Mixed-lanthanide(Ln) luminescent materials have important application values in ratiometric temperature sensing.Hydrogen-bonded organic frameworks(HOFs) offer a self-supporting network to conveniently tune multiple Ln...Mixed-lanthanide(Ln) luminescent materials have important application values in ratiometric temperature sensing.Hydrogen-bonded organic frameworks(HOFs) offer a self-supporting network to conveniently tune multiple Ln^(3+)ions,but challenges still exist in material design.In this work,we selected two simple organic molecules as hydrogen-bonded building blocks,which are melamine(MA) and 2,5-pyridinedicarboxylic acid(PDC) owning the suitable energy to sensitize Tb^(3+)and Eu^(3+)ions.MA assists PDC molecules to support the network in a new HOF(MA-PDC),where the abundant carboxylic groups enable Ln^(3+)ions to combine with the HOF.Based on the effective energy transfer process,the emission of Tb^(3+)and Eu^(3+)from TbxEu1-x@MA-PDC(x=0.75,0.85,0.90) shows the obvious temperature dependence,which benefits ratiometric temperature detection.Taking Tb0.85Eu0.15@MA-PDC as an example,when temperature varies from 303 to 443 K,the intensity ratio exhibits distinct S-type response based on Mott-Seitz model.It also behaves good relative sensitivity(1.03%/K at 383 K),low temperature resolution(0.059 K) and large reproducibility(>96%).This work demonstrates that functionalization of a simple-component HOF with mixed Ln^(3+)ions is a fantastic strategy to develop novel ratiometric thermometers of both low cost and good performance.展开更多
Sorption of lanthanum（Ⅲ）, cerium（Ⅲ and neodymium（Ⅲ） ions from the aqueous solutions of mixtures through adsorption on the biochar composites was investigated as a function of sorbent mass, pH, phase contact ti...Sorption of lanthanum（Ⅲ）, cerium（Ⅲ and neodymium（Ⅲ） ions from the aqueous solutions of mixtures through adsorption on the biochar composites was investigated as a function of sorbent mass, pH, phase contact time and initial concentration of solutions at 295 K. The maximum removal of lanthanide ions takes place under the following conditions： 0.1 g of sorbent mass, pH 4 and 360 rain contact time for all studied initial concentrations of solutions. Kinetics of La（Ⅲ）, Ce（Ⅲ） and Nd（Ⅲ） ions sorption proceeded by a fast initial uptake reached equilibrium. This process was modelled by means of the pseudo first order, pseudo second order, intraparticle diffusion and Elovich models. The desorption of three lanthahide ions by nitric, hydrochloric and sulfuric acids at a concentration of 1 mol/L from biochar composites was also studied. In order to investigate the sorption mechanism FFIR, XRD and XPS analyses were performed after sorption of ions from the mixture.展开更多
The luminescence from lanthanide ions has potential applications in light emitting diodes,biomedical,solar cells,sensors,display,etc.However,the luminescence is suffered from the various problems,such as low luminesce...The luminescence from lanthanide ions has potential applications in light emitting diodes,biomedical,solar cells,sensors,display,etc.However,the luminescence is suffered from the various problems,such as low luminescence efficiency and inharmonious wavelength for energy transfer.Magnetic field is an efficient method to modulate the wavelength and intensity of luminescence from lanthanide ions.Magnetic field redistributes the populated electrons in the excited states to tune the wavelength of lanthanide ions by Zeeman effect,mixing effect,and quantum confinement effect.Magnetic field enhances or suppresses the luminescence intensity by the administration of cross-relaxation,energy transfer,and Boltzmann population.In this review,we first introduce the various phenomena and mechanisms of magnetic field modulated downshift luminescence from lanthanide ions,including Zeeman effect,cross-relaxation,crystal structure,absorption,quantum confinement effect,and magneticoptical hysteresis.Then,we explain the regulation of upconversion luminescence by magnetic field,containing energy transfer and mixing effect.Finally,different options regarding how to understand the mechanism of magnetic field-modulated luminescence from lanthanide ions in the future are outlined.展开更多
Ultrathin TiO_(2)nanosheets with coexposed{001}/{101}facets have attracted considerable attention because of their high photocatalytic activity.However,the charge-separated states in the TiO_(2)nanosheets must be exte...Ultrathin TiO_(2)nanosheets with coexposed{001}/{101}facets have attracted considerable attention because of their high photocatalytic activity.However,the charge-separated states in the TiO_(2)nanosheets must be extended to further enhance their photocatalytic activity for H_(2)evolution.Herein,we present a successful attempt to selectively dope lanthanide ions into the{101}facets of ultrathin TiO_(2)nanosheets with coexposed{001}/{101}facets through a facile one-step solvothermal method.The lanthanide doping slightly extended the light-harvesting region and markedly improved the charge-separated states of the TiO_(2)nanosheets as evidenced by UV-vis absorption and steady-state/transient photoluminescence spectra.Upon simulated sunlight irradiation,we observed a 4.2-fold enhancement in the photocatalytic H_(2)evolution activity of optimal Yb^(3+)-doped TiO_(2)nanosheets compared to that of their undoped counterparts.Furthermore,when Pt nanoparticles were used as cocatalysts to reduce the H_(2)overpotential in this system,the photocatalytic activity enhancement factor increased to 8.5.By combining these results with those of control experiments,we confirmed that the extended charge-separated states play the main role in the enhancement of the photocatalytic H_(2)evolution activity of lanthanide-doped TiO_(2)nanosheets with coexposed{001}/{101}facets.展开更多
