Two photochromic compounds with the pyrazolonering as the photochromic functional structure, 2(1phenyl3methyl4benzoformylpyrazolone5)thiosemicarbazone(PMBPTSC) and 2(1phenyl3methyl4benzoformylpyrazolone5...Two photochromic compounds with the pyrazolonering as the photochromic functional structure, 2(1phenyl3methyl4benzoformylpyrazolone5)thiosemicarbazone(PMBPTSC) and 2(1phenyl3methyl4benzoformylpyrazolone5)smethylthiosemicarbazone(PMBPMTSC), were synthesized and characterized by elemental analysis, MS, IR spectra, NMR spectra. The crystal structure of the photocolored product of PMBPTSC was determined by single crystal XRD analysis. The results show that the photochromic phenomenon is due to the photoisomerization from enol form to keto form. Their photochromic properties were studied by powderUV reflectance spectra under the irradiation of 200—380 nm light. The firstorder rate constants of the photocoloring reaction were found to be 780×10 -3 s -1 for compound 1A and 103×10 -3 s -1 for compound 2A.展开更多
Incorporation of photochromic compounds to the polymer through chemical bonding will result in an enhancement of photoactivity and stabilization of optical properties.Here,spiropyran(SP)was introduced into polyurethan...Incorporation of photochromic compounds to the polymer through chemical bonding will result in an enhancement of photoactivity and stabilization of optical properties.Here,spiropyran(SP)was introduced into polyurethane(PU)through semi-continuous emulsion copolymerization to get waterborne polyurethane dispersion(SPU).Studies on photochromic properties by UV-vis technique demonstrated the absorption intensity increased with the increasing of SP concentration and the colorless film turned to purple under UV irradiation.The kinetics for ring-opening and ring-closing reaction against SP were both first order,but the rate constants decreased with the increasing of SP concentration.The prepared SPU films showed reasonable photostability and photoreversibility according to the convenient test methods under UV-vis irradiation.Temperature dependence studies demonstrated that the photobleaching rate increased at higher temperatures with the same SP concentration.The chemical combination between SP and isocyanate(NCO)end group of polyurethane was confirmed through swelling experiments.Morphology studies were conducted by scanning electron microscope(SEM)micrographs and showed good compatibility between SP and PU.展开更多
Photochromic and photoluminescence materials show bright colors under different excitation conditions,and thus,these functional materials have been applied in many fields.Based on the photochromic and photoluminescenc...Photochromic and photoluminescence materials show bright colors under different excitation conditions,and thus,these functional materials have been applied in many fields.Based on the photochromic and photoluminescence theories,a block copolymer,which could be directly processed into nanofibers by electrospinning,was successfully prepared through atom transfer radical polymerization(ATRP).To synthesize the block copolymer,a vinyl monomer containing a spiropyran unit was employed to prepare the photochromic chain segment,and a polymethyl methacrylate(PMMA)chain segment was introduced to improve the processability of the block copolymer.Acting as the photoluminescence unit,the rare earth complex was linked to the side chain through coordination bonding between the rare earth ions and the ester groups of PMMA.When the photochromic and photoluminescence block copolymer was exposed to different wavelengths of ultraviolet(UV)light and visible(Vis)light,it could show white,red,green,yellow,and blue-purple.These results provide the potential of the as-prepared photochromic and photoluminescence block copolymer for application in fibers and fabrics.展开更多
Transparent wood(TW)is a wood-based biomaterial with several advantages,such as high optical transmittance,low thermal conductivity,and tunable haze.TW is functionalized according to its transparency to broaden its ap...Transparent wood(TW)is a wood-based biomaterial with several advantages,such as high optical transmittance,low thermal conductivity,and tunable haze.TW is functionalized according to its transparency to broaden its applications in different fields.Several studies have examined wood functionalization in recent years;however,few studies have reported photochromic TW(PTW)for ultraviolet(UV)-shielding window applications.Herein,PTW was obtained by infiltrating the delignified wood template with photochromic silver bromide(AgBr)nanoparticles and a pre-polymerized methyl methacrylate(MMA)mixture solution.The obtained PTW can adjust the luminous flux on change in the color in the visible light region.The photochromic properties were examined,and the optical properties of the composites were characterized using UV-Vis spectrophotometry.Light transmittance of PTW was up to 86.5%at 800 nm before UV irradiation,and it decreased to 70.1%at 800 nm after UV irradiation,as the wood color changed from colorless to dark purple under UV irradiation.Thus,this work not only achieves high-value utilization of wood,but also produces a new material that can be used in varied fields,such as UV-shielding,energy saving,and smart building.展开更多
