Synthesis And Properties Of PEO Composite Solid Electrolyte

Lithium battery is one of the most widely used energy storage battery in the world.Compared with the traditional liquid electrolyte,solid electrolyte has the advantages such as high boiling point,low toxicity and high safety.Currently,the development of solid electrolyte with high stability and high ionic conductivity is one of the hotspots and difficulties in the field of lithium battery.In this paper,PEO composite solid electrolyte have been synthesized by combining different kinds of fillers（including 3D-LLZAO and MIL-101-SO₃Li）in the presence of ionic liquid.Additionally,the structure and electrochemical properties of the electrolytes have been characterized systematically.On the other hand,the sensing ability of several luminescent MOFs towards antibiotics have been investigated.The research of this paper mainly includes the following three parts:1.Preparation and characterization of composite polymer electrolytes IL@3D-LLZAO@PEO.A three-dimensional porous ceramic LLZAO has been synthesized and proposed as a scaffold,into which Li Cl O₄,PEO and Li（G4）TFSI can be infiltrated to make IL@3D-LLZAO@PEO composite electrode membranes.The structure and surface topography of the membranes have been characterized by IR,XRD,TG,SEM,et al.Additionally,electrochemical analyses show that the ionic conductivity of IL@3D-LLZAO@PEO at 20°C is has high as 1.05×10^-4 S cm^-1,which is better than that without G4 or with micrometer-sized LLZO particles as fillers.Generally,the excellent performance of the composite electrolyte might be due to the following two points:I.3D LLZAO can provide continuous and fast Li⁺ion transport channels;II.the interface resistance can be reduced by the addition of ionic liquid Li（G4）TFSI.2.Preparation and characterization of composite polymer electrolytes IL@MIL-101-SO₃Li@PEO.A single lithium-ion conductor IL-MIL-101（Cr）-SO₃Li has been prepared by post-synthesis modification and characterized by XRD,IR,SEM,et al.Then,IL@MIL-101（Cr）-SO₃Li@PEO composite electrolyte membranes have been fabricated with different proportions of IL-MIL-101（Cr）-SO₃Li as fillers.Electrochemical analyses show that the ionic conductivity of IL@MIL-SPE is 9.01×10^-6,which is higher than that without IL as the fillers.It is proposed that EMIM⁺and TFSI^-are encapsulated in the porosity of MIL owing to their larger radius,while smaller Li⁺can transport freely.3.Luminescence sensing properties of several luminescent MOFs towards NFs antibiotics.Three kinds of luminescent CPs（Zn-1,Zn-2,Cd-1）were used as fluorescent probes for detection of trace amounts of nitrofurantoin（NFT）and nitrofurazone（NFZ）antibiotics via luminescence quenching,with high Ksv values and low LOD.Moreover,the possible mechanism for the luminescence quenching has been investigated.