ZrO2-doped ZnO-PDMS nanocomposites as protective coatings for the stone materials

Abstract

<p class="Abstract"><span lang="EN-US">ZnO is a semiconductor that has found wide application in the optics and electronics areas. Moreover, it is widely used in different technological areas </span><span lang="EN-US">due to its beneficial qualities (high chemical stability, non-toxicity, high photo-reactivity, and cheapness). Based on its antibacterial activity, recently it has found also application to prevent bio-deterioration of cultural heritage buildings. As many authors suggested, doped ZnO nano-structures exhibit better antibacterial properties than undoped analogues. In the present work, ZnO nanoparticles doped with ZrO<sub>2</sub> have been prepared by a sol-gel method in order to enhance the photocatalytic properties as well as the antibacterial activity of ZnO. Then, ZrO<sub>2</sub>-ZnO-PDMS nanocomposite (PDMS, polydimethylsiloxane used as the binder) was synthesized by in-situ reaction. The resulting nanocomposite has been investigated as a possible protective material for cultural heritage building substrates. The performances of newly prepared coating were evaluated in three different stones (Lecce stone, Carrara Marble and Brick) and compared with Plain PDMS as a reference coating. </span></p>