zn_(5.8)Ga_(14.2)(PO_(4))_(2)0F_(3.2)(H_(3)O)_(3)]|C_(12)H_(14)N_(2)|_(3)·3H_(2)O(noted as JU104)with a USI zeotype structure has been solvothermally synthesized by using in situ generated methylviologen(MV)as the template.JU104 has two-dimensional interconnected 12-ring and 10-ring channels running along the[100]and[010]direction,respectively.It exhibits dual thermochromism and photochromism with a broad photo-response range(UV light to visible light)and a long-lived charge-separated state,as well as variable fluorescent and photoelectric properties.Moreover,the multi photo/thermo-induced colors occurring in JU104 make it unusual as compared to other inorganic photo/thermochromism compounds.The MV-templated JU104 zeolite may function as a new efficient electron-transfer system for potential applications in photo/thermochromism and solar energy conversion.展开更多
A transient measurement technique by using narrow-band thermochromic liquid crystal （TLC） is employed to determine temperature and heat transfer coefficient （HTC） distribution on inner surfaces of the typical lami...A transient measurement technique by using narrow-band thermochromic liquid crystal （TLC） is employed to determine temperature and heat transfer coefficient （HTC） distribution on inner surfaces of the typical lamilloy configurations. With this technique, both local HTC distribution and average HTC distribution could be obtained. The experimental results indicate that the variation of the porosity ratio, the one that the area of impingement holes divided by that of the plate, has a great effect on the HTC distribution on the inner surfaces. Heat exchange of inner surfaces varies directly as the porosity ratio. The impingement Reynolds number ranges from 20 000 to 50 000. The average HTC of inner surfaces bears a linear relationship with the Reynolds number.展开更多
Thermochromic polymers will play an extremely important role in the next future. The physical background of thermochromism and the state of development of thermochromic polymers based on light absorption effects are r...Thermochromic polymers will play an extremely important role in the next future. The physical background of thermochromism and the state of development of thermochromic polymers based on light absorption effects are reported. In detail, the interactions between the polymer matrix and the thermochromic composite - composed of leuco or indicator dyes - are discussed on a molecular level. Thermochromic hydrogels with extremely high transparency, an outstanding switching behavior from colorless to colored or between different colors is presented. Preparation of thermosetting and thermoplastic polymers, including the resulting optical, and, for the first time, the mechanical properties are discussed in relation to matrix tuned high-resistant microcapsules.展开更多
Functional materials may change color by heat and electricity separately or simultaneously in smart windows.These materials have not only demonstrated remarkable potential in the modulation of solar radiation but are ...Functional materials may change color by heat and electricity separately or simultaneously in smart windows.These materials have not only demonstrated remarkable potential in the modulation of solar radiation but are also leading to the development of indoor environments that are more comfortable and conducive to improving individuals'quality of life.Unfortunately,dual-responsive materials have not received ample research attention due to economic and technological challenges.As a consequence,the broader utilization of smart windows faces hindrances.To address this new generational multistimulus responsive chromic materials,our group has adopted a developmental strategy to create a poly(NIPAM)n-HV as a switchable material by anchoring active viologen(HV)onto a phase-changing poly(NIPAM)n-based smart material for better utility and activity.These constructed smart windows facilitate individualistic reversible switching,from a highly transparent state to an opaque state(thermochromic)and a red state(electrochromic),as well as facilitate a simultaneous dual-stimuli response reversible switching from a clear transparent state to a fully opaque(thermochromic)and orange(electrochromic)states.Absolute privacy can be attained in smart windows designed for exclusive settings by achieving zero transmittance.Each unique chromic mode operates independently and modulates visible and near-infrared(NIR)light in a distinct manner.Hence,these smart windows with thermal and electric dual-stimuli responsiveness demonstrate remarkable heat regulation capabilities,rendering them highly attractive for applications in building facades,energy harvesting,privacy protection,and color display.展开更多