A series of seven novel lanthanide（Ⅲ ） nitrato complexes with 4-[ N-（2-methoxybenzylimine）formyl] 1-2, 3- dimethyl-1-phenyl-3-pyazolin-5-one （2mbfa）, were synthesized. These complexes were characterized by elem...A series of seven novel lanthanide（Ⅲ ） nitrato complexes with 4-[ N-（2-methoxybenzylimine）formyl] 1-2, 3- dimethyl-1-phenyl-3-pyazolin-5-one （2mbfa）, were synthesized. These complexes were characterized by elemental analysis, molecular mass determination, conductance and magnetic moment measurements, IR, UV-visible, and ^13CNMR spectral studies, In these complexes, the Schiff base, 2mbfa, acts as neutral bidentate ligand by utilizing the carbonyl oxygen and azomethine nitrogen as donor sites. All the three nitrate ions are also coordinated unidentately with 7 coordination for the lanthanide（Ⅲ） ions with a tentative monocapped octahedral geometry for the complexes. All the seven lanthanide（Ⅲ） complexes have a general formula, [ Ln（2mbfa）：（NO3）3 ].展开更多
Extractability and extraction mechanism of lanthanide ions were investigated by using a new extractant,N,Nn,N′,N′-tetrabutyl-3-oxa-diglycolamide(TBDGA),in toluene from nitric acid media.The effects of HNO_3 and TBDG...Extractability and extraction mechanism of lanthanide ions were investigated by using a new extractant,N,Nn,N′,N′-tetrabutyl-3-oxa-diglycolamide(TBDGA),in toluene from nitric acid media.The effects of HNO_3 and TBDGA concentrations,and temperature,on extraction of lanthanide ions were studied.Stoichiometrics of the main extracted species were HNO_3·TBDGA and M(NO_3)_3-3TBDGA(M = Er,Dy,Tb,Gd,La,Ce,Nd,Sm and Eu).The extracted species for metal ions were established to be ionic complex.In this complex,nitrate anion was not coordinated to the central ion.The extraction pattern increased gradually across the lanthanide ions series,showing enhanced affinity of TBDGA toward heavy lanthanide ions.Thermodynamic parameters were investigated for the exothermic extraction reaction.展开更多
Two new mononuclear lanthanide（Ⅲ） complexes Ln（pytz）3（H2O）3·（H2O）3.5[Ln=Tb（1）;Eu（2）;Hpytz=5-（2-pyridyl）tetrazole] were synthesized by reacting Hpytz with the corresponding lanthanide（Ⅲ） ions and...Two new mononuclear lanthanide（Ⅲ） complexes Ln（pytz）3（H2O）3·（H2O）3.5[Ln=Tb（1）;Eu（2）;Hpytz=5-（2-pyridyl）tetrazole] were synthesized by reacting Hpytz with the corresponding lanthanide（Ⅲ） ions and characterized.The single crystal X-ray diffraction analysis reveals that complexes 1 and 2 are isostructural and the lanthanide（Ⅲ） ions in both complexes 1 and 2 are nine-coordinated,with three oxygen atoms of three coordination water molecules and six nitrogen atoms of three pytz ligands,forming a monocapped square antiprism.Extensive hydrogen bonds exist,resulting in a three-dimensional supramolecular network structure by hydrogen-bonds in both complexes 1 and 2,respectively.Complex 1 exhibits typical green fluorescence of Tb（Ⅲ） ion and complex 2 red fluorescence of Eu（Ⅲ） ion,in solid state at room temperature.展开更多
A mixture containing eleven lanthanide ions was separated and detected on an anion exchange co lumn by ion chromatography with indirect photometry detection (IPC).An aqueous solution of 1.5×10 -2 mol/L ni...A mixture containing eleven lanthanide ions was separated and detected on an anion exchange co lumn by ion chromatography with indirect photometry detection (IPC).An aqueous solution of 1.5×10 -2 mol/L nitrilotri(methylenephosphonic) acid and 2.5×10 -3 mol/L tiron was used as the eluent in which the former served as complexing agent and eluent,the latter played as color reagent and eluent.The effects of acidity,concentration and composition of eluent on the retention behavior of the analytes and detection sensitivity are discussed.展开更多
Four kinds of lanthanide ions（Sm^3＋,Yb^3＋,Eu^3＋,La^3＋）as an additive were added into the aqueous solution containing methanol,respectively,and their effects on methanol elecotrooxidation in aqueous solutions wer...Four kinds of lanthanide ions（Sm^3＋,Yb^3＋,Eu^3＋,La^3＋）as an additive were added into the aqueous solution containing methanol,respectively,and their effects on methanol elecotrooxidation in aqueous solutions were studied with cyclic voltammetry.The results show that the four kinds of ions have promotion action upon the electrooxidation of methanol to different degrees.The best additive,Sm^3＋,can increase the anodic oxidation current of methanol by 80%and the peak potential shifted negatively about 50 mV.The promotion effects of the lanthanide ions were considered to be related to the extranuclear electron distribution of these ions and their adsorption on the Pt electrode surface.展开更多