Copper-cadmium halide doped photochromic glass coating on plate glass has been prepared by a sol-gel process. The sample shows reversible photochromic effect. The results of X-ray diffraction (XRD) and infrared (IR...Copper-cadmium halide doped photochromic glass coating on plate glass has been prepared by a sol-gel process. The sample shows reversible photochromic effect. The results of X-ray diffraction (XRD) and infrared (IR) spectrum investigations indicate that the photochromic phase of tile coating is CuBrxCl1-x, solid solution, and that the structure network of the coating is connected with the bonds of Si-O-Si, Si-O-B and Si-O-Al.展开更多
We have studied the dynamic and static processes occurring in disordered multiparticle colloidal Ag aggregates with natural structure and affecting their plasmonic absorption spectra under pico-and nanosecond pulsed l...We have studied the dynamic and static processes occurring in disordered multiparticle colloidal Ag aggregates with natural structure and affecting their plasmonic absorption spectra under pico-and nanosecond pulsed laser radiations, as well as the physical origin responsible for these processes. We have shown that depending on the duration of the laser pulse,the mechanisms of laser modification of such aggregates can be associated both with changes in the resonant properties of the particles due to their heating and melting(picosecond irradiation mode) and with the particle shifts in the resonant domains of the aggregates(nanosecond pulses) which depend on the wavelength, intensity, and polarization of the radiation.These mechanisms result in formation of a narrow dip in the plasmonic absorption spectrum of the aggregates near the laser radiation wavelength and affect the shape and position of the dip. The effect of polydispersity of nanoparticle aggregates on laser photochromic reaction has been studied.展开更多
In this paper, the influence of heat treatmenton transmittance and the photochromic of ion exchange pho-tochromic glass was studied, the microstructure of glass aswell as the forming of AgX crystals were discussed. It...In this paper, the influence of heat treatmenton transmittance and the photochromic of ion exchange pho-tochromic glass was studied, the microstructure of glass aswell as the forming of AgX crystals were discussed. It is be-lieved that heat treatment temperature affects precipitating ofAgX crystal .and the AgX crystal is a dominant factor af-fecting surface photochromic properties of ion exchange pho-tochromic glass.展开更多
The photochromic properties of photochromicglasses containing both copper halides and cadmiumhalides depend mainly upon the body glass composi-tion. The composition range of glass matrix can bedescribed by F=[(R<s...The photochromic properties of photochromicglasses containing both copper halides and cadmiumhalides depend mainly upon the body glass composi-tion. The composition range of glass matrix can bedescribed by F=[(R<sub>2</sub>0+MO)-Al<sub>2</sub>0<sub>3</sub>]/B<sub>2</sub>0<sub>3</sub>·In this paper,the basic structure of the glasses is investigatedin terms of IR and Raman spectroscopy in detail.The results demonstrate that the network of bodyglass is constructed by [SiO<sub>4</sub>], [BO<sub>3</sub>], [BO<sub>4</sub>] and[Al0<sub>4</sub>], in which [BO<sub>3</sub>] and [BO<sub>4</sub>] are interconnec-ted into two kinds of borate groups and a kind ofboroxol ring. Finally, the relationships betweenstructure and properties have been discussed on thescale of molecules and molecular groups.展开更多
We successfully synthesized dithienylethene with amino groups. Then, we successfully prepared Langmuir-Blodgett (LB) films of the dithienylethene having ammonium cation group when dodecyl benzene sulfonic acid was emp...We successfully synthesized dithienylethene with amino groups. Then, we successfully prepared Langmuir-Blodgett (LB) films of the dithienylethene having ammonium cation group when dodecyl benzene sulfonic acid was employed as an anionic counter ion. From X-ray diffraction profiles, however, it was demonstrated that they did not form well-defined layered structure;X-ray diffraction peaks were much broadened. Photochromic behavior was confirmed in the LB films. Unfortunately, the LB films were not so stable;photochromic reaction was observed only several times in the LB films.展开更多