Multifunctional lead-free double perovskites demonstrate remarkable potential towards applications in various fields.Herein,an environmentally-friendly,low-cost,high-throughput Cs_(2)NaFeCl_(6) single crystal with exc...Multifunctional lead-free double perovskites demonstrate remarkable potential towards applications in various fields.Herein,an environmentally-friendly,low-cost,high-throughput Cs_(2)NaFeCl_(6) single crystal with exceedingly high thermal stability is designed and grown.It obtains a cubic lattice system in the temperature range of 80-500 K,accompanied by a completely reversible chromatic variation ranging from yellow to black.Importantly,the intriguing thermochromism is proved to own extremely high reproducibility(over 1000 cycles)without a hysteretic effect,originating from its structural flexibility that including(i)the noteworthy distortion/deformation of[NaCl_(6)]5−and[FeCl_(6)]3−octahedra;(ii)order-disorder arrangement transition of[NaCl_(6)]5−and[FeCl6]3−octahedra as the function of temperature.This study paves the way towards a new class of smart windows and camouflage coatings with an unprecedented colour range based on a Cs_(2)NaFeCl_(6) perovskite.展开更多
An unexpected bistricyclic aromatic ene AF was synthesized in a tin(Ⅱ)chloride-mediated reductive aromatization reaction.The obtained AF showed a highly overcrowded structural conformation as revealed by X-ray crysta...An unexpected bistricyclic aromatic ene AF was synthesized in a tin(Ⅱ)chloride-mediated reductive aromatization reaction.The obtained AF showed a highly overcrowded structural conformation as revealed by X-ray crystallography.Interestingly,AF exhibited reversible high-contrast mechanochromism and thermochromism between pale and red color.The obvious chromism is likely ascribed to the conformation transformation and trace amount of diradical species formation upon stimulus.展开更多
A series of thermochromic polypropylene foils were prepared by embedding various leuco dye-developer-solvent systems in the polymer matrix. Bisphenol A, laurylgallate, ethylgallate and p-hydroxybenzoic acid methyl est...A series of thermochromic polypropylene foils were prepared by embedding various leuco dye-developer-solvent systems in the polymer matrix. Bisphenol A, laurylgallate, ethylgallate and p-hydroxybenzoic acid methyl ester were used as developers, crystal violet lactone and 3,3-bis-（1-n-butyl-2-methyl-3-indolyl）-phthalide as dyes and l-octanoic acid methyl ester as solvent. The molar ratio between the three components of the investigated leuco dye-developer-solvent systems was kept constant. All obtained polypropylene foils exhibit an excellent thermochromic behavior. The foils, prepared by extrusion technology, switch from color to colorless with increasing temperature. The influence of molecular structure of the developer on the intensity of the colored state and the influence of a developer-surfactant complex on the resulting thermochromic properties were investigated. The results are presented and discussed in detail according to a molecular model suggesting that the ring-opening process of the leuco dye is triggered by the formation of dye-developer complexes via H-bondings.展开更多
文摘Under the condition of solvothermal synthesis,the viologen ligand 1,1′-bis(3-carboxyphenyl)-(4,4′-bipyri-dine)dichloride(H_(2)bcbpy·2Cl)and KI are coordinated with the metal cadmium ions.A case of thermochromic coor-dination polymer[Cd(bcbpy)I_(2)]·2H_(2)O(1)was constructed.Complex 1 displays a 1D chain structure and exhibits thermochromic behavior.Under different temperature stimulation,the complex(ground)slowly changed from green to yellow-green,and with the increase of temperature,the color of complex 1 gradually deepened,and finally became orange-yellow.Therefore,complex 1 was prepared as a thermochromic film.In addition,we also performed electrochemical tests on complex 1,which showed that the complex is a semiconductor material.CCDC:2391802.
基金V.ACKNOWLEDGEMENTSThisworkwassupportedbytheNationalNatu-ralScienceFoundationofChina（No.21334001andNo.91127030）.V. ACKNOWLEDGEMENTS This work was supported by the National Natu- ral Science Foundation of China （No.21334001 and No.91127030）.