The structure of phenylalanine transfer ribonucleic acid(tRNA Phe ) in solution was explored by 1 H NMR spectroscopy to evaluate the effect of lanthanide ion on the structural and conformational change. It w...The structure of phenylalanine transfer ribonucleic acid(tRNA Phe ) in solution was explored by 1 H NMR spectroscopy to evaluate the effect of lanthanide ion on the structural and conformational change. It was found that La 3+ ions possess specific effects on the imino proton region of the 1 H NMR spectra for yeast tRNA Phe . The dependence of the imino proton spectra of yeast tRNA Phe as a function of La 3+ concentration was examined, and the results suggest that the tertiary base pair G 15 ·C 48 , which is located in the terminal in the augmented dihydrouridine helix(D helix), was markedly affected by La 3+ (shifted to downfield by as much as 0 35). Base pair U 8·A 14 in yeast tRNA Phe , which are stacked on G 15 ·C 48 , was also affected by added La 3+ when 1～2 Mg 2+ were also present. Another imino proton that may be affected by La 3+ in yeast tRNA Phe is that of the tertiary base pair G 19 ·C 56 . The assignment of this resonance in yeast tRNA Phe is tentative since it is located in the region of highly overlapping resonances beween 12 6 and 12 2. This base pair helps to anchor the D loop to the TΨC loop. The binding of La 3+ caused conformational change of tRNA, which is responsible for shifts to upfield or downfield in 1 H NMR spectra.展开更多
Two isomorphous 2D zigzag-ladder structure coordination polymers containing coordination supramolecular capsules are reported,which are built by trivalent lanthanide ions,pyridine N-oxide（PNO） and p-sulfonatothiacal...Two isomorphous 2D zigzag-ladder structure coordination polymers containing coordination supramolecular capsules are reported,which are built by trivalent lanthanide ions,pyridine N-oxide（PNO） and p-sulfonatothiacalix[4]arene（H4TCAS4-）：[Ln2（PNO）2（H2O）10？（H2TCAS）2].[Ln2（H2TCAS）2（H2O）6（MeOH）2].2MeOH.12H2O（Ln = La,1;Nd,2）.Crystal data for complex 1：C31H51La2NO33S8,Mr = 1500.03,triclinic system,P 1 space group,with a = 11.732（2）,b = 15.007（3）,c = 15.262（3）,α = 78.05（3）,β = 80.77（3）,γ = 83.89（3）°,Z = 2,V = 2587.3（9）3,Dc = 1.925 g/cm3,μ = 2.051 mm-1,F（000） = 1500,the final R = 0.0300 and wR = 0.0823;and those for complex 2：C31H51Nd2NO33S8,Mr = 1510.69,triclinic system,P1 space group,with a = 11.719（2）,b = 14.941（3）,c = 15.157（3）,α = 78.03（3）,β = 80.84（3）,γ = 83.95（3）°,Z = 2,V = 2555.9（9）3,Dc = 1.963 g/cm3,μ = 2.436 mm-1,F（000） = 1512,the final R = 0.0493 and wR = 0.1267.There are two coordination environments of lanthanide ions.One is bridged by two PNO molecules forming a dimeric Ln ion in the O,O’-μ2 mode.The dinuclear ions are shrouded by two H2TCAS6-ions through coordination interactions and hydrogen bonds.The other coordination mode of Ln ions is a zigzag 1D chain linked by up-down H2TCAS6-ions.By the coordination capsules,the complexes form 2D zigzag-ladder structure coordination polymers.展开更多
The toxicity of lead ions has become the severe challenge for the all-inorganic lead halide p erovskite materials,although some works have rep orted the lead-free perovskite nanocrystals(NCs),the photoluminescence qua...The toxicity of lead ions has become the severe challenge for the all-inorganic lead halide p erovskite materials,although some works have rep orted the lead-free perovskite nanocrystals(NCs),the photoluminescence quantum yield(PLQY)of these materials is still unsatisfactory.Meanwhile,because the halogen ions can be easily exchanged,the controllable multicolor emission in perovskite NCs is difficult to realize in current reports.In this work,we introduced lanthanide ions into lead-free Cs_(3)Sb_(2)Cl_(9) perovskite NCs.Benefitting from the energy transfer between Cs_(3)Sb_(2)Cl_(9) perovskite NC host and lanthanide ions,the multicolor emission was realized.Based on controlling the doping concentration of Tb^(3+)and Eu^(3+)ions,the white light emission under UV excitation would be turned easily in the Tb^(3+)/Eu^(3+)codoped NCs.In addition,efficient energy transfer from perovskite NCs to Tb^(3+)or Eu^(3+)ions is beneficial to improving the optical properties of lead-free perovskite NCs,resulting in maximum PLQYs of red,green and white light emission of 22.6%,19.7%and 28.5%,respectively.Finally,a white light emitting device(WLED)was fabricated with a power efficiency of 18.5 lm/W,which presents the Commission Internationale de l'Eclairage(CIE)of(0.33,0.35).展开更多
Based on the completely parametric crystal-field model, the energy level parameters, including free-ion parameters and crystal-field parameters, obtained by fitting the experimental energy level data sets of Ln^（3＋...Based on the completely parametric crystal-field model, the energy level parameters, including free-ion parameters and crystal-field parameters, obtained by fitting the experimental energy level data sets of Ln^（3＋） in LiYF_4 were systematically analyzed. The results revealed that the regular variation trends of the major parameters at relatively low site symmetry still existed. The g factors of ground states were calculated using the parameters obtained from least-squares fitting. The results for Ce^（3＋）, Nd^（3＋）, Sm^（3＋）, Dy^（3＋） and Yb^（3＋） were in good agreement with experiment, while those of Er^（3＋） deviated from experiment dramatically. Further study showed that the g factors depended strongly on B_4~6, and a slightly different B_4~6 value of -580cm^（-1） led to g factors agreeing well with the experimental values.展开更多