Fulgide 1-E doped in polystyrene polymer films was heated at various annealing temperatures.Upon irradiation with UV light(366 nm),fulgide 1-E undergoes a conrotatory ring closure to the pink colored closed form 1-C.T...Fulgide 1-E doped in polystyrene polymer films was heated at various annealing temperatures.Upon irradiation with UV light(366 nm),fulgide 1-E undergoes a conrotatory ring closure to the pink colored closed form 1-C.The later color was switched back to the original color when the films were irradiated with white light.The kinetics of photocoloration and photobleaching processes were followed spectrophotometrically by monitoring the absorbance of the ring closed product 1-C at itsλ_(max) of 525 nm.The fir...展开更多
Photochromic wood was fabricated by coating microencapsulated photochromic material(MP)/polydimethylsiloxane composites onto wood using a simple drop-coating method.Urea-melamine–formaldehyde resin was used to microe...Photochromic wood was fabricated by coating microencapsulated photochromic material(MP)/polydimethylsiloxane composites onto wood using a simple drop-coating method.Urea-melamine–formaldehyde resin was used to microencapsulate the photochromic material(PM)via in situ polymerization.The concentration of the MP affected the photochromic property of the wood surface.The total color change(ΔE*)reached 82.2 when the concentration of the composite coating is 8%.Adhesion tests confirmed that the composite coating adhered firmly to the wood.This method is potentially useful for the production of functional wooden products,such as anti-counterfeiting materials and aesthetic wood.展开更多
1, 2 - bis(3-Methylbenzo[b]thiophen-2-yl)cycloalkene derivatives 3a, 3b and 1- (2-methylbenzo[b]thiophen - 3 - yl ) - 2 - (3 - methylbenzo[b]thiophen - 2 - yl)cyclohexene 9 were synthesized. The obtained compounds exh...1, 2 - bis(3-Methylbenzo[b]thiophen-2-yl)cycloalkene derivatives 3a, 3b and 1- (2-methylbenzo[b]thiophen - 3 - yl ) - 2 - (3 - methylbenzo[b]thiophen - 2 - yl)cyclohexene 9 were synthesized. The obtained compounds exhibited photochromic property and the absorption bands of the colored forms 4a. 4b and 10 centered between 360-440 nm thus possessing the sensitivity at the wavelength of the newly developed InGaN diode laser.展开更多
Photochromism is a phenomenon that a compound undergoes a reversible color change with the change of the wavelength of the irradiating light. Many photochromic compounds have been used in textiles as photochromic pigm...Photochromism is a phenomenon that a compound undergoes a reversible color change with the change of the wavelength of the irradiating light. Many photochromic compounds have been used in textiles as photochromic pigments.In this paper, some special techniques are used to prepare a photochromic compound of spirooxazines with an improved yield. Another photochromic spirooxazine with a sulfonate group which is soluble in water is also successfully synthesized. Tests are also conducted to find that they both display good photochromism in proper states.展开更多
Photochromic materials with multicolor upconversion reversible modulations are attractive in optical switching devices.Herein,the fabricated YNbO_(4):Er^(3+)/Tm^(3+)/Yb^(3+) materials exhibit excellent photochromism a...Photochromic materials with multicolor upconversion reversible modulations are attractive in optical switching devices.Herein,the fabricated YNbO_(4):Er^(3+)/Tm^(3+)/Yb^(3+) materials exhibit excellent photochromism and multicolor upconversion properties from green,red to near infrared(NIR) emissions with increasing Yb concentrations.Reversible multiband upconversion modulations are achieved by alternating light(365 and 405 nm) or thermal stimuli.After 365 nm irradiation,the luminescence color changes from yellow to red,the luminescent photoswitching contrast reaches up to 86.21%(green),82.12%(red) and 77.38%(NIR) in the Y_(0.83)Er_(0.01)Tm_(0.01)NbO_(4):0.15 Yb sample.Besides,the upconversion emission intensity before and after photochromic reaction shows remarkable change in a wide temperature range of 298-718 K.These results indicate that the Er^(3+)/Tm^(3+)/Yb^(3+) tri-doped YNbO_(4) materials can be a good candidate in optical switching and data storage applications.展开更多
We herein present a simple,fast,low-temperature,post-glass melting fabrication protocol in which a photochromic silver cation based modified zone is incorporated within silver metaphosphate glass(AgPO_(3)).The selecti...We herein present a simple,fast,low-temperature,post-glass melting fabrication protocol in which a photochromic silver cation based modified zone is incorporated within silver metaphosphate glass(AgPO_(3)).The selection of AgPO_(3)glass is mainly based on its relative“soft”nature(T_(g)=192℃)that enables the integration of silver cations from the surface deposited AgCl layer,while being transparent in most of the visible range,and therefore suitable for smart photochromic window applications.The suggested synthesis procedure permits the controlled formation of a silver cation modified layer within the host glass matrix,while the characteristics of the layer itself can be adjusted correspondingly.Our findings reveal a direct relationship between the developed composite AgCleAgPO_(3)glass photochromic response and the morphological features of the integrated layer,i.e.,thickness and position.More importantly,the photochromic response time with various UV irradiation doses is also studied,where remarkable response times of several seconds are obtained.Processes and efforts to further enhance the photochromic performance by utilizing the presence of silver nanoparticles within the glass matrix are also presented and discussed.展开更多
