Visible luminescence from triethanolamine-modified zinc oxide nanoparticles

We report sol-gel synthesis of ZnO NPs in support of Triethanolamine (TEA) molecules. The particle sizes lie in the range of 23 nm - 43 nm. The blue-shift in absorption spectra for all powders is attributed to the quantum confinement effect. ZnO nanopowder annealed at higher temperature shows an enhanced visible luminescence. In comparison, ZnO specimens having large grain size which are prepared without using TEA do not show any emission with significant intensity. An energy band diagram of nanostructured ZnO specimens explains the luminescence results.