The molecular interactions between Nd^(3+), Gd^(3+)and Yb^(3+) and DPPC in multibilayer have been studied by Fourier transform infrared spectroscopy. The results show that incorporations of the lanthanide ions conside...The molecular interactions between Nd^(3+), Gd^(3+)and Yb^(3+) and DPPC in multibilayer have been studied by Fourier transform infrared spectroscopy. The results show that incorporations of the lanthanide ions considerably shift the gel to liquid-crystal phase transition to higher temperatures. The incorporations of Gd^(3+) and Yb^(3+) obviously reduce the cooperations of the transition. The phosphate region of the spectra indicates that the Ln^(3+) binding to DPPC forms DPPC-Ln^(3+)complex and the Lna^(3+)binding is not dependent on the phase state of DPPC. The C-H stretching region of the spectra suggests that the incorporation of Ln^(3+)increases the conformational order of DPPC both in gel and in liquid-crystal phase as a result of the reduction of gauche rotamers.展开更多
The adsorption behavior and mechanism of Bi（Ⅲ） ions on the rutile-water interface were investigated through micro-flotation, Zeta potential measurement, adsorption amount measurement and X-ray photoelectron spectro...The adsorption behavior and mechanism of Bi（Ⅲ） ions on the rutile-water interface were investigated through micro-flotation, Zeta potential measurement, adsorption amount measurement and X-ray photoelectron spectroscopy（XPS）. According to the results of micro-flotation, Bi（Ⅲ） ions could largely improve the rutile flotation recovery（from 62% to 91%）, and they could increase the activating sites and reduce the competitive adsorption between nonyl hydroxamic acid negative ions and OH-ions, which determined that Bi（Ⅲ） ions were capable of activating rutile flotation. The adsorption of Bi（Ⅲ） ions onto the rutile surface led to the shift of Zeta potential into the positive direction, which was good for the adsorption of nonyl hydroxamic acid anions. In addition, the results of XPS indicated that the chemical environment around Ti atom had not changed before and after the adsorption of Bi（Ⅲ） ions. Based on the adsorption mechanism of Bi（Ⅲ） ions, it was deduced that firstly Bi（Ⅲ） ions occupied the vacancies of the original Ca^2＋, Mg^2＋ and Fe^2＋ ions on the rutile surface; secondly Bi（Ⅲ） ions covered on the rutile surface in the form of hydroxides.展开更多
The exploitation of a highly selective and sensitive probe to detect both cancer marker and metal ion is of great importance.In this work,the "one stone two bird" agent of 1,10-phenanthroline(phen) is design...The exploitation of a highly selective and sensitive probe to detect both cancer marker and metal ion is of great importance.In this work,the "one stone two bird" agent of 1,10-phenanthroline(phen) is designed to disrupt the polymeric lanthanide MOFs(LnMOFs,[Ln(CHO_(2))_(3)]n,Ln=Tb,la;Eu,1 b,CHO_(2)=formic acid) {[Ln(CHO_(2))_(4)·(C_(2) H_(8) N)]n,Ln=Y,2 a;Gd,2 b;Dy,2 c,C_(2)H_(8) N=dimethylamine}) into a soluble mononuclear species [Ln(phen)_(2)(NO_(3))_(3),Ln=Tb,3 a;Eu,3 b] as well as to provide an antenna for efficient photons absorption,resulting in an ultra-high luminescence quantum yield(QY,90%) europium complex.The luminescence QY is among the highest record of monomeric(zero-dimensional) lanthanide complexes.Furthermore,mononuclear Tb3+complex(3 a) functions as a multiplex sensor towards both Fe^(2+)and cancer marker of 5-hydroxyindole-3-acetic acid(5-HIAA).Importantly,the limit of detection(LOD)for sensing 5-HIAA is an ultra-sensitive value of 1 × 10 s mol/L,which is even lower than that necessary for the early diagnosis of carcinoid tumors.More interestingly,sensing results in simulated urine reveals that 3 a has potential application for early diagnosis in the clinic.展开更多
Xanthated crosslinked chitosan(XCCS) resin prepared under microwave irradiation were used for adsorbing Au(Ⅲ) ions in hydrochloric acid medium.The influence of pH and temperature on the adsorption capacity of XCCS wa...Xanthated crosslinked chitosan(XCCS) resin prepared under microwave irradiation were used for adsorbing Au(Ⅲ) ions in hydrochloric acid medium.The influence of pH and temperature on the adsorption capacity of XCCS was investigated.The original XCCS and the loaded XCCS were characterized by scanning electron microscope(SEM) and X-ray diffraction(XRD),respectively.The results indicate that the XCCS has ability to adsorb Au(Ⅲ) ions and the maximum adsorption capacity of Au(Ⅲ) ions on XCCS is observed at pH 1 and 20℃.The data of batch adsorption tests are fitted to kinetic models and isotherm models,respectively.The kinetics of adsorption process is found to follow pseudo-second-order kinetic rate model,and equilibrium data agree very well with the Langmuir model.Thermodynamic calculation of the Au(Ⅲ) ions adsorption process indicates that the adsorption process is spontaneous and endothermic.展开更多
A fluorescence-enhanced probe PY, which is based on integration of pyrene moiety and amino acid group,was developed for the orthogonal recognition of In3＋ and Al3＋ by the quick formation of 1：1 complex. PY shows hi...A fluorescence-enhanced probe PY, which is based on integration of pyrene moiety and amino acid group,was developed for the orthogonal recognition of In3＋ and Al3＋ by the quick formation of 1：1 complex. PY shows high selectivity and sensitivity for In3＋ in NaOAc/HOAc（pH 4.8） buffer solution but rather for Al3＋ in methanol. Moreover, this probe shows good cell permeability, and the recognition of In3＋ by PY was successfully applied in bioimaging, which was the first example for detection of this metal ion in living cells.展开更多
基金Project supported by the Zhejiang Provincial Natural Science Foundation of China (LY24E020005)Industrial Key Projects of Jinhua City(2023-1-090)。