Stimulus-responsive materials are fundamental to the broad and ever-growing field of intelligence research,which bridge intelligent systems with the Internet of Things(loT)in future lifestyles.Among these materials,wr...Stimulus-responsive materials are fundamental to the broad and ever-growing field of intelligence research,which bridge intelligent systems with the Internet of Things(loT)in future lifestyles.Among these materials,writable materials have received great interest;however,carbonization and irreversible writing processes are generally inevitable for extensively investigated organic compounds.Photochromism is a potential mode of composing information.Nevertheless,inorganic materials usually exhibit weak photochromic effects.Here,a novel strategy of designing high-entropy perovskite(HEP)oxides is put forward to develop a new inorganic photochromic system with satisfying performance.A series of HEP oxides are synthesized for the first time.Benefiting from excellent photochromic features,real-time information encoding was achieved.The mechanism-related photochromism is also discussed.Distinct from the previous works,it is believed that the present photochromic-based HEP oxides provide a new and manyfold research space for the future development of conventional writable materials and the disclosing of unprecedented properties and phenomena.展开更多
Three novel dithienylethenes modified by bifluoroboron β-diketonate fragments have been successfully developed. Upon blue light irradiation, they reached photostationary state within 2-5 s, as well as 100% conversion...Three novel dithienylethenes modified by bifluoroboron β-diketonate fragments have been successfully developed. Upon blue light irradiation, they reached photostationary state within 2-5 s, as well as 100% conversion ratio and photocyclization quantum yield of > 0.70. Such fascinating photochromism were endowed by collaborative role of electron-withdrawing effect of BF_(2)bdk group to reduce HOMO-LUMO electronic gap for the open isomer, together with intramolecular hydrogen bonds and CH-π interactions favoring antiparallel conformation fixation. Moreover, they displayed specific discrimination and photoswitchable bacterial imaging for S. aureus.展开更多
Here,we report the ability of spiropyrans to initiate two-photon polymerization(TPP)for the first time in the literature.The comparison and synergies between the spiropyran photochromic molecule of interest,namely 6-n...Here,we report the ability of spiropyrans to initiate two-photon polymerization(TPP)for the first time in the literature.The comparison and synergies between the spiropyran photochromic molecule of interest,namely 6-nitro-BIPS,and well-known photoinitiators of radical photopolymerization have been studied.The spiropyran(SPy)molecule can initiate TPP in the presence of trifunctional acrylic monomers and create true 3D structures.The comparison with Irgacure 819,a well-known Type-I photoinitiator,shows that SPy has a comparable capability for TPP.In addition,the combination of SPy with methyl diethanolamine increased the reactivity of both one-and two-photon polymerizations.In the last section,we discuss which SPy isomer is the active photochromic species capable of generating radicals for initiating two-photon polymerization.展开更多
We introduce a high-density three-dimensional optical data storage approach by using a pyrryl-sub-stituted fulgide photochromic material with a method of single-beam two-photon recording and fluorescence confocal read...We introduce a high-density three-dimensional optical data storage approach by using a pyrryl-sub-stituted fulgide photochromic material with a method of single-beam two-photon recording and fluorescence confocal readout. The detailed information about the photochromic material and the experimental setup are presented. The experiments about multi-layered recording and readout are carried out with a 100-μm-thick transparent photochromic material film. The results show that the lateral resolution is better than 1 μm, and the longitudinal resolution is about 3 μm. Besides, the readout times for the recorded data aredesirable when using a readout laser power smaller than 5 mW.展开更多
