Lightweight glass/carbon composite hollow microspheres with intact shell and good thermal stability

This work proposed a facile strategy to prepare glass/carbon composite hollow microspheres with intact shell and good thermal stability by in-situ depositing resorcinol-formaldehyde (RF) on hollow glass microspheres (HGS) and subsequently heat-treated at 800 °C. The structure formation of glass/RF composite hollow spheres were investigated and the results indicated that growth of RF colloid nanospheres on HGS was promoted by assistance of cetyltrimethylammonium bromide (CTAB). RF transformed into carbon via thermal pyrolysis to release CO₂, H₂O and CH₄ at inert atmosphere. Meanwhile, RF protected HGS from structure thermal deformation and the thermal stability of HGS was enhanced. Thus, shell structure of formed glass/carbon composite hollow microspheres was intact. This method avoided the traditional procedure to prepare template in prior and subsequently remove it. The obtained glass/carbon composite hollow microspheres with lightweight property and thermal stability would be potentially used as thermal insulator in the fields of thermal protection.