文摘Mixed-lanthanide(Ln) luminescent materials have important application values in ratiometric temperature sensing.Hydrogen-bonded organic frameworks(HOFs) offer a self-supporting network to conveniently tune multiple Ln^(3+)ions,but challenges still exist in material design.In this work,we selected two simple organic molecules as hydrogen-bonded building blocks,which are melamine(MA) and 2,5-pyridinedicarboxylic acid(PDC) owning the suitable energy to sensitize Tb^(3+)and Eu^(3+)ions.MA assists PDC molecules to support the network in a new HOF(MA-PDC),where the abundant carboxylic groups enable Ln^(3+)ions to combine with the HOF.Based on the effective energy transfer process,the emission of Tb^(3+)and Eu^(3+)from TbxEu1-x@MA-PDC(x=0.75,0.85,0.90) shows the obvious temperature dependence,which benefits ratiometric temperature detection.Taking Tb0.85Eu0.15@MA-PDC as an example,when temperature varies from 303 to 443 K,the intensity ratio exhibits distinct S-type response based on Mott-Seitz model.It also behaves good relative sensitivity(1.03%/K at 383 K),low temperature resolution(0.059 K) and large reproducibility(>96%).This work demonstrates that functionalization of a simple-component HOF with mixed Ln^(3+)ions is a fantastic strategy to develop novel ratiometric thermometers of both low cost and good performance.
文摘Sorption of lanthanum（Ⅲ）, cerium（Ⅲ and neodymium（Ⅲ） ions from the aqueous solutions of mixtures through adsorption on the biochar composites was investigated as a function of sorbent mass, pH, phase contact time and initial concentration of solutions at 295 K. The maximum removal of lanthanide ions takes place under the following conditions： 0.1 g of sorbent mass, pH 4 and 360 rain contact time for all studied initial concentrations of solutions. Kinetics of La（Ⅲ）, Ce（Ⅲ） and Nd（Ⅲ） ions sorption proceeded by a fast initial uptake reached equilibrium. This process was modelled by means of the pseudo first order, pseudo second order, intraparticle diffusion and Elovich models. The desorption of three lanthahide ions by nitric, hydrochloric and sulfuric acids at a concentration of 1 mol/L from biochar composites was also studied. In order to investigate the sorption mechanism FFIR, XRD and XPS analyses were performed after sorption of ions from the mixture.
基金financially supported by National Natural Science Foundation of China(No.11704081)Guangxi Natural Science Foundation(No.2017GXNSFBA198229)+2 种基金the Scientific Research Project for Higher Education of Guangxi Zhuang Autonomous Region(No.XBZ170336)the Doctoral Scientific Research Foundation of Guangxi University(No.BRP180253)The Improvement of Basic Ability for Youth Teachers in Guangxi Education Authority(No.2017KY0020)。
文摘The luminescence from lanthanide ions has potential applications in light emitting diodes,biomedical,solar cells,sensors,display,etc.However,the luminescence is suffered from the various problems,such as low luminescence efficiency and inharmonious wavelength for energy transfer.Magnetic field is an efficient method to modulate the wavelength and intensity of luminescence from lanthanide ions.Magnetic field redistributes the populated electrons in the excited states to tune the wavelength of lanthanide ions by Zeeman effect,mixing effect,and quantum confinement effect.Magnetic field enhances or suppresses the luminescence intensity by the administration of cross-relaxation,energy transfer,and Boltzmann population.In this review,we first introduce the various phenomena and mechanisms of magnetic field modulated downshift luminescence from lanthanide ions,including Zeeman effect,cross-relaxation,crystal structure,absorption,quantum confinement effect,and magneticoptical hysteresis.Then,we explain the regulation of upconversion luminescence by magnetic field,containing energy transfer and mixing effect.Finally,different options regarding how to understand the mechanism of magnetic field-modulated luminescence from lanthanide ions in the future are outlined.
文摘Ultrathin TiO_(2)nanosheets with coexposed{001}/{101}facets have attracted considerable attention because of their high photocatalytic activity.However,the charge-separated states in the TiO_(2)nanosheets must be extended to further enhance their photocatalytic activity for H_(2)evolution.Herein,we present a successful attempt to selectively dope lanthanide ions into the{101}facets of ultrathin TiO_(2)nanosheets with coexposed{001}/{101}facets through a facile one-step solvothermal method.The lanthanide doping slightly extended the light-harvesting region and markedly improved the charge-separated states of the TiO_(2)nanosheets as evidenced by UV-vis absorption and steady-state/transient photoluminescence spectra.Upon simulated sunlight irradiation,we observed a 4.2-fold enhancement in the photocatalytic H_(2)evolution activity of optimal Yb^(3+)-doped TiO_(2)nanosheets compared to that of their undoped counterparts.Furthermore,when Pt nanoparticles were used as cocatalysts to reduce the H_(2)overpotential in this system,the photocatalytic activity enhancement factor increased to 8.5.By combining these results with those of control experiments,we confirmed that the extended charge-separated states play the main role in the enhancement of the photocatalytic H_(2)evolution activity of lanthanide-doped TiO_(2)nanosheets with coexposed{001}/{101}facets.
