Nano ZnO for functional applications
Preparation of nano ZnO for high energy field varistors was carried out. Studies were also initiated to fabricate ZnO coatings and dispersions for functional materials. Three attempts namely (i) preparation of ZnO-biopolymer nanocomposites for functional textiles and polymer foams (ii) ZnO-flyash composites for luminescent glaze layers and (iii) vertical/aligned growth of ZnO nanostructures on seeded substrates have been attempted. Stable ZnO NPs of size <50 nm was achieved by in situ nucleation and growth in the starch, gelatine, chitosan and agar media through sonochemical technique and the ZnO-biopolymer functional surface was made on cotton fabrics and poly urethane foams. The foams and cottons sprayed with ZnO-biopolymers strongly resist the growth of fungus under accelerated conditions. The incorporation of Co doped ZnO in 70 wt% Flyash+10 wt% Al2O3 glaze compositions exhibit green luminescence under incandescent light. Highly aligned growth of ZnO nanostructures were fabricated on ZnO seeded glass, metals and mica surfaces. Network like ZnO growth having nano porosities has been achieved on Al-substrates by in situ hydrolysis of HMTA+Zn precursors.
Materials Science and Technology