TiO2 nanotube arrays were prepared by means of an electrochemical anodization technique in an organic electrolyte solution doped with polyvinyl pyrrolidone (PVP) and were subsequently modified with phosphomolybdic aci...TiO2 nanotube arrays were prepared by means of an electrochemical anodization technique in an organic electrolyte solution doped with polyvinyl pyrrolidone (PVP) and were subsequently modified with phosphomolybdic acid (PMoA) to obtain PMoA/TiO2 nanotube arrays. The microstructure and photochromic properties were investigated via X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), ultraviolet-visible spectroscopy (UV-vis), and X-ray photoelectron spectroscopy (XPS). The results indicated that the Keggin structure of PMoA and the nanotube structure of TiO2 were not destroyed, and there was a strong degree of interaction between PMoA and TiO2 at the biphasic interface with lattice interlacing during the compositing process. The XPS results further indicated that there was a change in the chemical microenvironment during the formation process of the composite, and a new charge transfer bridge was formed through the Mo-O-Ti bond. Under visible light irradiation, the colorless PMoA/TiO2 nanotube array quickly turned blue and exhibited a photochromic response together with reversible photochromism in the presence of H2O2. After visible light irradiation for 60s, the appearance of Mo^5+ species in the XPS spectra indicated a photoreduction process in accordance with a photoinduced electron transfer mechanism.展开更多
基金Supported by the National Natural Science Foundation of China
文摘Two photochromic compounds with the pyrazolonering as the photochromic functional structure, 2(1phenyl3methyl4benzoformylpyrazolone5)thiosemicarbazone(PMBPTSC) and 2(1phenyl3methyl4benzoformylpyrazolone5)smethylthiosemicarbazone(PMBPMTSC), were synthesized and characterized by elemental analysis, MS, IR spectra, NMR spectra. The crystal structure of the photocolored product of PMBPTSC was determined by single crystal XRD analysis. The results show that the photochromic phenomenon is due to the photoisomerization from enol form to keto form. Their photochromic properties were studied by powderUV reflectance spectra under the irradiation of 200—380 nm light. The firstorder rate constants of the photocoloring reaction were found to be 780×10 -3 s -1 for compound 1A and 103×10 -3 s -1 for compound 2A.
基金Construction of High-Level Teachers of Beijing Institute of Fashion Technology,China(No.BIFT201808)。
文摘Incorporation of photochromic compounds to the polymer through chemical bonding will result in an enhancement of photoactivity and stabilization of optical properties.Here,spiropyran(SP)was introduced into polyurethane(PU)through semi-continuous emulsion copolymerization to get waterborne polyurethane dispersion(SPU).Studies on photochromic properties by UV-vis technique demonstrated the absorption intensity increased with the increasing of SP concentration and the colorless film turned to purple under UV irradiation.The kinetics for ring-opening and ring-closing reaction against SP were both first order,but the rate constants decreased with the increasing of SP concentration.The prepared SPU films showed reasonable photostability and photoreversibility according to the convenient test methods under UV-vis irradiation.Temperature dependence studies demonstrated that the photobleaching rate increased at higher temperatures with the same SP concentration.The chemical combination between SP and isocyanate(NCO)end group of polyurethane was confirmed through swelling experiments.Morphology studies were conducted by scanning electron microscope(SEM)micrographs and showed good compatibility between SP and PU.
基金Application Fundamental and Advanced Technology Research Proposal Project of Tianjin,China(No.18JCZDJC38300)。
文摘Photochromic and photoluminescence materials show bright colors under different excitation conditions,and thus,these functional materials have been applied in many fields.Based on the photochromic and photoluminescence theories,a block copolymer,which could be directly processed into nanofibers by electrospinning,was successfully prepared through atom transfer radical polymerization(ATRP).To synthesize the block copolymer,a vinyl monomer containing a spiropyran unit was employed to prepare the photochromic chain segment,and a polymethyl methacrylate(PMMA)chain segment was introduced to improve the processability of the block copolymer.Acting as the photoluminescence unit,the rare earth complex was linked to the side chain through coordination bonding between the rare earth ions and the ester groups of PMMA.When the photochromic and photoluminescence block copolymer was exposed to different wavelengths of ultraviolet(UV)light and visible(Vis)light,it could show white,red,green,yellow,and blue-purple.These results provide the potential of the as-prepared photochromic and photoluminescence block copolymer for application in fibers and fabrics.
基金This work was supported by the Basic Research Project of Natural Science in Shaanxi Province(2019JM-485)National College Students'Innovation and Entrepreneurship Training Program(S202010708007).
