Lanthanide ions(Ln^(3+))doping provides a potential strategy to control over the luminescent properties of lead-free halide double perovskite nanocrystals(DP NCs).However,due to the low energy transfer efficiency betw...Lanthanide ions(Ln^(3+))doping provides a potential strategy to control over the luminescent properties of lead-free halide double perovskite nanocrystals(DP NCs).However,due to the low energy transfer efficiency between self-trapped exciton(STE)and Ln^(3+)ions,the characteristic emissions of Ln^(3+)ions are not prominent.Furthermore,the energy transfer mechanism between STE and Ln^(3+)ions is also elusive and requires in-depth study.We chose trace Bi^(3+)-doped Cs_(2)Ag_(0.6)Na_(0.4)InCl_(6-x)Br_(x) as a representative DP matrix to demonstrate that by tuning the bromide concentration,the Ln^(3+)emission can be greatly enhanced.Such enhanced STE and Ln^(3+)ions energy transfer originates from the high covalency of Ln-Br bond,which contributes to improve ment of the characteristic emission of Ln^(3+)ions.Furthermo re,optical spectroscopy reveals that the energy transfer mechanism from DP to Eu^(3+)ions is different from all the other doped Ln^(3+)ions.The energy transfer from DP to Eu^(3+)ions is mostly through Eu-Br charge transfer while the other Ln^(3+)ions are excited by energy transfer from STE.The distinct energy transfer mechanism has resulted from the energy separation between the excited energy level of Ln^(3+)ions and the bottom of conduction band of DP.With increasing the energy separation,the energy transfer from STE to Ln^(3+)ions is less efficient because of the generation of a larger number of phonons and finally becomes impossible for Eu^(3+)ions.Our results provide new insight into tuning the energy transfer of Ln^(3+)-doped DP NCs.展开更多
Persistent luminescence is a unique optical phenomenon that continues to emit light for minutes or even hours after the excitation stops,which can significantly enhance the sensitivity and signal-to-noise ratio of ima...Persistent luminescence is a unique optical phenomenon that continues to emit light for minutes or even hours after the excitation stops,which can significantly enhance the sensitivity and signal-to-noise ratio of imaging[1].Among numerous persistent luminescence materials,lanthanide-doped fluoride nanoparticles have shown tunable persistent luminescence across the UV-vis-NIR spectrum(200-1700 nm)under X-ray excitation and adjustable size,promising significant applications in deep-tissue imaging[2,3],security encryption,and data storage[4].In particular,those exhibiting NIR-II luminescence(1000-1700 nm)provide key advantages such as deeper tissue penetration,higher contrast,and minimal interference from biological autofluorescence.However,challenges such as low brightness and rapid signal decay,especially in the NIR-II region,limit their effectiveness in long-term monitoring,including tumor theranostics[5].Traditional approaches like size control and surface passivation yield only marginal improvements,underscoring the need for next-generation nanoparticles with superior NIR-II brightness.展开更多
Peroxynitrite(ONOO^(-))is a highly reactive nitrogen species that plays pivotal roles in cell signal transduction and physiological or pathological progresses.However,commonly used ONOO^(-)optical imaging probes are s...Peroxynitrite(ONOO^(-))is a highly reactive nitrogen species that plays pivotal roles in cell signal transduction and physiological or pathological progresses.However,commonly used ONOO^(-)optical imaging probes are still hampered by high background/autofluorescence(fluorescence probe),short emission wavelength,or poor selectivity in the case of chemiluminescence.Herein,we report a facile method to prepare an activatable chemiluminescence probe(PPA-PEG)with good biocompatibility and functionality for in vivo autofluorescence-free imaging of ONOO^(-).The PPA-PEG consists of pyropheophorbide-a(PPA),a typical deep red photosensitizer that acts as both the recognition and signaling element,and 4-arm poly(ethylene glycol)(4-arm PEG),which improves the biosafety and water solubility of probe.These components can self-assemble into nanoparticles(namely PPA-PEG nanoprobe)in aqueous solution.The PPA-PEG nanoprobe showed an ultra-low chemiluminescence signal before interacting with ONOO^(-),but exhibited good selectivity,high sensitivity and a fast response toward ONOO^(-).The PPAPEG was successfully applied to image cellular ONOO^(-)changes,as well as the endogenous ONOO^(-)changes in inflammation models and subcutaneous or orthotopic hepatocellular carcinoma(HCC)tumors models in living mice.In vitro and in vivo studies verified the good detection and imaging capabilities of PPA-PEG for peroxynitrite,demonstrating suitable tissue penetration and a high signal-to-background ratio(SBR).Thus,our nanoprobe can serve as a valuable activatable chemiluminescence imaging tool for studying important peroxynitrite-related chemical and biological applications.展开更多
Circularly polarized luminescence(CPL)has attracted growing attention for their promising applications in chiral functional devices.Achieving CPL materials with both high luminescence dissymmetry factors(g_(lum))and e...Circularly polarized luminescence(CPL)has attracted growing attention for their promising applications in chiral functional devices.Achieving CPL materials with both high luminescence dissymmetry factors(g_(lum))and emission efficiency is attractive but remains great challenges.In this study,a pair of chiral Cu(Ⅰ)complexes named R/S-CuI with C_(2) symmetry were synthesized,exhibiting no emission in solution and weak CPL with g_(lum)=±3.3×10^(-3)in crystalline state.Transparent chiral films(R/S-CuI-film)were developed through the co-assembly of R/S-CuI and achiral polymer PMMA.The films show bright green luminescence with the quantum yields about 200 times higher than those in crystalline state.Meanwhile,the maximum|g_(lum)|value is also amplified by approximately 2.5 times,reaching to 8.7×10^(-3).Mechanism investigation suggests that the notable enhancement of luminescence efficiency can be ascribed to the restriction of the intramolecular motions and the elimination of the oxygen quenching effect,while the improvement in g_(lum)values may be explained by the chirality transfer from the axially chiral molecule R/S-CuI to the achiral polymer PMMA.Furthermore,R/S-CuI-film were used for advanced information encryption applications based on its CPL characteristics.This work may provide new inspirations for the construction of CPL-active films with high performance,thereby expediting their further development.展开更多
The widespread applications of lanthanide-doped materials have fuelled a growing demand for precise control over the luminescence characteristics of these materials.However,the limitation imposed by concentration quen...The widespread applications of lanthanide-doped materials have fuelled a growing demand for precise control over the luminescence characteristics of these materials.However,the limitation imposed by concentration quenching remains a major obstacle in achieving efficient luminescence from lanthanide-doped materials.Herein,a novel strategy utilizing Sc_(2)O_(3):Ln^(3+) microflowers to enable confined energy migration in both microscopic quasi-zero-dimensional(0D)and mesoscopic twodimensional(2D)multi-coupling systems is proposed to overcome the concentration quenching limit of lanthanide emitters and achieve a remarkable doping amount of 48.14%on a single particle without resorting to complex core/multishell structure.Mechanistic studies reveal that the multi-confinement structure effectively restricts the range of energy migration and significantly reduces excitation energy migration to defects.Based on these highly doped Sc_(2)O_(3) microflowers,full spectrum and power-dependent tunable multi-color lanthanide emission in a single particle is successfully achieved.Furthermore,the 2D-encoded patterns derived from these microflowers hold great promise for anti-counterfeiting applications.Our findings emphasize the multi-coupling of confined quasi-0D&2D energy migration within a well-designed structure,providing valuable insights into concentration quenching mechanisms.This also opens up new opportunities for multi-level anti-counterfeiting systems and information security.展开更多
