Spectral Regulation And White Light Properties Of Rare Earth-Free MOFs Materials Based On Host-Guest System

The development and application of white light emitting diode（WLED）lighting technology is of great significance for reducing energy consumption.At present,commercial WLED phosphors mostly rely on rare earth elements.However,rare earth elements are non-renewable strategic resources,and the process of mining and refining them has adverse effects on the environment.In recent years,the development of new white luminescent materials without rare earth elements has attracted wide attention of researchers.Metal-organic frames（MOF）are ideal for white light emitting materials due to their high surface area,adjustable pore structure and abundant luminescence sites.This paper starts from the synthesis of MOF and uses MOF as the main body to encapsulate various luminescent objects.A series of rare earth-free MOF luminescent materials based on host and guest system are prepared,and their applications in WLED are studied.1.A novel 3D anionic In-MOF was synthesized by self-assembly of organic ligand（5,5’-（anthracene-9,10-diyl）isophthalic acid（H₄L））and metal indium ions.The In-MOF has high porosity,high stability and strong blue light emission.By soaking and in-situ methods A series of dyes@In-MOF single-phase phosphor materials were successfully prepared by encapsulating fluorescent dyes in In-MOF.The test shows that the dye@In-MOF prepared by in-situ adsorption method can effectively increase the dye loading and fluorescence quantum yield,and the dye leakage phenomenon has also been greatly improved.In situ（RhB/AF@In-MOF）-3（RhB:Rhodamine B;AF:acridine flavin）fluorescence quantum yield up to 42.27%.The luminous efficiency（LE）of WLED device is 50.75 lm/W,the Ra value is 91.2,and the CIE coordinates are（0.33,0.31）,which is close to the CIE coordinates of standard white light（0.33,0.33）.The above results show that the phosphor materials prepared by in-situ method have good fluorescence and LED performance,and have the possibility of application in smart white LEDs.2.The F@ZIF-8 composite with high fluorescence quantum yield was successfully prepared by high concentration reaction（HCR）,and then the red emitter RhB was introduced by coating growth to obtain the yellow light material F@ZIF-8@RhB@ZIF-8 with high luminescent properties.The CCT and CIE of WLED devices are 5982 K and（0.32,0.32）respectively,and the luminous efficiency is as high as 95.16 lm/W.F@ZIF-8@RhB@ZIF-8/BN is finally obtained by adding BN with good heat dissipation and small light absorption.The material still has a high QY,and the CCT,CIE and LE of LED devices are 6253 K,（0.31,0.34）and 92.83 lm/W,respectively.Which is very close to the LED performance of F@ZIF-8@RhB@ZIF-8.Compared with the raw materials,the blue light stability of the emission peaks of sample F@ZIF-8@RhB@ZIF-8/BN at F and RhB and the heat dissipation performance of LED are improved by 35%and 31%,20%and 21%,respectively.3.The stability of pure inorganic perovskite material limits its development in WLED field.Perovskite@ZJU-28 material with high performance and green luminescence was obtained by introducing perovskite into anionic frame ZJU-28 by simple mechanical grinding method.The fluorescence quantum yield of this material was as high as 46.92%,and the luminous intensity only decreased by 10%after being exposed to air for a period of time,which was greatly improved compared with pure perovskite.Perovskite@ZJU-28 is mixed with commercial red phosphor to obtain white light emission.The LE,Ra,CCT and CIE of the device are 25.82lm/W,57,7015 K and（0.30,0.35）respectively.And the WLED can reach 127%NTSC.The quantum yield of yellow light material Perovskite@RhB@ZJU-28 prepared by grinding method is 23.5%.Driven by 10 m A current,the LE,CCT,CIE and R₉ of the LED device are4718 K,（0.33,0.26）and 75.9,respectively.WLED can cover 121%NTSC.Experiments show that this simple and efficient solvent-free grinding method is a feasible way to prepare high-performance and stable Perovskite composites and use them in WLED.