文摘We report a facile approach to water-dispersible polydiacetylene/rare earth ions nanocomposites with reversible thermochromism. The nanocomposites were prepared by doping rare earth ions Dy^3＋ or Sin^3＋ into layer-structured 10,12-pentacosadiynoic acid （PCDA） nanopar- ticles to obtain PCDA/rare earth ions nanocomposites （PCDA-RE） and subsequently annealing PCDA-RE at the temperature slightly higher than the melting point of pure PCDA crystals, followed by topochemically polymerizing the annealed PCDA-RE. The polymerized PCDA-RE, i.e. poly（10,12-pentacosadiynoic acid）/rare earth ions nanocomposites （PDARE： PDA-Dy or PDA-Sm）, are largely reversible （PDA-Sm） or even completely reversible （PDA-Dy） in the thermochromism, while, without the doping, pure PDA is completely irreversible. It is confirmed that, PDA-RE are also layer-structured with a d-spacing of 5.4 nm, higher than the d-spacing of pure PDA （4.7 nm）. In PDA-RE, the rare earth ions form a layer in-between and interact strongly with the PDA bilayers, being responsible for the high degree or even the complete reversibility. This is the first example to make PDA completely reversible through the doping of rare earth ions; the annealing process is essential for the complete reversibility since it removes any defects in the structure.
基金support from the National Natural Science Foundation of China(51922020,52090034)the Fundamental Research Funds for the Central Universities(BHYC1707B)。
文摘The highly integrated and miniaturized next-generation electronic products call for high-performance electromagnetic interference(EMI)shielding materials to assure the normal operation of their closely assembled components.However,the most current techniques are not adequate for the fabrication of shielding materials with programmable structure and controllable shielding efficiency.Herein,we demonstrate the direct ink writing of robust and highly conductive Ti3C2Tx MXene frames with customizable structures by using MXene/AlOOH inks for tunable EMI shielding and electromagnetic wave-induced thermochromism applications.The as-printed frames are reinforced by immersing in AlCl_(3)/HCl solution to remove the electrically insulating AlOOH nanoparticles,as well as cross-link the MXene sheets and fuse the filament interfaces with aluminum ions.After freeze-drying,the resultant robust and porous MXene frames exhibit tunable EMI shielding efficiencies in the range of 25-80 dB with the highest electrical conductivity of 5323 S m−1.Furthermore,an electromagnetic wave-induced thermochromic MXene pattern is assembled by coating and curing with thermochromic polydimethylsiloxane on a printed MXene pattern,and its color can be changed from blue to red under the high-intensity electromagnetic irradiation.This work demonstrates a direct ink printing of customizable EMI frames and patterns for tuning EMI shielding efficiency and visualizing electromagnetic waves.
基金financially supported by the Teaching Quality Project of West Anhui Health Vocational College(YJZLGC201713)
文摘Using 1,1-bis(isoquinoline)-1,4-phenyldimethylenyl(BIQPM^(2+))cation as template,a new tetrameric(Bi_(4)I_(16))^(4-)-iodobismuthate-containing hybrid with formula of(BIQPM)_(2)(Bi_(4)I_(16)·H_(2)O(1),has been prepared under solvothermal conditions.The centrosymmetric (Bi_(4)I_(16))^(4- ) tetraanion is constructed from four edge-shared slightly distorted BiI6 octahedrons.Due to the presence of larger conjugated system(isoquinoline ring),strongπ···πstacking interactions can be observed.Besides,strong I···I interactions can be monitored and extends the 0-D (Bi_(4)I_(16))^(4- )cluster to a quasi-1-D chain.The smaller energy gap of 2.13 eV is led by these non-covalent interactions.Its infrared emission might be caused by strong charge transfer between anions and cations.Furthermore,the reversible thermochromic behavior with low chromotropic temperature of 80℃can be observed,whose mechanism was discussed.
基金supported by the National Natural Science Foundation of China(No.21573092,No.21573087 and No.21873039)。
文摘Three kinds of thermochromic materials(DC8,DC12,DC16)were synthesized by linking the rigid 1,4-bis[2-(4-pyridyl)ethenyl]-benzene(bpeb)with different lengths of alkyl chains.They exhibit remarkable fluorescent color changes under the irradiation of 365 nm light with elevating temperature,which is supposed to be caused by the transition between the crystal state and the amorphous state.Interestingly,the DC16 solid also has a photochromic character.It should be noticed that the phase transition temperatures of three materials measured by differential scanning calorimetry are higher than those of the fluorescence color changes during the heating process.Thus,the allochroic effect is attributed to the synergistic effect of both heating and photo-inducement(365 nm).Ethanol can turn the heated powder into the initial crystal again which indicates that their thermochromic behavior is reversible and makes the fluorescence recover.
