Ultralong silica nanotubes assembling macroscopic non-woven mat from bacterial cellulose template

Ultralong SiO2 nanotubes (SNTs) assembling non-woven mat are successfully synthesised by a sol-gel nanocoating technique. The formation of SNTs by a templating mechanism is accomplished in a bacterial cellulose (BC)/tetraethoxysilane (TEOS) system. The mineralisation process of TEOS on the surface of BC is measured by SEM and TEM. The hydroxyl groups of BC directly provide nucleation sites of silica mineralisation and catalyse silica polymerisation at their surface. The average diameter of SNTs and the wall thickness are 100 and 15 nm respectively. Compared with SiO2 nanoparticles, the photoluminescence of SNTs showed an obvious blue shift.