| The rare-earth metal coordination polymers have a variety of applications in gas storage and separation,white-light emitting material,molecular sensing,image,catalysis due to their unique fluorescent or magnetic properties.Moreover,these complexs own high structure regularity.So many researchers maintain the original framework topologies via a doping approach to gain multi-metals or multi-ligands complexes with novel luminescence and magnetic properties in recent years.Compared to mono-metal complex,doping coordination polymers have more remarkable advantages,for example:more sensitive,high-speed and so on.In this paper,we developed a series of isostructural polymers with dual-metals(two rare earth metals or 3d-4f heterometal)or dual-ligands via a doping approach.Moreover,we systemically studied the luminescence properties.The detailed work are summarized as follows:(1)we synthesized a battery of isostructural complexes on the basis of la,2a,3a,4a and 5a by solvothermal method.[Tb2(DHBDC)3(DMF)4]n·2nDMF Complex la[Eu2(DHBDC)3(DMF)4]n·2nDMF Complex 1b[Tb2xEu2(i-x)(DHBDC)3(DMF)4]n·2nDMF Complex lc?Id?le?if?(x=0.9?0.8?0.7?0.6.0.5?0.4?0.3?0.2?0.1)1g?1h?1j?1k?lm[Tb2xEu2(1-x)(DHBDC)3(DMF)4]n 2nDMF x=0.695 Complex In[Tb2(N-BDC)3(DMF)4]·n2nDMF Complex 2a[Eu2(N-BDC)3(DMF)4]·n 2nDMF Complex 2b[Tb2xEu2(1-x)(N-BDC)3(DMF)4]n·2nDMF Complex 2c?2d?2e?2f?(x=0.1?0.3?0.5?0.7?0.9?0.99?0.997?0.999)2g?2h?2j?2k[ZnSm(PDA)2(N-BDC)1/2(H2O)]n·2nH20 Complex 3a[ZnEu(PDA)2(N-BDC)1/2(H2O)]n·2nH20 Complex 3b[ZnTb(PDA)2(N-BDC)1/2(H2O)]n·2nH20 Complex 3c[ZnNd(PDA)2(N-BDC)1/2(H2O)]n·2nH20 Complex 3d[ZnGd(PDA)2(N-BDC)1/2(H2O)]n·2nH2O Complex 3e[Tb2Mn(FD A)4(glycol)2]n·2nH20 Complex 4a[Nd(Suc)1/2(BPDC)]n Complex 5a[Tb(Suc)1/2(BPDC)]n Complex 5b[Eu(Suc)1/2(BPDC)]n Complex 5c(2)All polymers were further characterized by X-ray single crystal diffractive technology,X-ray powder diffraction,IR,fluorescent spectra,UV-Vis diffuse reflection,TG analysis.Compounds(la,2a,3a,4a and 5a)possess 3D structure.In these complexes,la,2a and 4a exhibit ID quadrangle channels while 3a and 5a have no obvious channel owing to interpenetrated network and distortion.All complexes in the same series are isostructural by X-ray powder diffraction.(3)We investigated the white-light properties of complex In.In the experiment,we chose benzene-2,5-dihydroxy-1,4-dicarboxylic acid as organic-ligand and adjusted the molar ratio of Tb/Eu to obtain white-light,and the standard CIE is(0.34,0.31).(4)We explorated the temperature-dependent photoluminescent(PL)properties of 2k under the 77 K-300 K.As the temperature increases,the temperature dependent luminescence colors of 2k are systematically tuned from the green to red,which can be clearly and directly observed even by the naked eye.The fact that the temperature can be linearly related to IEu(6 14 nm)/ITb(546 nm)from 77 to 207 K.With the temperature increasing,the fluorescence intensity and fluorescence lifetime of Tb(SD4?7F5)decreases,while Eu(5D0?F2)shows opposite change,indicates that 2k is an excellent luminescent thermometer at this temperature range.(5)We investigated the molecular sensing of 1j,2k,3b.The selectivity and sensitivity of the fluorescence response of 1j to acetic acid and Fe3+ show that it could be used as efficient fluorescence sensors for acetic acid and Fe3+.Meanwhile,complex 2k and 3b possess potential applications in detecting Cr3+.Polymer 2k recognizes Cr3+ by fluorescence quenching while compound 3b makes use of the offset of ligand s fluorescence position. |
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