Preparation of zirconia aerogel with L-glutamic acid

Abstract

In preparation of zirconia aerogel, propylene oxide (PO) is generally used as gel accelerator. PO is toxic and harmful to the environment. So in this article, green, environmental protection, safe and non-toxic L-glutamic acid (LGA) and L-aspartic acid (LAA) have been applied as gelators to replace PO. Series of ZrO₂ aerogels have been synthesized with sol-gel method by ethanol supercritical drying and characterized by XRD, SEM and TEM techniques. Nitrogen adsorption-desorption measurements have been used to characterize the specific surface area. The effect of H⁺ concentration on the crystallinity of zirconia has also been studied. The prepared ZrO₂ aerogels with low density, low thermal conductivity, and high specific area can make them promising candidates for a wide array of multifunctional applications, e.g., catalyst support, energy conversion, and thermal insulation.