Polarized-light photodetectors are the indispensable elements for practical optical and optoelectronic device applications.Two-dimensional(2D)hybrid perovskite ferroelectrics,in which the coupling of spontaneous polar...Polarized-light photodetectors are the indispensable elements for practical optical and optoelectronic device applications.Two-dimensional(2D)hybrid perovskite ferroelectrics,in which the coupling of spontaneous polarization(P_(s))and light favors the dissociation of photo-induced carriers,have taken a booming position within this portfolio.However,polarized-light photodetectors with a low detectionlimit remain unexplored in this 2D ferroelectric family.In this work,the high-quality individual crystals of a 2D perovskite ferroelectric,BA_(2)CsPb_(2)Br_(7)(1,where BA^(+)is n-butylammonium),were used to fabricate ultrasensitive polarized-light detectors.Its unique bilayered structural motif results in quite strong electric and optical anisotropy with a large absorption ratio of a_(c)/α_(a)≈3.2(λ=405 nm).Besides,the presence of ferroelectric Psalso endows high built-in electric field along the polar c-axis that favors photoelectric activities.Under an extremely low detectable limit of 40 n W/cm^(2),the detector of 1 exhibits a notable dichroism ratio(I_(ph)^(c)/I_(ph)^(a)≈1.5),a large responsivity of~39.5 m A/W and a specific detectivity of~1.2×10^(12)Jones.Moreover,crystal-based devices of 1 also exhibit a fast response speed(~300μs)and excellent anti-fatigue merits.This work highlights great potentials of hybrid perovskite ferroelectrics toward polarized-light photodetection.展开更多
Birefringence arises when the propagation speed and refractive index of light in an optically anisotropic crystal changes in response to the direction of vibration.Thus,birefringence belongs to linear optical anisotro...Birefringence arises when the propagation speed and refractive index of light in an optically anisotropic crystal changes in response to the direction of vibration.Thus,birefringence belongs to linear optical anisotropy and is a key parameter for linear optoelectronic functional crystals,such as birefringent crystals,which are widely used to modulate the polarization of light in optoelectronic areas[1].In terms of practical applications,there is still an urgent need for wide-bandgap birefringent crystals as they allow for the modulation of light polarization in short-wavelength UV waves and even in the deep-UV spectral region.展开更多
A microporous supramolecular framework with high water and thermal stability can selectively absorb water molecules over methanol or ethanol due to the suitable channels.The model separation test on columns shows that...A microporous supramolecular framework with high water and thermal stability can selectively absorb water molecules over methanol or ethanol due to the suitable channels.The model separation test on columns shows that an ultra-pure ethanol(99.9%)can be obtained from the mixture of ethanol/water(95:5).Additionally,after refluxing the desolvated sample in 95%ethanol at 60℃for 5 h,the purity of ethanol rises up to 97.43%,which is obviously higher than 96.56%for 4 A molecular sieves.展开更多
Porous supramolecular frameworks based on metal-organic cages(MOCs)usually have poor structural stability after activation.This issue narrows the scope of their potential applications,particularly for the inclusion of...Porous supramolecular frameworks based on metal-organic cages(MOCs)usually have poor structural stability after activation.This issue narrows the scope of their potential applications,particularly for the inclusion of vip molecules that demand high porosity.Herein,the authors have reported the stabilization of a mesoporous zirconium MOC-based supramolecular framework with an in situ catalytic polymerization strategy.Due to the passivation effect imparted by this strategy,the introduced polymer is primarily distributed on the surface of the crystals,which results in the hybrid material retaining its crystallinity and permanent porosity.A preliminary application of this type of stabilized mesoporous supramolecular framework shows that among MOC-based supramolecular frameworks,it has the highest high-pressure methane uptake.Such a facile strategy may provide a general way to stabilize fragile porous materials and facilitate exploration of their potential applications.展开更多
Two novel 3D metal-organic frameworks(MOFs)with cds network,{[Me NH_3]_7[Ln_8(Pg C_2)_2(H_2O)_y(HCOO)_7]}_n·x(Solvent)(FJI-Y4,FJI=Fujian Institute,Ln=Gd,y=12;FJI-Y5,Ln=Dy,y=11;Pg C_2=C-ethylpyrogallol[4]arene),ba...Two novel 3D metal-organic frameworks(MOFs)with cds network,{[Me NH_3]_7[Ln_8(Pg C_2)_2(H_2O)_y(HCOO)_7]}_n·x(Solvent)(FJI-Y4,FJI=Fujian Institute,Ln=Gd,y=12;FJI-Y5,Ln=Dy,y=11;Pg C_2=C-ethylpyrogallol[4]arene),based on unprecedented dimeric pyrogallol[4]arene-based Ln_8metal-organic nanocapsule(MONC)supramolecular building blocks and formate linkers,have been prepared under solvothermal conditions.To our best of knowledge,they present not only the first two examples of 3D hierarchical structures constructed from MONCs in metal-pyrogallol[4]arene system,but also the first two examples of MOFs based on lanthanide MONCs.Remarkably,the inner cavity volume of the Ln_8capsule in FJI-Y4 and FJI-Y5 is approximately151?~3,which is larger than those found in previous transition metal-seamed dimeric Pg C_n-based MONCs.Magnetic investigation on FJI-Y4 suggests a significant magnetocaloric effect(23.97 J kg^(-1)K^(-1),ΔH=7 T,2.5 K),while FJI-Y5 exhibits slow relaxation of the magnetization.展开更多
Nonlinear optical(NLO)switchable materials have attracted intense attention because of their promising applications in optoelectronic devices.However,previous studies are mainly limited to molecular-based compounds th...Nonlinear optical(NLO)switchable materials have attracted intense attention because of their promising applications in optoelectronic devices.However,previous studies are mainly limited to molecular-based compounds that usually exhibit narrow bandgaps.Here,we report all-inorganic Li_(9)Na_(3)Rb_(2)(SO_(4))_(7) as an ultrawide-bandgap NLO switchable material.展开更多
Conventional wisdom says that nonpolar structures do not favorably produce strong second-harmonic generation(SHG)responses since the polarization in their microscopic functional groups are counteracted.Herein,we repor...Conventional wisdom says that nonpolar structures do not favorably produce strong second-harmonic generation(SHG)responses since the polarization in their microscopic functional groups are counteracted.Herein,we report the first nonlinear optical thiosulfate,Na_(10)Cd(NO_(3))_(4)(SO_(3)S)_(4),which crystallizes in a nonpolar space group of P−4.However,this thiosulfate exhibits a strong SHG response of about 4.2 times that of the benchmark KH2PO4,which is larger than those of polar sulfates.According to first-principles calculations and a flexible dipole model,the SHG enhancement is mainly ascribed to the larger flexibility of the S=S bond in the SO_(3)S tetrahedra in comparison with the S–O bond in the SO4 tetrahedra.These findings indicate that constructing flexible bonds is an effective strategy to design highperformance nonlinear optical materials regardless of polarity.展开更多