基金Ph.D. Programme at the Department of Chemistry, University of Kerala, India
文摘A series of seven novel lanthanide（Ⅲ ） nitrato complexes with 4-[ N-（2-methoxybenzylimine）formyl] 1-2, 3- dimethyl-1-phenyl-3-pyazolin-5-one （2mbfa）, were synthesized. These complexes were characterized by elemental analysis, molecular mass determination, conductance and magnetic moment measurements, IR, UV-visible, and ^13CNMR spectral studies, In these complexes, the Schiff base, 2mbfa, acts as neutral bidentate ligand by utilizing the carbonyl oxygen and azomethine nitrogen as donor sites. All the three nitrate ions are also coordinated unidentately with 7 coordination for the lanthanide（Ⅲ） ions with a tentative monocapped octahedral geometry for the complexes. All the seven lanthanide（Ⅲ） complexes have a general formula, [ Ln（2mbfa）：（NO3）3 ].
基金supported by the National Natural Science Foundation of China(21077044)Natural Science Foundation of Shandong Province(ZR2015BM030)
文摘Extractability and extraction mechanism of lanthanide ions were investigated by using a new extractant,N,Nn,N′,N′-tetrabutyl-3-oxa-diglycolamide(TBDGA),in toluene from nitric acid media.The effects of HNO_3 and TBDGA concentrations,and temperature,on extraction of lanthanide ions were studied.Stoichiometrics of the main extracted species were HNO_3·TBDGA and M(NO_3)_3-3TBDGA(M = Er,Dy,Tb,Gd,La,Ce,Nd,Sm and Eu).The extracted species for metal ions were established to be ionic complex.In this complex,nitrate anion was not coordinated to the central ion.The extraction pattern increased gradually across the lanthanide ions series,showing enhanced affinity of TBDGA toward heavy lanthanide ions.Thermodynamic parameters were investigated for the exothermic extraction reaction.
基金Supported by the National Natural Science Foundation of China(No.20975009)
文摘Two new mononuclear lanthanide（Ⅲ） complexes Ln（pytz）3（H2O）3·（H2O）3.5[Ln=Tb（1）;Eu（2）;Hpytz=5-（2-pyridyl）tetrazole] were synthesized by reacting Hpytz with the corresponding lanthanide（Ⅲ） ions and characterized.The single crystal X-ray diffraction analysis reveals that complexes 1 and 2 are isostructural and the lanthanide（Ⅲ） ions in both complexes 1 and 2 are nine-coordinated,with three oxygen atoms of three coordination water molecules and six nitrogen atoms of three pytz ligands,forming a monocapped square antiprism.Extensive hydrogen bonds exist,resulting in a three-dimensional supramolecular network structure by hydrogen-bonds in both complexes 1 and 2,respectively.Complex 1 exhibits typical green fluorescence of Tb（Ⅲ） ion and complex 2 red fluorescence of Eu（Ⅲ） ion,in solid state at room temperature.
文摘A mixture containing eleven lanthanide ions was separated and detected on an anion exchange co lumn by ion chromatography with indirect photometry detection (IPC).An aqueous solution of 1.5×10 -2 mol/L nitrilotri(methylenephosphonic) acid and 2.5×10 -3 mol/L tiron was used as the eluent in which the former served as complexing agent and eluent,the latter played as color reagent and eluent.The effects of acidity,concentration and composition of eluent on the retention behavior of the analytes and detection sensitivity are discussed.
基金the National High-tech Research and Development Program of China(No.2002AA233051)the NationalNatural Science Foundation of China(No.20373019).
文摘Four kinds of lanthanide ions（Sm^3＋,Yb^3＋,Eu^3＋,La^3＋）as an additive were added into the aqueous solution containing methanol,respectively,and their effects on methanol elecotrooxidation in aqueous solutions were studied with cyclic voltammetry.The results show that the four kinds of ions have promotion action upon the electrooxidation of methanol to different degrees.The best additive,Sm^3＋,can increase the anodic oxidation current of methanol by 80%and the peak potential shifted negatively about 50 mV.The promotion effects of the lanthanide ions were considered to be related to the extranuclear electron distribution of these ions and their adsorption on the Pt electrode surface.
文摘The structure of phenylalanine transfer ribonucleic acid(tRNA Phe ) in solution was explored by 1 H NMR spectroscopy to evaluate the effect of lanthanide ion on the structural and conformational change. It was found that La 3+ ions possess specific effects on the imino proton region of the 1 H NMR spectra for yeast tRNA Phe . The dependence of the imino proton spectra of yeast tRNA Phe as a function of La 3+ concentration was examined, and the results suggest that the tertiary base pair G 15 ·C 48 , which is located in the terminal in the augmented dihydrouridine helix(D helix), was markedly affected by La 3+ (shifted to downfield by as much as 0 35). Base pair U 8·A 14 in yeast tRNA Phe , which are stacked on G 15 ·C 48 , was also affected by added La 3+ when 1～2 Mg 2+ were also present. Another imino proton that may be affected by La 3+ in yeast tRNA Phe is that of the tertiary base pair G 19 ·C 56 . The assignment of this resonance in yeast tRNA Phe is tentative since it is located in the region of highly overlapping resonances beween 12 6 and 12 2. This base pair helps to anchor the D loop to the TΨC loop. The binding of La 3+ caused conformational change of tRNA, which is responsible for shifts to upfield or downfield in 1 H NMR spectra.