文摘Transparent wood(TW)is a wood-based biomaterial with several advantages,such as high optical transmittance,low thermal conductivity,and tunable haze.TW is functionalized according to its transparency to broaden its applications in different fields.Several studies have examined wood functionalization in recent years;however,few studies have reported photochromic TW(PTW)for ultraviolet(UV)-shielding window applications.Herein,PTW was obtained by infiltrating the delignified wood template with photochromic silver bromide(AgBr)nanoparticles and a pre-polymerized methyl methacrylate(MMA)mixture solution.The obtained PTW can adjust the luminous flux on change in the color in the visible light region.The photochromic properties were examined,and the optical properties of the composites were characterized using UV-Vis spectrophotometry.Light transmittance of PTW was up to 86.5%at 800 nm before UV irradiation,and it decreased to 70.1%at 800 nm after UV irradiation,as the wood color changed from colorless to dark purple under UV irradiation.Thus,this work not only achieves high-value utilization of wood,but also produces a new material that can be used in varied fields,such as UV-shielding,energy saving,and smart building.
文摘Copper-cadmium halide doped photochromic glass coating on plate glass has been prepared by a sol-gel process. The sample shows reversible photochromic effect. The results of X-ray diffraction (XRD) and infrared (IR) spectrum investigations indicate that the photochromic phase of tile coating is CuBrxCl1-x, solid solution, and that the structure network of the coating is connected with the bonds of Si-O-Si, Si-O-B and Si-O-Al.
基金Project funded by the Russian Foundation for Basic Research,the Government of the Krasnoyarsk Territory and Krasnoyarsk Regional Fund of Science(Grant 18-42-243023)the RF Ministry of Science and Higher Education+1 种基金the State Contract with Siberian Federal University for Scientific Researchthe grant of the President of Russian Federation(agreement 075-15-2019-676)。
文摘We have studied the dynamic and static processes occurring in disordered multiparticle colloidal Ag aggregates with natural structure and affecting their plasmonic absorption spectra under pico-and nanosecond pulsed laser radiations, as well as the physical origin responsible for these processes. We have shown that depending on the duration of the laser pulse,the mechanisms of laser modification of such aggregates can be associated both with changes in the resonant properties of the particles due to their heating and melting(picosecond irradiation mode) and with the particle shifts in the resonant domains of the aggregates(nanosecond pulses) which depend on the wavelength, intensity, and polarization of the radiation.These mechanisms result in formation of a narrow dip in the plasmonic absorption spectrum of the aggregates near the laser radiation wavelength and affect the shape and position of the dip. The effect of polydispersity of nanoparticle aggregates on laser photochromic reaction has been studied.
文摘In this paper, the influence of heat treatmenton transmittance and the photochromic of ion exchange pho-tochromic glass was studied, the microstructure of glass aswell as the forming of AgX crystals were discussed. It is be-lieved that heat treatment temperature affects precipitating ofAgX crystal .and the AgX crystal is a dominant factor af-fecting surface photochromic properties of ion exchange pho-tochromic glass.
文摘The photochromic properties of photochromicglasses containing both copper halides and cadmiumhalides depend mainly upon the body glass composi-tion. The composition range of glass matrix can bedescribed by F=[(R<sub>2</sub>0+MO)-Al<sub>2</sub>0<sub>3</sub>]/B<sub>2</sub>0<sub>3</sub>·In this paper,the basic structure of the glasses is investigatedin terms of IR and Raman spectroscopy in detail.The results demonstrate that the network of bodyglass is constructed by [SiO<sub>4</sub>], [BO<sub>3</sub>], [BO<sub>4</sub>] and[Al0<sub>4</sub>], in which [BO<sub>3</sub>] and [BO<sub>4</sub>] are interconnec-ted into two kinds of borate groups and a kind ofboroxol ring. Finally, the relationships betweenstructure and properties have been discussed on thescale of molecules and molecular groups.
文摘We successfully synthesized dithienylethene with amino groups. Then, we successfully prepared Langmuir-Blodgett (LB) films of the dithienylethene having ammonium cation group when dodecyl benzene sulfonic acid was employed as an anionic counter ion. From X-ray diffraction profiles, however, it was demonstrated that they did not form well-defined layered structure;X-ray diffraction peaks were much broadened. Photochromic behavior was confirmed in the LB films. Unfortunately, the LB films were not so stable;photochromic reaction was observed only several times in the LB films.
文摘Fulgide 1-E doped in polystyrene polymer films was heated at various annealing temperatures.Upon irradiation with UV light(366 nm),fulgide 1-E undergoes a conrotatory ring closure to the pink colored closed form 1-C.The later color was switched back to the original color when the films were irradiated with white light.The kinetics of photocoloration and photobleaching processes were followed spectrophotometrically by monitoring the absorbance of the ring closed product 1-C at itsλ_(max) of 525 nm.The fir...