Self-trapped excitons(STEs)emission from halide perovskites with strong exciton-phonon coupling has attracted considerable attention due to the widespread application in optoelectronic devices.Nevertheless,the in-dept...Self-trapped excitons(STEs)emission from halide perovskites with strong exciton-phonon coupling has attracted considerable attention due to the widespread application in optoelectronic devices.Nevertheless,the in-depth understanding of the relationship between exciton-phonon coupling and luminescence intensity remains incomplete.Herein,a doping-enhanced exciton-phonon coupling effect is observed in Cs_(3)Cu_(2)I_(5)nanocrystals(NCs),which leads to a remarkable increasement of their STEs emission efficiency.Mechanism study shows that the hetero-valent substitution of Cu+with alkaline-earth metal ions(AE^(2+))causes a greater degree of Jahn-Teller distortion between the ground state and excited state structures of[Cu_(2)I_(5)]_(3)-clusters as evidenced by our spectral analysis and first-principles calculations.As a consequence,an X-ray detector based on these Cs_(3)Cu_(2)I_(5):AE NCs delivers an X-ray imaging resolution of up to 10 lp·mm^(-1) and a low detection limit of 0.37μGyair·s^(-1),disclosing the potential of doping-enhanced exciton-phonon coupling effect in improving STEs-emission and practical application for X-ray imaging.展开更多
The practical application of all-inorganic semiconductor lead halide perovskite nanocrystals(LHP NCs)has been limited by their poor stability.Recently,a lot of research on core-shell structure has been done to improve...The practical application of all-inorganic semiconductor lead halide perovskite nanocrystals(LHP NCs)has been limited by their poor stability.Recently,a lot of research on core-shell structure has been done to improve the stability of perovskite NCs,but the effect was far from the application requirements.Herein,we,for the first time,report a convenient approach to synthesize organic-inorganic double shell CsPbBr_(3)@SiO_(2)@polystyrene(PS)NCs with an inter-core of CsPbBr_(3),the intermediate layer of SiO_(2)shell,and outmost PS shell.Particularly,the CsPbBr_(3)@SiO_(2)@PS NCs maintained more than 90%of their initial photoluminescence(PL)intensity under one month's ultraviolet lamp irradiation or in 85℃ and 85%relative humidity(RH)condition.The white-light-emitting-diodes(WLEDs)were fabricated by encapsulating commercial InGaN chip with CsPbBr_(3)@SiO_(2)@PS NCs and K2SiF6:Mn^(4+)(KSF:Mn^(4+))phosphor with a luminous efficacy of~100 lm/W at 20 mA current and a color gamut of 128%of the National Television Standards Committee(NTSC)standard.In addition,these WLEDs still maintain 91%of the initial luminous efficacy after 1200 h of continuous lighting.These results demonstrated that double shell-protected CsPbBr_(3)perovskite NCs have great potential in the field of WLEDs.展开更多
Rapid halide anion exchange easily occurring in metal-halide perovskite nanoparticles(NPs)makes it nearly impossible to create a single three-dimensional(3D)CsPbX_(3)(X=Cl,Br,I)NP that simultaneously comprises two sep...Rapid halide anion exchange easily occurring in metal-halide perovskite nanoparticles(NPs)makes it nearly impossible to create a single three-dimensional(3D)CsPbX_(3)(X=Cl,Br,I)NP that simultaneously comprises two separate perovskite components.To circumvent this problem,we first propose a Ni^(2+)-mediated halide anion-exchange strategy in zero-dimensional(0D)Ni^(2+)-doped Cs_(4)PbBr_(6)(Cs_(4)PbBr_(6):Ni)perovskites to achieve ultra-stable 3D CsPbX_(3)NPs with two coexisting different perovskite individuals of CsPbCl_(3)and/or CsPbBr_(3).By combining the experimental results with first-principles calculations,we confirm that the completely isolated[PbBr_(6)]4−octahedra in 0D Cs_(4)PbBr_(6):Ni NPs can restrict rapid halide anion exchange and the anion diffusion preferentially proceeds in the proximity of substitutional NiPb centers,namely[NiBr_(6)]4−octahedra in a meta-stable state,rather than in the 0D Cs_(4)PbBr_(6)and residual 3D CsPbBr_(3)regions,thereby delivering intrinsic dual-band excitonic luminescence from a single 3D CsPbX_(3)NP with a more stable and efficient CsPbCl_(3)component as compared to its counterparts synthesized using conventional methods.These new insights regarding the precise control of halide anion exchange enable the preparation of a new type of high-efficiency perovskite materials with suppressed anion interdiffusion for prospective optoelectronic devices.展开更多
The crystalline sponge method is a pragmatic and promising strategy for molecular structure determination.However,the dominant metal-organic framework crystal sponge platforms always face poor chemical stability,espec...The crystalline sponge method is a pragmatic and promising strategy for molecular structure determination.However,the dominant metal-organic framework crystal sponge platforms always face poor chemical stability,especially solvent instability,hampering their application in a vaster domain.Herein,we report an ultrastable π-π stacked porous organic molecular framework which exhibits permanent porosity,high thermal stability,and good chemical resistance.It can efficiently implement an approach to molecular structure determination via a single-crystal-to-single-crystal transformation.This is the first example utilizing π-π stacked porous organic molecular framework as“crystalline sponge”to determine a wide variety of vips,ranging from hydrophilic to hydrophobic,and from aliphatic to aromatic,which complements the crystalline sponges based on the famous metal-organic frameworks.More importantly,it can achieve rapid structure determination of small molecules within 3 h.展开更多
The design and synthesis of stable metal–organic frameworks(MOFs)have been a core obstacle in the widespread application of these functional crystalline porous materials,because of the stability limitations of MOFs u...The design and synthesis of stable metal–organic frameworks(MOFs)have been a core obstacle in the widespread application of these functional crystalline porous materials,because of the stability limitations of MOFs under harsh operating conditions.Herein,a highly stable microporous MOF based on the Fe_(3)O cluster(PCN-678)has been synthesized using a tetracarboxylate ligand.Utilizing symmetry reduced tetratopic carboxylate ligand,a mesoporous MOF(PCN-668)could be obtained in which nanoscale cage-like building units and one-dimensional(1D)channels coexist.The neighboring cages were mutual diastereomers in PCN-668 due to the further reduction of the Cs symmetry of the free ligand to C1 symmetry after self-assembly.Furthermore,the acid stability of this mesoporous MOF was improved via postsynthetic metal exchange to chromium(PCN-668-Cr).The PCN-668-Cr exhibited very high stability in both acidic and basic aqueous solutions(pH=1–11).Additionally,the mesoporous MOF showed a high total gravimetric methane uptake(∼500 cm^(3) g^(−1) at 100 bar),while the microporous MOF showed a high volumetric methane storage capacity of 147 cm3 cm−3 at room temperature.展开更多