基金partial support from the Living Circular Labels project,funded by the Taskforce for Applied Research SIA’s KIEM programme(No.CIE.06.007)in the Netherlands。
文摘By leveraging the unique qualities of microorganisms,engineered living materials(ELMs)offer functional and economic advantages in everyday applications along with notable ecological benefits.This study contributes to the growing field of biodesign by examining the potential of Flavobacteria for thermochromic ELMs.Many Flavobacteria,commonly found in marine environments,produce iridescent structural colorations as their colonies expand on semi-solid surfaces through gliding motility.In this study,we analyzed the effects of temperature variations on flavobacterium Cellulophaga lytica PLY A 2,characterizing distinct changes in colony growth and iridescent colorations at a macroscopic and microscopic scale.Using scanning electron microscopy,we investigated the relationship between iridescent color and the underlying cell-based optical structures.By providing insights into the temperature-responsive behavior of Flavobacteria,our findings highlight their potential for future thermochromic ELMs-with applications ranging from sustainable food packaging to smart textiles-while encouraging further characterization studies within biodesign research.
基金JSPSKAKENHI Grant-in-Aid for Scientific Research(C),Grant/Award Number:JP20K05475(Tomohiko Nishiuchi)Scientific Research(B),Grant/Award Number:JP21H01887(Kenji Kamada)。
文摘Since the discovery of the triphenylmethyl(trityl)cation 120 years ago,a variety of aromatic cations having various colors and luminescence properties have been rigorously studied.Many,differently substituted trityl cations have been synthesized,and their optical properties have been elucidated.However,the optical properties of the parent,non-substituted and highly reactive trityl cation,which was observed to be very weakly luminescent,have not been subjected to detailed investigation.In the effort described herein,we explored the optical nature of non-substituted trityl hexafluorophosphate(PF_(6))in the crystalline state.Trityl PF_(6) was found to exist as two crystal polymorphs including a yellow(Y)and an orange(O)form.Moreover,we observed that these crystalline forms display crystalline-state emission with different colors.The results of X-ray crystallographic analysis showed that the two polymorphs have totally different molecular packing arrangements.Furthermore,an investigation of their optical properties revealed that the O-crystal undergoes a distinct color change to yellow upon cooling as a consequence of a change in the nature of the charge transfer interaction between the cation and PF6 anion,and that both the Y-and O-crystal exhibit phosphorescence.
基金the National Natural Science Foundation of China(22171105 and 22471096)Natural Sci-ence Foundation of Shandong Province(ZR2022YQ14,ZR2022QB127 and ZR2022QB221)Special Foundation of Taishan Scholar Project and Young Innovative Team Project for Colleges and Universities of Shandong Province(2024KJH053).
文摘Stimuli-responsive luminescent switching materials with multifunctional properties are highly essential for advanced photonic applications,yet achieving such capabilities in halide perovskites continues to pose a signif-icant challenge.In this work,we explore a new water-stimuli-responsive zero-dimensional(0D)Sb-based halide of[PhPz]_(2)SbCl_(7)·2H_(2)O(PhPz=phenylpiperazine),which consists of isolated[SbCl_(6)]^(3-) octahedra in[PhPz]2+cationic matrix with vip H_(2)O molecules.Under UV excitation,[PhPz]_(2)SbCl_(7)·2H_(2)O emits intense broadband red light with maximum emission at 645 nm,and combined optical characterization and theoretical calculations confirm that this luminescence originates from self-trapped excitons(STEs).Interestingly,the free water molecules can reversibly leave and entry the crystal lattice during heating-cooling cycles accompanied by the formation of dehydrated phase,which displays strong yellow emission with maximum peak at 580 nm.Therefore,reversible luminescent switching between red and yellow emission is achieved through controllable removal and adsorption process of vip H_(2)O.By virtue of this reversible thermochromic switching,this halide can be used to detect the trace amount of water in various organic solvents and humidity of moist air.In addition,such switchable dual emission further realizes application in anti-counterfeiting and information encryption-decryption.This work deepens the understanding of structure-property relationships and expands the application range of oD metal halides.