基金financially supported by the National Natural Science Foundation Youth Fund of China(31800489)the Special Fund for Research on Scientific and Technological Innovation Talents in Harbin(2017RAQXJ092)+1 种基金Natural Science Foundation of Heilongjiang Province of China(LH2019E070)Postdoctoral Science Foundation funded project of Heilongjiang Province of China(LBH Z16007)。
文摘Photochromic wood was fabricated by coating microencapsulated photochromic material(MP)/polydimethylsiloxane composites onto wood using a simple drop-coating method.Urea-melamine–formaldehyde resin was used to microencapsulate the photochromic material(PM)via in situ polymerization.The concentration of the MP affected the photochromic property of the wood surface.The total color change(ΔE*)reached 82.2 when the concentration of the composite coating is 8%.Adhesion tests confirmed that the composite coating adhered firmly to the wood.This method is potentially useful for the production of functional wooden products,such as anti-counterfeiting materials and aesthetic wood.
文摘1, 2 - bis(3-Methylbenzo[b]thiophen-2-yl)cycloalkene derivatives 3a, 3b and 1- (2-methylbenzo[b]thiophen - 3 - yl ) - 2 - (3 - methylbenzo[b]thiophen - 2 - yl)cyclohexene 9 were synthesized. The obtained compounds exhibited photochromic property and the absorption bands of the colored forms 4a. 4b and 10 centered between 360-440 nm thus possessing the sensitivity at the wavelength of the newly developed InGaN diode laser.
文摘Photochromism is a phenomenon that a compound undergoes a reversible color change with the change of the wavelength of the irradiating light. Many photochromic compounds have been used in textiles as photochromic pigments.In this paper, some special techniques are used to prepare a photochromic compound of spirooxazines with an improved yield. Another photochromic spirooxazine with a sulfonate group which is soluble in water is also successfully synthesized. Tests are also conducted to find that they both display good photochromism in proper states.
基金Project supported by the National Natural Science Foundation of China(52062042,51802164)the Natural Science Foundation of Inner Mongolia(2020MS05044)。
文摘Photochromic materials with multicolor upconversion reversible modulations are attractive in optical switching devices.Herein,the fabricated YNbO_(4):Er^(3+)/Tm^(3+)/Yb^(3+) materials exhibit excellent photochromism and multicolor upconversion properties from green,red to near infrared(NIR) emissions with increasing Yb concentrations.Reversible multiband upconversion modulations are achieved by alternating light(365 and 405 nm) or thermal stimuli.After 365 nm irradiation,the luminescence color changes from yellow to red,the luminescent photoswitching contrast reaches up to 86.21%(green),82.12%(red) and 77.38%(NIR) in the Y_(0.83)Er_(0.01)Tm_(0.01)NbO_(4):0.15 Yb sample.Besides,the upconversion emission intensity before and after photochromic reaction shows remarkable change in a wide temperature range of 298-718 K.These results indicate that the Er^(3+)/Tm^(3+)/Yb^(3+) tri-doped YNbO_(4) materials can be a good candidate in optical switching and data storage applications.
文摘We herein present a simple,fast,low-temperature,post-glass melting fabrication protocol in which a photochromic silver cation based modified zone is incorporated within silver metaphosphate glass(AgPO_(3)).The selection of AgPO_(3)glass is mainly based on its relative“soft”nature(T_(g)=192℃)that enables the integration of silver cations from the surface deposited AgCl layer,while being transparent in most of the visible range,and therefore suitable for smart photochromic window applications.The suggested synthesis procedure permits the controlled formation of a silver cation modified layer within the host glass matrix,while the characteristics of the layer itself can be adjusted correspondingly.Our findings reveal a direct relationship between the developed composite AgCleAgPO_(3)glass photochromic response and the morphological features of the integrated layer,i.e.,thickness and position.More importantly,the photochromic response time with various UV irradiation doses is also studied,where remarkable response times of several seconds are obtained.Processes and efforts to further enhance the photochromic performance by utilizing the presence of silver nanoparticles within the glass matrix are also presented and discussed.
基金supported by the National Natural Science Foundation of China(Nos.51772326 and 62105235)Natural Science Foundation of Tianjin City(No.22JCZDJC00010)+1 种基金Tianjin Research Innovation Project for Postgraduate Students(No.2022SKY153)the National Undergraduate Training Programs for Innovation and Entrepreneurship(No.202210059005).