Hexagonal-phase NaYF_(4)(β-NaYF_(4))has been acknowledged to be one of the most efficient doping hosts to prepare bright lanthanide-doped luminescent nano-bioprobes for various biomedical applications.However,to date...Hexagonal-phase NaYF_(4)(β-NaYF_(4))has been acknowledged to be one of the most efficient doping hosts to prepare bright lanthanide-doped luminescent nano-bioprobes for various biomedical applications.However,to date,it remains a great challenge to synthesize ultra-bright lanthanide-dopedβ-NaYF_(4)nano-bioprobes under a low reaction temperature by using conventional synthetic methods.Herein,we first develop an acetic acid(HAc)-mediated coprecipitation method for the preparation of ultrabright lanthanide-dopedβ-NaYF_(4)nanoprobes under a low reaction temperature at 200℃.Based on a series of comparative spectroscopic investigations,we show that the use of HAc in the reaction environment can not only promote the rapidα-βphase transformation of NaYF_(4)host at 200℃ within 1 h but also boost the absolute photoluminescence quantum yield(PLQY)of NaYF_(4)nanocrystals to 30.68%for near-infrared emission and to 3.79%for upconversion luminescence,both of which are amongst the highest values for diverse lanthanide-doped luminescent nanocrystals ever reported.By virtue of their superior nearinfrared luminescence,we achieve optical-guided dynamic vasculature imaging in vivo of the whole body at a high spatial resolution(23.8μm)under 980 nm excitation,indicating its potential for the diagnosis and treatment evaluation of vasculaturerelated diseases.展开更多
Trivalent lanthanide(Ln^(3+))-doped luminescent nanoparticles(NPs)have been extensively investigated as deep-tissue-penetration visual bioimaging agents owing to their exceptional upconversion and near-infrared(NIR)lu...Trivalent lanthanide(Ln^(3+))-doped luminescent nanoparticles(NPs)have been extensively investigated as deep-tissue-penetration visual bioimaging agents owing to their exceptional upconversion and near-infrared(NIR)luminescence upon irradiation of NIR light.However,in most cases,the power density of irradiation used for in vivo biological imaging is much higher than that of the reported maximum permissible exposure(MPE)value of NIR light,which inevitably does great damage to the living organisms under study and thus impedes the plausible clinical applications.Herein,by using a facile syringe pump-aided shell epitaxial growth method,we construct for the first time a new class of Ln^(3+)-doped KMgF_(3):Yb/Er@KMgF_(3)core-shell NPs that can be activated by utilizing a 980-nm xenon lamp or diode laser with an ultralow excitation power density down to 0.08 mW cm^(−2),a value that is approximately 4 orders of magnitude lower than the MPE value set by the American National Standards Institute(ANSI)for safe bioimaging in vivo.By combining the comparative spectroscopic investigations with atomic-resolved spherical aberration corrected transmission electron microscopy(AC-TEM)characterization,we find that the reduced crystallographic defects are the primary cause underlying such an ultralow-power-excitable feature of the KMgF_(3):Yb/Er@KMgF_(3)core-shell NPs.And,by the same token,the resultant KMgF_(3):Yb/Er@KMgF_(3)core-shell NPs also exhibit an anomalous thermo-enhanced photoluminescence(PL)behavior coupled with an excellent photothermal stability that cannot occur in other Ln^(3+)-doped core-shell NPs.These findings described here unambiguously pave a new way to prepare high-quality Ln^(3+)-doped luminescent NPs with desirable ultralow-power-excitable capability and photothermal stability for future biomedical applications.展开更多
As structural variants of famous hexagonal tungsten bronzes,hexagonal tungsten oxides(HTO)represent an important family with fascinating functional properties,such as piezoelectric,ferroelectric,pyroelectric,and nonli...As structural variants of famous hexagonal tungsten bronzes,hexagonal tungsten oxides(HTO)represent an important family with fascinating functional properties,such as piezoelectric,ferroelectric,pyroelectric,and nonlinear optical(NLO)properties.However,none of them are transparent in the deep-UV spectral region,which limits their applications.Herein,we report the first HTO-type monofluorophosphate K_(3)Sc_(3)(PO_(4))(PO_(3)F)_(2)F_(5)(I)with deep-UV transparency.Such a monofluorophosphate is NLO-active with a phase-matchable powder second harmonic generation efficiency of 0.9 times that of KH_(2)PO_(4)at 1,064 nm.Importantly,the UV-Vis reflectance spectrum indicates that it is deep-UV transparent down to 200 nm.This work pushes the transparent window of NLO materials with HTO-type structures down to the deep-UV spectral region for the first time and opens up a new door for HTO materials.展开更多
基金Project supported by the Research Project of Mindu Innovation Laboratory(2021ZZ114)Natural Science Foundation of Xiamen(3502Z20227255)+1 种基金Major Research Project of Xiamen(3502Z20191015)the Science and Technology Major Project of Fujian Province(2021HZ021013)。
文摘Lanthanide ions(Ln^(3+))doping provides a potential strategy to control over the luminescent properties of lead-free halide double perovskite nanocrystals(DP NCs).However,due to the low energy transfer efficiency between self-trapped exciton(STE)and Ln^(3+)ions,the characteristic emissions of Ln^(3+)ions are not prominent.Furthermore,the energy transfer mechanism between STE and Ln^(3+)ions is also elusive and requires in-depth study.We chose trace Bi^(3+)-doped Cs_(2)Ag_(0.6)Na_(0.4)InCl_(6-x)Br_(x) as a representative DP matrix to demonstrate that by tuning the bromide concentration,the Ln^(3+)emission can be greatly enhanced.Such enhanced STE and Ln^(3+)ions energy transfer originates from the high covalency of Ln-Br bond,which contributes to improve ment of the characteristic emission of Ln^(3+)ions.Furthermo re,optical spectroscopy reveals that the energy transfer mechanism from DP to Eu^(3+)ions is different from all the other doped Ln^(3+)ions.The energy transfer from DP to Eu^(3+)ions is mostly through Eu-Br charge transfer while the other Ln^(3+)ions are excited by energy transfer from STE.The distinct energy transfer mechanism has resulted from the energy separation between the excited energy level of Ln^(3+)ions and the bottom of conduction band of DP.With increasing the energy separation,the energy transfer from STE to Ln^(3+)ions is less efficient because of the generation of a larger number of phonons and finally becomes impossible for Eu^(3+)ions.Our results provide new insight into tuning the energy transfer of Ln^(3+)-doped DP NCs.
基金supported by the Major Research Plan of the National Natural Science Foundation of China(No.92361202)National Natural Science Foundation of China(No.12204481).
文摘Persistent luminescence is a unique optical phenomenon that continues to emit light for minutes or even hours after the excitation stops,which can significantly enhance the sensitivity and signal-to-noise ratio of imaging[1].Among numerous persistent luminescence materials,lanthanide-doped fluoride nanoparticles have shown tunable persistent luminescence across the UV-vis-NIR spectrum(200-1700 nm)under X-ray excitation and adjustable size,promising significant applications in deep-tissue imaging[2,3],security encryption,and data storage[4].In particular,those exhibiting NIR-II luminescence(1000-1700 nm)provide key advantages such as deeper tissue penetration,higher contrast,and minimal interference from biological autofluorescence.However,challenges such as low brightness and rapid signal decay,especially in the NIR-II region,limit their effectiveness in long-term monitoring,including tumor theranostics[5].Traditional approaches like size control and surface passivation yield only marginal improvements,underscoring the need for next-generation nanoparticles with superior NIR-II brightness.