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 Key Research and Development Program of China(No.2022YFB3603802)the Key Research and Development Program of Jilin Scientific and Technological Development Program(No.20220201068GX)+1 种基金the National Natural Science Foundation of China(Nos.51902127,62374073)Changbai Mountain Industrial Project R&D Leading Team,Jilin Provincial Department of Science and Technology,China.
文摘Thermochromic materials based on solid-state oxides exhibit many potential photo-thermal regulation applications.Herein,we report a new thermochromic pure-phase CaCrO_(4) pigment with merits of high chromatic aberration,fully reversible thermochromism,and high stability.CaCrO_(4) crystalized into a tetragonal zircon-type structure,which showed a successively reversible color change from greenish yellow to reddish orange with the highest chromatic aberration (ΔE^(*)_(CIE)) of 59.60.In situ variable temperature X-ray diffraction analysis results revealed that the expansion of the lattice was uniaxial along the c-axis with a dilation rate of 2.06×10^(−5),while that along the a-axis remained nearly unchanged in the temperature range of 25–575℃.In situ variable temperature UV–vis absorption spectra of CaCrO_(4) revealed a successive bandgap reduction with an average temperature dependency rate(dE_(g)/dT)_(aver age) of 0.27 meV K^(−1).Continuous color change or bandgap reduction originated from the successive elongation of Cr–O bonds in the CrO_(4) tetrahedral chromophore in the lattice.The most sensitive temperature range was between 175℃ and 400℃,which rendered a naked-eye-detection accuracy rate of over 85%for a standard temperature deviation(ΔT)of 25℃,demonstrating the potential of the pigment as a pan-bottom temperature indicator for healthy cooking.
基金the funding and generous support of the National Natural Science Foundation of China(52103263,52271249)the Key Project of International Science&Technology Cooperation of Shaanxi Province(2023-GHZD-09)+5 种基金the Key Project of Science Foundation of Education Department of Shaanxi Province(22JY011)the Key Project of Scientific Research and Development of Shaanxi Province(2023GXLH-070)the Qinchuangyuan"Scientist+Engineer"Team of Shaanxi Province(2023KXJ-069)the Key Research and Development Program of Shaanxi(2023-YBGY-488)the Sci-tech Innovation Team of Shaanxi Province(2024RS-CXTD-46)the Key Research and Development Program of Shaanxi Province(2020ZDLGY13-11).
文摘All-season thermal management with zero energy consumption and emissions is more crucial to global decarbonization over traditional energy-intensive cooling/heating systems.However,the static single thermal management for cooling or heating fails to self-regulate the temperature in dynamic seasonal temperature condition.Herein,inspired by the dual-temperature regulation function of the fur color changes on the backs and abdomens of penguins,a smart thermal management composite hydrogel(PNA@H-PM Gel)system was subtly created though an"on-demand"dual-layer structure design strategy.The PNA@H-PM Gel system features synchronous solar and thermal radiation modulation as well as tunable phase transition temperatures to meet the variable seasonal thermal requirements and energy-saving demands via self-adaptive radiative cooling and solar heating regulation.Furthermore,this system demonstrates superb modulations of both the solar reflectance(ΔR=0.74)and thermal emissivity(ΔE=0.52)in response to ambient temperature changes,highlighting efficient temperature regulation with average radiative cooling and solar heating effects of 9.6℃in summer and 6.1℃in winter,respectively.Moreover,compared to standard building baselines,the PNA@H-PM Gel presents a more substantial energy-saving cooling/heating potentials for energy-efficient buildings across various regions and climates.This novel solution,inspired by penguins in the real world,will offer a fresh approach for producing intelligent,energy-saving thermal management materials,and serve for temperature regulation under dynamic climate conditions and even throughout all seasons.