文摘Two isomorphous 2D zigzag-ladder structure coordination polymers containing coordination supramolecular capsules are reported,which are built by trivalent lanthanide ions,pyridine N-oxide（PNO） and p-sulfonatothiacalix[4]arene（H4TCAS4-）：[Ln2（PNO）2（H2O）10？（H2TCAS）2].[Ln2（H2TCAS）2（H2O）6（MeOH）2].2MeOH.12H2O（Ln = La,1;Nd,2）.Crystal data for complex 1：C31H51La2NO33S8,Mr = 1500.03,triclinic system,P 1 space group,with a = 11.732（2）,b = 15.007（3）,c = 15.262（3）,α = 78.05（3）,β = 80.77（3）,γ = 83.89（3）°,Z = 2,V = 2587.3（9）3,Dc = 1.925 g/cm3,μ = 2.051 mm-1,F（000） = 1500,the final R = 0.0300 and wR = 0.0823;and those for complex 2：C31H51Nd2NO33S8,Mr = 1510.69,triclinic system,P1 space group,with a = 11.719（2）,b = 14.941（3）,c = 15.157（3）,α = 78.03（3）,β = 80.84（3）,γ = 83.95（3）°,Z = 2,V = 2555.9（9）3,Dc = 1.963 g/cm3,μ = 2.436 mm-1,F（000） = 1512,the final R = 0.0493 and wR = 0.1267.There are two coordination environments of lanthanide ions.One is bridged by two PNO molecules forming a dimeric Ln ion in the O,O’-μ2 mode.The dinuclear ions are shrouded by two H2TCAS6-ions through coordination interactions and hydrogen bonds.The other coordination mode of Ln ions is a zigzag 1D chain linked by up-down H2TCAS6-ions.By the coordination capsules,the complexes form 2D zigzag-ladder structure coordination polymers.
基金Project supported by the National Natural Science Foundation of China(U21A2068,11974142,11874181,12204248)the Fundamental Research Funds for the Central UniversitiesJiangsu Funding Program for Excellent Postdoctoral Talent(2022ZB399)。
文摘The toxicity of lead ions has become the severe challenge for the all-inorganic lead halide p erovskite materials,although some works have rep orted the lead-free perovskite nanocrystals(NCs),the photoluminescence quantum yield(PLQY)of these materials is still unsatisfactory.Meanwhile,because the halogen ions can be easily exchanged,the controllable multicolor emission in perovskite NCs is difficult to realize in current reports.In this work,we introduced lanthanide ions into lead-free Cs_(3)Sb_(2)Cl_(9) perovskite NCs.Benefitting from the energy transfer between Cs_(3)Sb_(2)Cl_(9) perovskite NC host and lanthanide ions,the multicolor emission was realized.Based on controlling the doping concentration of Tb^(3+)and Eu^(3+)ions,the white light emission under UV excitation would be turned easily in the Tb^(3+)/Eu^(3+)codoped NCs.In addition,efficient energy transfer from perovskite NCs to Tb^(3+)or Eu^(3+)ions is beneficial to improving the optical properties of lead-free perovskite NCs,resulting in maximum PLQYs of red,green and white light emission of 22.6%,19.7%and 28.5%,respectively.Finally,a white light emitting device(WLED)was fabricated with a power efficiency of 18.5 lm/W,which presents the Commission Internationale de l'Eclairage(CIE)of(0.33,0.35).
基金Project supported by the National Key Basic Research Program of China(2013CB921800)the National Natural Science Foundation of China(11274299,11374291,11574298,11204292,11404321)the Anhui Provincial Natural Science Foundation(1308085QE75)
文摘Based on the completely parametric crystal-field model, the energy level parameters, including free-ion parameters and crystal-field parameters, obtained by fitting the experimental energy level data sets of Ln^（3＋） in LiYF_4 were systematically analyzed. The results revealed that the regular variation trends of the major parameters at relatively low site symmetry still existed. The g factors of ground states were calculated using the parameters obtained from least-squares fitting. The results for Ce^（3＋）, Nd^（3＋）, Sm^（3＋）, Dy^（3＋） and Yb^（3＋） were in good agreement with experiment, while those of Er^（3＋） deviated from experiment dramatically. Further study showed that the g factors depended strongly on B_4~6, and a slightly different B_4~6 value of -580cm^（-1） led to g factors agreeing well with the experimental values.
文摘The molecular interactions between Nd^(3+), Gd^(3+)and Yb^(3+) and DPPC in multibilayer have been studied by Fourier transform infrared spectroscopy. The results show that incorporations of the lanthanide ions considerably shift the gel to liquid-crystal phase transition to higher temperatures. The incorporations of Gd^(3+) and Yb^(3+) obviously reduce the cooperations of the transition. The phosphate region of the spectra indicates that the Ln^(3+) binding to DPPC forms DPPC-Ln^(3+)complex and the Lna^(3+)binding is not dependent on the phase state of DPPC. The C-H stretching region of the spectra suggests that the incorporation of Ln^(3+)increases the conformational order of DPPC both in gel and in liquid-crystal phase as a result of the reduction of gauche rotamers.