基金supported by the Major Research Projects for Young and Middle-aged Talent of Fujian Provincial Health Commission(2021ZQNZD013)the Medical Innovation Project of Fujian Province(2021CXA043)+4 种基金the National Natural Science Foundation of China(62275050,62175031,and 22274023)the Natural Science Foundation of Fujian Province(2023J05093 and 2024J011224)the Scientific Foundation of Fuzhou Municipal Health Commission(2022-S-wt3),the Scientific Foundation of Fuzhou Municipal Health Commission(2022-S-rc1),the Scientific Foundation of Fuzhou Municipal Health Commission(2021-S-wp1)the Fujian Provincial Clinical Research Center for Hepatobiliary and Pancreatic Tumors(2020Y2013)the Fuzhou“14th Five-Year”Clinical Key Specialty(20220203)。
文摘Peroxynitrite(ONOO^(-))is a highly reactive nitrogen species that plays pivotal roles in cell signal transduction and physiological or pathological progresses.However,commonly used ONOO^(-)optical imaging probes are still hampered by high background/autofluorescence(fluorescence probe),short emission wavelength,or poor selectivity in the case of chemiluminescence.Herein,we report a facile method to prepare an activatable chemiluminescence probe(PPA-PEG)with good biocompatibility and functionality for in vivo autofluorescence-free imaging of ONOO^(-).The PPA-PEG consists of pyropheophorbide-a(PPA),a typical deep red photosensitizer that acts as both the recognition and signaling element,and 4-arm poly(ethylene glycol)(4-arm PEG),which improves the biosafety and water solubility of probe.These components can self-assemble into nanoparticles(namely PPA-PEG nanoprobe)in aqueous solution.The PPA-PEG nanoprobe showed an ultra-low chemiluminescence signal before interacting with ONOO^(-),but exhibited good selectivity,high sensitivity and a fast response toward ONOO^(-).The PPAPEG was successfully applied to image cellular ONOO^(-)changes,as well as the endogenous ONOO^(-)changes in inflammation models and subcutaneous or orthotopic hepatocellular carcinoma(HCC)tumors models in living mice.In vitro and in vivo studies verified the good detection and imaging capabilities of PPA-PEG for peroxynitrite,demonstrating suitable tissue penetration and a high signal-to-background ratio(SBR).Thus,our nanoprobe can serve as a valuable activatable chemiluminescence imaging tool for studying important peroxynitrite-related chemical and biological applications.
基金supported by the National Key Research and Development Program of China (2018YFA0704502 and 2019YFA0210402)National Natural Science Foundation of China (22271280,22101047,and 21921001)the Natural Science Foundation of Fujian Province (2020J05064)。
文摘Circularly polarized luminescence(CPL)has attracted growing attention for their promising applications in chiral functional devices.Achieving CPL materials with both high luminescence dissymmetry factors(g_(lum))and emission efficiency is attractive but remains great challenges.In this study,a pair of chiral Cu(Ⅰ)complexes named R/S-CuI with C_(2) symmetry were synthesized,exhibiting no emission in solution and weak CPL with g_(lum)=±3.3×10^(-3)in crystalline state.Transparent chiral films(R/S-CuI-film)were developed through the co-assembly of R/S-CuI and achiral polymer PMMA.The films show bright green luminescence with the quantum yields about 200 times higher than those in crystalline state.Meanwhile,the maximum|g_(lum)|value is also amplified by approximately 2.5 times,reaching to 8.7×10^(-3).Mechanism investigation suggests that the notable enhancement of luminescence efficiency can be ascribed to the restriction of the intramolecular motions and the elimination of the oxygen quenching effect,while the improvement in g_(lum)values may be explained by the chirality transfer from the axially chiral molecule R/S-CuI to the achiral polymer PMMA.Furthermore,R/S-CuI-film were used for advanced information encryption applications based on its CPL characteristics.This work may provide new inspirations for the construction of CPL-active films with high performance,thereby expediting their further development.
基金supported by the National Natural Science Foundation of China(92361202,12204481)the Fund of Fujian Science&Technology Innovation Laboratory for Optoelectronic Information(2020ZZ114,2022ZZ204)+3 种基金the China Postdoctoral Science Foundation(2023M733498,2024T170925)the Natural Science Foundation of Fujian Province(2022J05102)the National Key Research and Development Program of China(2022YFB3503704)the Self-deployment Project Research Program of Haixi Institutes,Chinese Academy of Sciences(CXZX-2022-GS01).
文摘The widespread applications of lanthanide-doped materials have fuelled a growing demand for precise control over the luminescence characteristics of these materials.However,the limitation imposed by concentration quenching remains a major obstacle in achieving efficient luminescence from lanthanide-doped materials.Herein,a novel strategy utilizing Sc_(2)O_(3):Ln^(3+) microflowers to enable confined energy migration in both microscopic quasi-zero-dimensional(0D)and mesoscopic twodimensional(2D)multi-coupling systems is proposed to overcome the concentration quenching limit of lanthanide emitters and achieve a remarkable doping amount of 48.14%on a single particle without resorting to complex core/multishell structure.Mechanistic studies reveal that the multi-confinement structure effectively restricts the range of energy migration and significantly reduces excitation energy migration to defects.Based on these highly doped Sc_(2)O_(3) microflowers,full spectrum and power-dependent tunable multi-color lanthanide emission in a single particle is successfully achieved.Furthermore,the 2D-encoded patterns derived from these microflowers hold great promise for anti-counterfeiting applications.Our findings emphasize the multi-coupling of confined quasi-0D&2D energy migration within a well-designed structure,providing valuable insights into concentration quenching mechanisms.This also opens up new opportunities for multi-level anti-counterfeiting systems and information security.
基金supported by the National Natural Science Foundation of China(21622108,21875251,21525104,and 21833010)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB20010200)Youth Innovation Promotion of Chinese Academy of Sciences。
文摘Polarized-light photodetectors are the indispensable elements for practical optical and optoelectronic device applications.Two-dimensional(2D)hybrid perovskite ferroelectrics,in which the coupling of spontaneous polarization(P_(s))and light favors the dissociation of photo-induced carriers,have taken a booming position within this portfolio.However,polarized-light photodetectors with a low detectionlimit remain unexplored in this 2D ferroelectric family.In this work,the high-quality individual crystals of a 2D perovskite ferroelectric,BA_(2)CsPb_(2)Br_(7)(1,where BA^(+)is n-butylammonium),were used to fabricate ultrasensitive polarized-light detectors.Its unique bilayered structural motif results in quite strong electric and optical anisotropy with a large absorption ratio of a_(c)/α_(a)≈3.2(λ=405 nm).Besides,the presence of ferroelectric Psalso endows high built-in electric field along the polar c-axis that favors photoelectric activities.Under an extremely low detectable limit of 40 n W/cm^(2),the detector of 1 exhibits a notable dichroism ratio(I_(ph)^(c)/I_(ph)^(a)≈1.5),a large responsivity of~39.5 m A/W and a specific detectivity of~1.2×10^(12)Jones.Moreover,crystal-based devices of 1 also exhibit a fast response speed(~300μs)and excellent anti-fatigue merits.This work highlights great potentials of hybrid perovskite ferroelectrics toward polarized-light photodetection.