文摘Stimulus-responsive materials are fundamental to the broad and ever-growing field of intelligence research,which bridge intelligent systems with the Internet of Things(loT)in future lifestyles.Among these materials,writable materials have received great interest;however,carbonization and irreversible writing processes are generally inevitable for extensively investigated organic compounds.Photochromism is a potential mode of composing information.Nevertheless,inorganic materials usually exhibit weak photochromic effects.Here,a novel strategy of designing high-entropy perovskite(HEP)oxides is put forward to develop a new inorganic photochromic system with satisfying performance.A series of HEP oxides are synthesized for the first time.Benefiting from excellent photochromic features,real-time information encoding was achieved.The mechanism-related photochromism is also discussed.Distinct from the previous works,it is believed that the present photochromic-based HEP oxides provide a new and manyfold research space for the future development of conventional writable materials and the disclosing of unprecedented properties and phenomena.
基金financial support from the Natural Science Foundation of Henan Province(No.222300420501)the Science and Technology Project of Henan Province(No.212102210549)+1 种基金the Key Scientific Research Project of Higher Education of Henan Province(No.22A430007)National College Students Innovation and Entrepreneurship Training Program(No.202110482010)。
文摘Three novel dithienylethenes modified by bifluoroboron β-diketonate fragments have been successfully developed. Upon blue light irradiation, they reached photostationary state within 2-5 s, as well as 100% conversion ratio and photocyclization quantum yield of > 0.70. Such fascinating photochromism were endowed by collaborative role of electron-withdrawing effect of BF_(2)bdk group to reduce HOMO-LUMO electronic gap for the open isomer, together with intramolecular hydrogen bonds and CH-π interactions favoring antiparallel conformation fixation. Moreover, they displayed specific discrimination and photoswitchable bacterial imaging for S. aureus.
基金the region Grand-Est and FEDER funds for their support through a postdoctoral fellowship.
文摘Here,we report the ability of spiropyrans to initiate two-photon polymerization(TPP)for the first time in the literature.The comparison and synergies between the spiropyran photochromic molecule of interest,namely 6-nitro-BIPS,and well-known photoinitiators of radical photopolymerization have been studied.The spiropyran(SPy)molecule can initiate TPP in the presence of trifunctional acrylic monomers and create true 3D structures.The comparison with Irgacure 819,a well-known Type-I photoinitiator,shows that SPy has a comparable capability for TPP.In addition,the combination of SPy with methyl diethanolamine increased the reactivity of both one-and two-photon polymerizations.In the last section,we discuss which SPy isomer is the active photochromic species capable of generating radicals for initiating two-photon polymerization.
基金This work was supported by the National Key Basic Research Project (Grant No. G19990330).
文摘We introduce a high-density three-dimensional optical data storage approach by using a pyrryl-sub-stituted fulgide photochromic material with a method of single-beam two-photon recording and fluorescence confocal readout. The detailed information about the photochromic material and the experimental setup are presented. The experiments about multi-layered recording and readout are carried out with a 100-μm-thick transparent photochromic material film. The results show that the lateral resolution is better than 1 μm, and the longitudinal resolution is about 3 μm. Besides, the readout times for the recorded data aredesirable when using a readout laser power smaller than 5 mW.
基金supported by the National Natural Science Foundation of China (No.61774073)Open Project of State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, Jilin University (No. 2016-25)Science and Technology Development Program of Jilin province (No. 20170101086JC)
文摘TiO2 nanotube arrays were prepared by means of an electrochemical anodization technique in an organic electrolyte solution doped with polyvinyl pyrrolidone (PVP) and were subsequently modified with phosphomolybdic acid (PMoA) to obtain PMoA/TiO2 nanotube arrays. The microstructure and photochromic properties were investigated via X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), ultraviolet-visible spectroscopy (UV-vis), and X-ray photoelectron spectroscopy (XPS). The results indicated that the Keggin structure of PMoA and the nanotube structure of TiO2 were not destroyed, and there was a strong degree of interaction between PMoA and TiO2 at the biphasic interface with lattice interlacing during the compositing process. The XPS results further indicated that there was a change in the chemical microenvironment during the formation process of the composite, and a new charge transfer bridge was formed through the Mo-O-Ti bond. Under visible light irradiation, the colorless PMoA/TiO2 nanotube array quickly turned blue and exhibited a photochromic response together with reversible photochromism in the presence of H2O2. After visible light irradiation for 60s, the appearance of Mo^5+ species in the XPS spectra indicated a photoreduction process in accordance with a photoinduced electron transfer mechanism.