基金Project(51474254)supported by the National Natural Science Foundation of ChinaProject(2013M531813)supported by the China Postdoctoral Science Foundation+1 种基金Project(2016zzts111)supported by the Independent Exploration and Innovation Program of Central South University,ChinaProject(CSUZC201715)supported by Open-End Fund for the Valuable and Precision Instruments of Central South University,China
文摘The adsorption behavior and mechanism of Bi（Ⅲ） ions on the rutile-water interface were investigated through micro-flotation, Zeta potential measurement, adsorption amount measurement and X-ray photoelectron spectroscopy（XPS）. According to the results of micro-flotation, Bi（Ⅲ） ions could largely improve the rutile flotation recovery（from 62% to 91%）, and they could increase the activating sites and reduce the competitive adsorption between nonyl hydroxamic acid negative ions and OH-ions, which determined that Bi（Ⅲ） ions were capable of activating rutile flotation. The adsorption of Bi（Ⅲ） ions onto the rutile surface led to the shift of Zeta potential into the positive direction, which was good for the adsorption of nonyl hydroxamic acid anions. In addition, the results of XPS indicated that the chemical environment around Ti atom had not changed before and after the adsorption of Bi（Ⅲ） ions. Based on the adsorption mechanism of Bi（Ⅲ） ions, it was deduced that firstly Bi（Ⅲ） ions occupied the vacancies of the original Ca^2＋, Mg^2＋ and Fe^2＋ ions on the rutile surface; secondly Bi（Ⅲ） ions covered on the rutile surface in the form of hydroxides.
基金supported by the National Natural Science Foundation of China (51962008)。
文摘The exploitation of a highly selective and sensitive probe to detect both cancer marker and metal ion is of great importance.In this work,the "one stone two bird" agent of 1,10-phenanthroline(phen) is designed to disrupt the polymeric lanthanide MOFs(LnMOFs,[Ln(CHO_(2))_(3)]n,Ln=Tb,la;Eu,1 b,CHO_(2)=formic acid) {[Ln(CHO_(2))_(4)·(C_(2) H_(8) N)]n,Ln=Y,2 a;Gd,2 b;Dy,2 c,C_(2)H_(8) N=dimethylamine}) into a soluble mononuclear species [Ln(phen)_(2)(NO_(3))_(3),Ln=Tb,3 a;Eu,3 b] as well as to provide an antenna for efficient photons absorption,resulting in an ultra-high luminescence quantum yield(QY,90%) europium complex.The luminescence QY is among the highest record of monomeric(zero-dimensional) lanthanide complexes.Furthermore,mononuclear Tb3+complex(3 a) functions as a multiplex sensor towards both Fe^(2+)and cancer marker of 5-hydroxyindole-3-acetic acid(5-HIAA).Importantly,the limit of detection(LOD)for sensing 5-HIAA is an ultra-sensitive value of 1 × 10 s mol/L,which is even lower than that necessary for the early diagnosis of carcinoid tumors.More interestingly,sensing results in simulated urine reveals that 3 a has potential application for early diagnosis in the clinic.
基金Supported by the National Natural Science Foundation of China(No.21576112)Natural Science Foundation Project of Jilin Province(No.20130521019JH and 20150623024TC-19)+1 种基金Natural Science Foundation Project of the Education Department of Jilin Province(No.[2014]152)the Science and Technology Development Plan of Siping City(2015049)
文摘Three lanthanide（III） complexes [Ln（4-NCP）（1,4-BDC）]n·xn H2O（Ln = Pr（1）, Sm（2）, Nd（3）. 4-HNCP = 2-（4-carboxyphenyl）imidazo（4,5-f）（1,10）phenanthroline, 1,4-H2 BDC = benzene-1,4-dicarboxylic acid） have been hydrothermally synthesized and characterized via elemental analysis, infrared spectrometry and single-crystal X-ray diffraction. Structural analyses revealed that complexes 1~3 possess similar porous three-dimensional frameworks with the point symbol {4^（12）·6~3}. Meanwhile, complexes 1~3 exhibit excellent thermal stabilities and complex 2 exhibits characteristic luminescent property.
基金financially supported by the National Natural Science Foundation of China(Nos.51004072,51004033,51074047)the National“Twelfth Five-Year”Plan for Science&Technology Support Program of China(No.2012BAE01B02)。
文摘Xanthated crosslinked chitosan(XCCS) resin prepared under microwave irradiation were used for adsorbing Au(Ⅲ) ions in hydrochloric acid medium.The influence of pH and temperature on the adsorption capacity of XCCS was investigated.The original XCCS and the loaded XCCS were characterized by scanning electron microscope(SEM) and X-ray diffraction(XRD),respectively.The results indicate that the XCCS has ability to adsorb Au(Ⅲ) ions and the maximum adsorption capacity of Au(Ⅲ) ions on XCCS is observed at pH 1 and 20℃.The data of batch adsorption tests are fitted to kinetic models and isotherm models,respectively.The kinetics of adsorption process is found to follow pseudo-second-order kinetic rate model,and equilibrium data agree very well with the Langmuir model.Thermodynamic calculation of the Au(Ⅲ) ions adsorption process indicates that the adsorption process is spontaneous and endothermic.
基金supported by the National Natural Science Foundation of China (Nos. 21572091 and 21472075)the Fundamental Research Funds for the Central Universities (No. lzujbky-2016-51) by MoE of China
文摘A fluorescence-enhanced probe PY, which is based on integration of pyrene moiety and amino acid group,was developed for the orthogonal recognition of In3＋ and Al3＋ by the quick formation of 1：1 complex. PY shows high selectivity and sensitivity for In3＋ in NaOAc/HOAc（pH 4.8） buffer solution but rather for Al3＋ in methanol. Moreover, this probe shows good cell permeability, and the recognition of In3＋ by PY was successfully applied in bioimaging, which was the first example for detection of this metal ion in living cells.