基金supported by the National Natural Science Foundation of China(21833010,22193042,22125110,21921001,22122507,61975207,and U21A2069)the Youth Innovation Promotion of Chinese Academy of Sciences(Y202069)+5 种基金the Natural Science Foundation of Fujian Province(2021J01523 and2022J02012)the Key Research Program of Frontier Sciences of the Chinese Academy of Sciences(ZDBS-LY-SLH024)Fujian Institute of Innovation in Chinese Academy of Sciences(FJCXY18010201)Young Talent Supporting Project of Fujian Association of Science and Technology(2021000008)the National Postdoctoral Program for Innovative Talents(BX2021315)the National Key Research and Development Program of China(2019YFA0210402).
文摘Birefringence arises when the propagation speed and refractive index of light in an optically anisotropic crystal changes in response to the direction of vibration.Thus,birefringence belongs to linear optical anisotropy and is a key parameter for linear optoelectronic functional crystals,such as birefringent crystals,which are widely used to modulate the polarization of light in optoelectronic areas[1].In terms of practical applications,there is still an urgent need for wide-bandgap birefringent crystals as they allow for the modulation of light polarization in short-wavelength UV waves and even in the deep-UV spectral region.
基金support from the National Key Research and Development Program of China(No.2017YFA0700102)the National Natural Science Foundation of China(Nos.21871266 and 21731006)+1 种基金the Key Research Program of Frontier Science CAS(No.QYZDY-SSW-SLH025)Youth Innovation Promotion Association CAS.
文摘A microporous supramolecular framework with high water and thermal stability can selectively absorb water molecules over methanol or ethanol due to the suitable channels.The model separation test on columns shows that an ultra-pure ethanol(99.9%)can be obtained from the mixture of ethanol/water(95:5).Additionally,after refluxing the desolvated sample in 95%ethanol at 60℃for 5 h,the purity of ethanol rises up to 97.43%,which is obviously higher than 96.56%for 4 A molecular sieves.
基金This study was financially supported by the National Nature Science Foundation of China(nos.21771177 and 51603206)the Strategic Priority Research Program of CAS(no.XDB20000000)the Key Research Program of Frontier Sciences,CAS(no.QYZDB-SSW-SLH019).
文摘Porous supramolecular frameworks based on metal-organic cages(MOCs)usually have poor structural stability after activation.This issue narrows the scope of their potential applications,particularly for the inclusion of vip molecules that demand high porosity.Herein,the authors have reported the stabilization of a mesoporous zirconium MOC-based supramolecular framework with an in situ catalytic polymerization strategy.Due to the passivation effect imparted by this strategy,the introduced polymer is primarily distributed on the surface of the crystals,which results in the hybrid material retaining its crystallinity and permanent porosity.A preliminary application of this type of stabilized mesoporous supramolecular framework shows that among MOC-based supramolecular frameworks,it has the highest high-pressure methane uptake.Such a facile strategy may provide a general way to stabilize fragile porous materials and facilitate exploration of their potential applications.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB20000000)the National Natural Science Foundation of China (21390392, 51603206)the Nature Science Foundation of Fujian Province (2016J05056)
文摘Two novel 3D metal-organic frameworks(MOFs)with cds network,{[Me NH_3]_7[Ln_8(Pg C_2)_2(H_2O)_y(HCOO)_7]}_n·x(Solvent)(FJI-Y4,FJI=Fujian Institute,Ln=Gd,y=12;FJI-Y5,Ln=Dy,y=11;Pg C_2=C-ethylpyrogallol[4]arene),based on unprecedented dimeric pyrogallol[4]arene-based Ln_8metal-organic nanocapsule(MONC)supramolecular building blocks and formate linkers,have been prepared under solvothermal conditions.To our best of knowledge,they present not only the first two examples of 3D hierarchical structures constructed from MONCs in metal-pyrogallol[4]arene system,but also the first two examples of MOFs based on lanthanide MONCs.Remarkably,the inner cavity volume of the Ln_8capsule in FJI-Y4 and FJI-Y5 is approximately151?~3,which is larger than those found in previous transition metal-seamed dimeric Pg C_n-based MONCs.Magnetic investigation on FJI-Y4 suggests a significant magnetocaloric effect(23.97 J kg^(-1)K^(-1),ΔH=7 T,2.5 K),while FJI-Y5 exhibits slow relaxation of the magnetization.
基金supported by the National Nature Science Foundation of China(21833010,61975207,21622101,21921001,21525104,and 51662013)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB20000000 and XDB20010200)+5 种基金the Natural Science Foundation of Fujian Province(2018H0047)the Key Research Program of Frontier Sciences of the Chinese Academy of Sciences(ZDBS-LY-SLH024)the Natural Science Foundation of Guangxi Province(2018GXNSFDA281015)the National Key Research and Development Program of China(2019YFA0210400)Key Laboratory of Functional Crystals and Laser Technology,TIPC,CAS(FCLT 202003)Key Laboratory of New Processing Technology for Nonferrous Metal&Materials,Ministry of Education/Guangxi Key Laboratory of Optical and Electronic Materials and Devices(20KF-11).
文摘Nonlinear optical(NLO)switchable materials have attracted intense attention because of their promising applications in optoelectronic devices.However,previous studies are mainly limited to molecular-based compounds that usually exhibit narrow bandgaps.Here,we report all-inorganic Li_(9)Na_(3)Rb_(2)(SO_(4))_(7) as an ultrawide-bandgap NLO switchable material.
基金supported by the National Natural Science Foundation of China(nos.21833010,61975207,21921001,21971238,51872297,and 51890864)the Key Research Program of Frontier Sciences of the Chinese Academy of Sciences(no.ZDBS-LY-SLH024)+3 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(nos.XDB20010200 and XDB20000000)Fujian Institute of Innovation(no.FJCXY18010201)in Chinese Academy of Sciences,the National Key Research and Development Program of China(no.2019YFA0210400)Key Laboratory of Functional Crystals and Laser Tech-nology,TIPC,CAS(no.FCLT 202003)as well as Key Laboratory of New Processing Technology for Nonferrous Metal&Materials,Ministry of Education/Guangxi Key Laboratory of Optical and Electronic Materials and Devices(no.20KF-11).
文摘Conventional wisdom says that nonpolar structures do not favorably produce strong second-harmonic generation(SHG)responses since the polarization in their microscopic functional groups are counteracted.Herein,we report the first nonlinear optical thiosulfate,Na_(10)Cd(NO_(3))_(4)(SO_(3)S)_(4),which crystallizes in a nonpolar space group of P−4.However,this thiosulfate exhibits a strong SHG response of about 4.2 times that of the benchmark KH2PO4,which is larger than those of polar sulfates.According to first-principles calculations and a flexible dipole model,the SHG enhancement is mainly ascribed to the larger flexibility of the S=S bond in the SO_(3)S tetrahedra in comparison with the S–O bond in the SO4 tetrahedra.These findings indicate that constructing flexible bonds is an effective strategy to design highperformance nonlinear optical materials regardless of polarity.