基金supported by the Fundamental Research Funds for the Central Universities(xxj022019009)。
文摘Photothermoelectric(PTE)photodetectors with selfpowered and uncooled advantages have attracted much interest due to the wide application prospects in the military and civilian fields.However,traditional PTE photodetectors lack of mechanical flexibility and cannot operate independently without the test instrument.Herein,we present a flexible PTE photodetector capable of dual-mode output,combining electrical and optical signal generation for enhanced functionality.Using solution processing,high-quality MXene thin films are assembled on asymmetric electrodes as the photosensitive layer.The geometrically asymmetric electrode design significantly enhances the responsivity,achieving 0.33 m A W^(-1)under infrared illumination,twice that of the symmetrical configuration.This improvement stems from optimized photothermal conversion and an expanded temperature gradient.The PTE device maintains stable performance after 300 bending cycles,demonstrating excellent flexibility.A new energy conversion pathway has been established by coupling the photothermal conversion of MXene with thermochromic composite materials,leading to a real-time visualization of invisible infrared radiation.Leveraging this functionality,we demonstrate the first human-machine collaborative infrared imaging system,wherein the dual-mode photodetector arrays synchronously generate human-readable pattern and machine-readable pattern.Our study not only provides a new solution for functional integration of flexible photodetectors,but also sets a new benchmark for human-machine collaborative optoelectronics.
文摘Correction for‘A new methylviologen-templated zinc gallophosphate zeolite with photo-/thermochromism,fluorescent and photoelectric properties’by Chunyao Tao,et al.,Inorg.Chem.Front.,2016,DOI:10.1039/c5qi00283d.
基金the National Natural Science Foundation of China(no.:21271081)for financial support.
文摘A new zinc gallophosphate zeolite[Zn_(5.8)Ga_(14.2)(PO_(4))_(2)0F_(3.2)(H_(3)O)_(3)]|C_(12)H_(14)N_(2)|_(3)·3H_(2)O(noted as JU104)with a USI zeotype structure has been solvothermally synthesized by using in situ generated methylviologen(MV)as the template.JU104 has two-dimensional interconnected 12-ring and 10-ring channels running along the[100]and[010]direction,respectively.It exhibits dual thermochromism and photochromism with a broad photo-response range(UV light to visible light)and a long-lived charge-separated state,as well as variable fluorescent and photoelectric properties.Moreover,the multi photo/thermo-induced colors occurring in JU104 make it unusual as compared to other inorganic photo/thermochromism compounds.The MV-templated JU104 zeolite may function as a new efficient electron-transfer system for potential applications in photo/thermochromism and solar energy conversion.
文摘A transient measurement technique by using narrow-band thermochromic liquid crystal （TLC） is employed to determine temperature and heat transfer coefficient （HTC） distribution on inner surfaces of the typical lamilloy configurations. With this technique, both local HTC distribution and average HTC distribution could be obtained. The experimental results indicate that the variation of the porosity ratio, the one that the area of impingement holes divided by that of the plate, has a great effect on the HTC distribution on the inner surfaces. Heat exchange of inner surfaces varies directly as the porosity ratio. The impingement Reynolds number ranges from 20 000 to 50 000. The average HTC of inner surfaces bears a linear relationship with the Reynolds number.
文摘Thermochromic polymers will play an extremely important role in the next future. The physical background of thermochromism and the state of development of thermochromic polymers based on light absorption effects are reported. In detail, the interactions between the polymer matrix and the thermochromic composite - composed of leuco or indicator dyes - are discussed on a molecular level. Thermochromic hydrogels with extremely high transparency, an outstanding switching behavior from colorless to colored or between different colors is presented. Preparation of thermosetting and thermoplastic polymers, including the resulting optical, and, for the first time, the mechanical properties are discussed in relation to matrix tuned high-resistant microcapsules.
基金supported by the National Research Foundation (NRF)grants funded by the Ministry of Education (2020R1A6A1A03038817),Republic of Korea。
文摘Functional materials may change color by heat and electricity separately or simultaneously in smart windows.These materials have not only demonstrated remarkable potential in the modulation of solar radiation but are also leading to the development of indoor environments that are more comfortable and conducive to improving individuals'quality of life.Unfortunately,dual-responsive materials have not received ample research attention due to economic and technological challenges.As a consequence,the broader utilization of smart windows faces hindrances.To address this new generational multistimulus responsive chromic materials,our group has adopted a developmental strategy to create a poly(NIPAM)n-HV as a switchable material by anchoring active viologen(HV)onto a phase-changing poly(NIPAM)n-based smart material for better utility and activity.These constructed smart windows facilitate individualistic reversible switching,from a highly transparent state to an opaque state(thermochromic)and a red state(electrochromic),as well as facilitate a simultaneous dual-stimuli response reversible switching from a clear transparent state to a fully opaque(thermochromic)and orange(electrochromic)states.Absolute privacy can be attained in smart windows designed for exclusive settings by achieving zero transmittance.Each unique chromic mode operates independently and modulates visible and near-infrared(NIR)light in a distinct manner.Hence,these smart windows with thermal and electric dual-stimuli responsiveness demonstrate remarkable heat regulation capabilities,rendering them highly attractive for applications in building facades,energy harvesting,privacy protection,and color display.
