Enhancing thermal stability and electrical conductivity performance of silica aerogel via graphene oxide integration

Silica aerogels, known for their low densities and large surface areas, have faced limitations such as low thermal stability, mechanical strength, and high electrical resistivity, hindering their widespread applications. In this study, graphene oxide (GO) was incorporated into a silica aerogel matrix to enhance its thermal stability and electrical conductivity. The GO content ranged from 5% to 15% (wt). The synthesis involved preparing silica aerogel matrices with varying concentrations of GO, and the effect of GO on properties such as density, porosity, thermal and chemical stability, conductivity, and aerogel morphology was thoroughly investigated. Analysis revealed that GO addition enhanced several key properties where thermal stability increased from 553 °C to 585 °C, electrical conductivity improved significantly by approximately four orders of magnitude with 15% GO (from 3.22 × 10⁻¹²S/cm to 4.23 × 10⁻⁸S/cm), and hydrophobicity was enhanced with increasing GO content due to altered surface chemistry. The optical band gap decreased from 3.97 eV to 3.05 eV with 15% GO, indicating improved light absorption properties. Surface studies indicated changes in pore size distribution and surface area, with specific surface area decreasing from 761 m²/g to 369 m²/g with 15% GO due to densification of the aerogel structure. Morphological analysis via SEM showed directional growth of GO nanosheets within the aerogel matrix. These findings underscore the pivotal role of GO in achieving nanocomposites with superior properties, offering promising prospects for applications requiring lightweight materials with enhanced thermal and electrical characteristics.