基金This work is supported by the Fund of Fujian Science&Technology Innovation Laboratory for Optoelectronic Information(Nos.2020ZZ114 and 2022ZZ204)the Key Research Program of Frontier Science CAS(No.QYZDY-SSW-SLH025)+1 种基金the National Natural Science Foundation of China(Nos.21731006 and 21871256)the Fund of Advanced Energy Science and Technology Guangdong Laboratory(No.DJLTN0200/DJLTN0240).
文摘Self-trapped excitons(STEs)emission from halide perovskites with strong exciton-phonon coupling has attracted considerable attention due to the widespread application in optoelectronic devices.Nevertheless,the in-depth understanding of the relationship between exciton-phonon coupling and luminescence intensity remains incomplete.Herein,a doping-enhanced exciton-phonon coupling effect is observed in Cs_(3)Cu_(2)I_(5)nanocrystals(NCs),which leads to a remarkable increasement of their STEs emission efficiency.Mechanism study shows that the hetero-valent substitution of Cu+with alkaline-earth metal ions(AE^(2+))causes a greater degree of Jahn-Teller distortion between the ground state and excited state structures of[Cu_(2)I_(5)]_(3)-clusters as evidenced by our spectral analysis and first-principles calculations.As a consequence,an X-ray detector based on these Cs_(3)Cu_(2)I_(5):AE NCs delivers an X-ray imaging resolution of up to 10 lp·mm^(-1) and a low detection limit of 0.37μGyair·s^(-1),disclosing the potential of doping-enhanced exciton-phonon coupling effect in improving STEs-emission and practical application for X-ray imaging.
基金This work was supported by the Priority Research Project of Xiamen(No.3502Z20191015)the Science and Technology Major Project of Fujian Province(No.2021HZ021013)the Major Research Project of Mindu Innovation Laboratory(No.2021ZZ114).
文摘The practical application of all-inorganic semiconductor lead halide perovskite nanocrystals(LHP NCs)has been limited by their poor stability.Recently,a lot of research on core-shell structure has been done to improve the stability of perovskite NCs,but the effect was far from the application requirements.Herein,we,for the first time,report a convenient approach to synthesize organic-inorganic double shell CsPbBr_(3)@SiO_(2)@polystyrene(PS)NCs with an inter-core of CsPbBr_(3),the intermediate layer of SiO_(2)shell,and outmost PS shell.Particularly,the CsPbBr_(3)@SiO_(2)@PS NCs maintained more than 90%of their initial photoluminescence(PL)intensity under one month's ultraviolet lamp irradiation or in 85℃ and 85%relative humidity(RH)condition.The white-light-emitting-diodes(WLEDs)were fabricated by encapsulating commercial InGaN chip with CsPbBr_(3)@SiO_(2)@PS NCs and K2SiF6:Mn^(4+)(KSF:Mn^(4+))phosphor with a luminous efficacy of~100 lm/W at 20 mA current and a color gamut of 128%of the National Television Standards Committee(NTSC)standard.In addition,these WLEDs still maintain 91%of the initial luminous efficacy after 1200 h of continuous lighting.These results demonstrated that double shell-protected CsPbBr_(3)perovskite NCs have great potential in the field of WLEDs.
基金supported by the Fund of Fujian Science&Technology Innovation Laboratory for Optoelectronic Information(grant nos.2020ZZ114 and 2022ZZ204)the Key Research Program of Frontier Science CAS(grant no.QYZDY-SSW-SLH025)+1 种基金the National Natural Science Foundation of China(grant nos.21731006 and 21871256)the Fund of Advanced Energy Science and Technology Guangdong Laboratory(grant no.DJLTN0200/DJLTN0240).
文摘Rapid halide anion exchange easily occurring in metal-halide perovskite nanoparticles(NPs)makes it nearly impossible to create a single three-dimensional(3D)CsPbX_(3)(X=Cl,Br,I)NP that simultaneously comprises two separate perovskite components.To circumvent this problem,we first propose a Ni^(2+)-mediated halide anion-exchange strategy in zero-dimensional(0D)Ni^(2+)-doped Cs_(4)PbBr_(6)(Cs_(4)PbBr_(6):Ni)perovskites to achieve ultra-stable 3D CsPbX_(3)NPs with two coexisting different perovskite individuals of CsPbCl_(3)and/or CsPbBr_(3).By combining the experimental results with first-principles calculations,we confirm that the completely isolated[PbBr_(6)]4−octahedra in 0D Cs_(4)PbBr_(6):Ni NPs can restrict rapid halide anion exchange and the anion diffusion preferentially proceeds in the proximity of substitutional NiPb centers,namely[NiBr_(6)]4−octahedra in a meta-stable state,rather than in the 0D Cs_(4)PbBr_(6)and residual 3D CsPbBr_(3)regions,thereby delivering intrinsic dual-band excitonic luminescence from a single 3D CsPbX_(3)NP with a more stable and efficient CsPbCl_(3)component as compared to its counterparts synthesized using conventional methods.These new insights regarding the precise control of halide anion exchange enable the preparation of a new type of high-efficiency perovskite materials with suppressed anion interdiffusion for prospective optoelectronic devices.
基金supported by the National Nature Science Foundation of China(grant nos.21871266,21731006,and 21403241)the Strategic Priority Research Program of the Chinese Academy of Sciences(grant no.XDB20000000)+1 种基金Key Research Program of Frontier Science CAS(grant no.QYZDY-SSW-SLH025)Youth Innovation Promotion Association CAS.
文摘The crystalline sponge method is a pragmatic and promising strategy for molecular structure determination.However,the dominant metal-organic framework crystal sponge platforms always face poor chemical stability,especially solvent instability,hampering their application in a vaster domain.Herein,we report an ultrastable π-π stacked porous organic molecular framework which exhibits permanent porosity,high thermal stability,and good chemical resistance.It can efficiently implement an approach to molecular structure determination via a single-crystal-to-single-crystal transformation.This is the first example utilizing π-π stacked porous organic molecular framework as“crystalline sponge”to determine a wide variety of vips,ranging from hydrophilic to hydrophobic,and from aliphatic to aromatic,which complements the crystalline sponges based on the famous metal-organic frameworks.More importantly,it can achieve rapid structure determination of small molecules within 3 h.
基金supported by the Center for Gas Separations,an Energy Frontier Research Center funded by the U.S.Department of Energy,Office of Science,Office of Basic Energy Sciences(no.DESC0001015)Structural analyses were supported by the Robert A.Welch Foundation through a Welch Endowed Chair to H.-C.Z.(A-0030)+3 种基金The National Science Foundation Graduate Research Fellowship(DGE:1252521)is gratefully acknowledged.The authors also acknowledge the financial support of the U.S.Department of Energy Office of Fossil Energy,National Energy Technology Laboratory(no.DE-FE0026472)and National Science Foundation Small Business Innovation Research(NSFSBIR)under grant no.(1632486)the financial support of the Strategic Priority Research Program of the Chinese Academy of Sciences(no.XDB20000000)National Nature Science Foundation of China(no.21871266),CAS(no.QYZDY-SSWSLH025),and Youth Innovation Promotion Association CAS.
