Preparation of Ta₂O₅ aerogel with metal alkoxide method

With metal alkoxide as precursor, Ta2O5 aerogels were prepared by sol-gel technique. The sol-gel process is found to be affected by water amount, catalyst amount and concentration of Ta(OC2H5)5. The gelation can only happen in the presence of strong acid as catalyst, and with the increase of acid strength, the gelation time is obviously decreased. With the continuous increase of water, the gelation time lengthens and then tends to be constant. Additionally, the gelation time increases and the theoretical density of Ta2O5aerogel decreases as the solvent amount increases. Through sol-gel process control along with supercritical drying technique, the Ta2O5 aerogel with a low density of 44 mg/cm3 was prepared.