基金The research was funded by the National Natural Science Foundation of China(No.51802120,51872126,22075103,51672111)Guangdong Basic and Applied Basic Research Foundation for Distinguished Young Scholar(No.2019B151502030)+7 种基金Natural Science Foundation of Guangdong Province(No.2018030310181)the Science and Technology Plan Project of Guangzhou(No.202002030159)Guangdong Basic and Applied Basic Research Foundation for Young Scholar(No.2020A1515111057)‘100 Talents Program of Hebei Province’(No.E2014100008)the Fundamental Research Funds for the Central Universities(No.21619406)X.Y.thanks for the Special Funds for the Cultivation of Guangdong College Students'Scientific and Technological Innovation("Climbing Program"Special Funds)(No.pdjh2019a0055)J.Fan also thanks for the project support for"Young Top talents"in the Pearl River Talent Project of Guangdong Province(2017GC010424)the Guangdong Provincial Innovation and Entrepreneurship Project(grant 2016ZT06D081).
文摘Multifunctional lead-free double perovskites demonstrate remarkable potential towards applications in various fields.Herein,an environmentally-friendly,low-cost,high-throughput Cs_(2)NaFeCl_(6) single crystal with exceedingly high thermal stability is designed and grown.It obtains a cubic lattice system in the temperature range of 80-500 K,accompanied by a completely reversible chromatic variation ranging from yellow to black.Importantly,the intriguing thermochromism is proved to own extremely high reproducibility(over 1000 cycles)without a hysteretic effect,originating from its structural flexibility that including(i)the noteworthy distortion/deformation of[NaCl_(6)]5−and[FeCl_(6)]3−octahedra;(ii)order-disorder arrangement transition of[NaCl_(6)]5−and[FeCl6]3−octahedra as the function of temperature.This study paves the way towards a new class of smart windows and camouflage coatings with an unprecedented colour range based on a Cs_(2)NaFeCl_(6) perovskite.
基金Innovation Program of Shanghai Municipal Education Commission(No.2019-01-07-00-05-E00012)Program for Changjiang Scholars and Innovative Research Team in University for financial support+1 种基金the financial supports sponsored by Shanghai Sailing Program(No.19YF1412900)the Fundamental Research Funds for the Central Universities。
文摘An unexpected bistricyclic aromatic ene AF was synthesized in a tin(Ⅱ)chloride-mediated reductive aromatization reaction.The obtained AF showed a highly overcrowded structural conformation as revealed by X-ray crystallography.Interestingly,AF exhibited reversible high-contrast mechanochromism and thermochromism between pale and red color.The obvious chromism is likely ascribed to the conformation transformation and trace amount of diradical species formation upon stimulus.
基金This work was financially supported by the Bundesministerium fur Bildung und Arbeit (No. 0329820E).
文摘A series of thermochromic polypropylene foils were prepared by embedding various leuco dye-developer-solvent systems in the polymer matrix. Bisphenol A, laurylgallate, ethylgallate and p-hydroxybenzoic acid methyl ester were used as developers, crystal violet lactone and 3,3-bis-（1-n-butyl-2-methyl-3-indolyl）-phthalide as dyes and l-octanoic acid methyl ester as solvent. The molar ratio between the three components of the investigated leuco dye-developer-solvent systems was kept constant. All obtained polypropylene foils exhibit an excellent thermochromic behavior. The foils, prepared by extrusion technology, switch from color to colorless with increasing temperature. The influence of molecular structure of the developer on the intensity of the colored state and the influence of a developer-surfactant complex on the resulting thermochromic properties were investigated. The results are presented and discussed in detail according to a molecular model suggesting that the ring-opening process of the leuco dye is triggered by the formation of dye-developer complexes via H-bondings.