文摘The design and synthesis of stable metal–organic frameworks(MOFs)have been a core obstacle in the widespread application of these functional crystalline porous materials,because of the stability limitations of MOFs under harsh operating conditions.Herein,a highly stable microporous MOF based on the Fe_(3)O cluster(PCN-678)has been synthesized using a tetracarboxylate ligand.Utilizing symmetry reduced tetratopic carboxylate ligand,a mesoporous MOF(PCN-668)could be obtained in which nanoscale cage-like building units and one-dimensional(1D)channels coexist.The neighboring cages were mutual diastereomers in PCN-668 due to the further reduction of the Cs symmetry of the free ligand to C1 symmetry after self-assembly.Furthermore,the acid stability of this mesoporous MOF was improved via postsynthetic metal exchange to chromium(PCN-668-Cr).The PCN-668-Cr exhibited very high stability in both acidic and basic aqueous solutions(pH=1–11).Additionally,the mesoporous MOF showed a high total gravimetric methane uptake(∼500 cm^(3) g^(−1) at 100 bar),while the microporous MOF showed a high volumetric methane storage capacity of 147 cm3 cm−3 at room temperature.
基金This work was supported by the Fund of Fujian Science&Technology Innovation Laboratory for Optoelectronic Information(No.2020ZZ114)the Key Research Program of Frontier Science CAS(No.QYZDY-SSW-SLH025)+2 种基金the National Natural Science Foundation of China(Nos.21871256 and 12204481)the Natural Science Foundation of Fujian Province(No.2022J01211422)Fund of Advanced Energy Science and Technology Guangdong Laboratory(No.DJLTN0200/DJLTN0240).
文摘Hexagonal-phase NaYF_(4)(β-NaYF_(4))has been acknowledged to be one of the most efficient doping hosts to prepare bright lanthanide-doped luminescent nano-bioprobes for various biomedical applications.However,to date,it remains a great challenge to synthesize ultra-bright lanthanide-dopedβ-NaYF_(4)nano-bioprobes under a low reaction temperature by using conventional synthetic methods.Herein,we first develop an acetic acid(HAc)-mediated coprecipitation method for the preparation of ultrabright lanthanide-dopedβ-NaYF_(4)nanoprobes under a low reaction temperature at 200℃.Based on a series of comparative spectroscopic investigations,we show that the use of HAc in the reaction environment can not only promote the rapidα-βphase transformation of NaYF_(4)host at 200℃ within 1 h but also boost the absolute photoluminescence quantum yield(PLQY)of NaYF_(4)nanocrystals to 30.68%for near-infrared emission and to 3.79%for upconversion luminescence,both of which are amongst the highest values for diverse lanthanide-doped luminescent nanocrystals ever reported.By virtue of their superior nearinfrared luminescence,we achieve optical-guided dynamic vasculature imaging in vivo of the whole body at a high spatial resolution(23.8μm)under 980 nm excitation,indicating its potential for the diagnosis and treatment evaluation of vasculaturerelated diseases.
基金supported by the Fund of Fujian Science&Technology Innovation Laboratory for Optoelectronic Information(2020ZZ114)the Key Research Program of Frontier Science CAS(QYZDY-SSW-SLH025)+1 种基金the National Natural Science Foundation of China(21731006 and 21871256)the Fund of Advanced Energy Science and Technology Guangdong Laboratory(DJLTN0200/DJLTN0240)。
文摘Trivalent lanthanide(Ln^(3+))-doped luminescent nanoparticles(NPs)have been extensively investigated as deep-tissue-penetration visual bioimaging agents owing to their exceptional upconversion and near-infrared(NIR)luminescence upon irradiation of NIR light.However,in most cases,the power density of irradiation used for in vivo biological imaging is much higher than that of the reported maximum permissible exposure(MPE)value of NIR light,which inevitably does great damage to the living organisms under study and thus impedes the plausible clinical applications.Herein,by using a facile syringe pump-aided shell epitaxial growth method,we construct for the first time a new class of Ln^(3+)-doped KMgF_(3):Yb/Er@KMgF_(3)core-shell NPs that can be activated by utilizing a 980-nm xenon lamp or diode laser with an ultralow excitation power density down to 0.08 mW cm^(−2),a value that is approximately 4 orders of magnitude lower than the MPE value set by the American National Standards Institute(ANSI)for safe bioimaging in vivo.By combining the comparative spectroscopic investigations with atomic-resolved spherical aberration corrected transmission electron microscopy(AC-TEM)characterization,we find that the reduced crystallographic defects are the primary cause underlying such an ultralow-power-excitable feature of the KMgF_(3):Yb/Er@KMgF_(3)core-shell NPs.And,by the same token,the resultant KMgF_(3):Yb/Er@KMgF_(3)core-shell NPs also exhibit an anomalous thermo-enhanced photoluminescence(PL)behavior coupled with an excellent photothermal stability that cannot occur in other Ln^(3+)-doped core-shell NPs.These findings described here unambiguously pave a new way to prepare high-quality Ln^(3+)-doped luminescent NPs with desirable ultralow-power-excitable capability and photothermal stability for future biomedical applications.
基金supported by the NSFC(21833010,61975207,21921001,21971238,51872297,and 51890864)Youth Innovation Promotion of CAS(202069)+6 种基金the Key Research Program of Frontier Sciences of the Chinese Academy of Sciences(ZDBS-LYSLH024)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB20010200 and XDB20000000)Fujian Institute of Innovation(FJCXY18010201)in Chinese Academy of Sciencesthe National Key Research and Development Program of China(2019YFA0210400)Key Laboratory of Functional Crystals and Laser Technology,TIPC,CAS(FCLT 202003)Key Laboratory of New Processing Technology for Nonferrous Metal&Materials,Ministry of Education/Guangxi Key Laboratory of Optical and Electronic Materials and Devices(20KF-11)Startup Project of Doctor Scientific Research of Jiangxi Normal University(12021319)。
文摘As structural variants of famous hexagonal tungsten bronzes,hexagonal tungsten oxides(HTO)represent an important family with fascinating functional properties,such as piezoelectric,ferroelectric,pyroelectric,and nonlinear optical(NLO)properties.However,none of them are transparent in the deep-UV spectral region,which limits their applications.Herein,we report the first HTO-type monofluorophosphate K_(3)Sc_(3)(PO_(4))(PO_(3)F)_(2)F_(5)(I)with deep-UV transparency.Such a monofluorophosphate is NLO-active with a phase-matchable powder second harmonic generation efficiency of 0.9 times that of KH_(2)PO_(4)at 1,064 nm.Importantly,the UV-Vis reflectance spectrum indicates that it is deep-UV transparent down to 200 nm.This work pushes the transparent window of NLO materials with HTO-type structures down to the deep-UV spectral region for the first time and opens up a new door for HTO materials.
