Application of Mesoporous Silica Aerogel Prepared with Ionic Liquid Template1.PAN/A-SiO2 CPEs for High Capacity Lithium Battery2.High Efficiency Sunscreen Encapsulated Silica

• Main Authors: Yi-Ting Chen, 陳羿廷
• Other Authors: Yui Whei Chen-Yang
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/ny5cn9

博士 === 中原大學 === 化學研究所 === 99 === Abstract 1. PAN/A-SiO2 CPEs for High Capacity Lithium Battery The objective of this study is to investigate the effect of morphology of SiO2 filler on the PAN-based composite polymer electrolytes (CPE). Hence, a series of composite polymer electrolytes based on PAN were prepared and the effect of addition of the SiO2 fillers, including the mesoporous silica aerogel (A-SiO2)、mesoporous MCM-41 silica (M-SiO2) and a nonporous commercial silica (D-SiO2), on the composite polymer electrolytes was discussed. The best conductivities obtained at room temperature is 6.0×10-4 S/cm, 4.5×10-4 S/cm and 2.3×10-4 S/cm for the CPE with 3wt% A-SiO2, 3wt% M-SiO2 and 4wt% D-SiO2, respectively. The interactions among the components of the electrolytes were also analyzed by the results of FT-IR and solid state Li NMR spectra. Furthermore, the electrochemical stability of the composite polymer electrolytes was studied by linear sweep voltammetry and cyclic voltammetry analyses. The above results revealed that the as-prepared polymer electrolytes prepared have good electrochemical stability, high oxidation breakdown voltage (4.5V vs. Li/Li+) and good compatibility with the lithium metal electrode. The capacity of the cell fabricated with the composite polymer electrolyte based on PAN/LiClO4/A-SiO2 measured with 0.5C of charge-discharge rate is 121mAh/g. It was also found that after twenty times charges-discharges, the capacity of the cell still remained 100%. The result indicates that the composite electrolyte prepared is a potential candidate as a solid electrolyte for secondary lithium battery. 2. High Efficiency Sunscreen Encapsulated Silica In this study the sun-screening material, octyl methoxycinnamate (MCX) or Octyl salicylate (EHS), was encapsulated by a mesoporous silica aerogel to enhance the screening effect and stability to prevent skin damages caused by ultraviolet. The encapsulated SiO2-MCX was prepared by in-situ sol-gel polymerization of tetraethyl orthosilicate (TEOS) and MCX with an ionic liquid as the template as well as the solvent. The as-prepared SiO2-MCX was characterized by Brunauer–Emmett–Teller (BET), Fourier transformation infrared (FT-IR), thermo¬gravimetric analysis (TGA), s solid state 29Si NMR, UV-Visible Spectrophotometer, and SPF-290S analyzer. The results indicated that the SiO2-MCX and SiO2-EHS particles are mesoporous material with high surface area and pore volume and about 60wt％ of MCX and 55wt % of EHS was encapsulated in the mesopores of the SiO2 framework, respectivley. It was also found that the UV absorption value of the as-prepared SiO2-MCX and SPF of the as-prepared SiO2-MCX containing sun-screening lotion were much higher than that of the corresponding pure MCX material and lotion.