Gaining thermochromic property of quartz lamel surface and functionalization

Abstract

The aim of this study was to obtain functional features by coating the quartz lamella with a sol-gel technique. Smart functional material was developed by including microencapsulated thermochromic pigments in coatings. Using anatase powder titanium (IV) oxide with additions in different ratios, the coatings were applied to the quartz lamel surfaces by dip-coating technique. The sol formulation was made using the initial precursors Tetraethoxysilane (TEOS) and 3-aminopropyltriethoxysilane (APTES). Tetraethoxysilane was added to the structure of the coatings to increase the adhesion of the coatings to the substrate. Thermochromic coatings were synthesized by reacting polyvinylpyrrolidone in aqueous solution with tetraethoxysilane. The structural and thermochromic performance of coatings prepared with the sol-gel dip-coating method was systematically characterized and its functionality was determined. In this study, the effects of the addition of titanium (IV) oxide on the phase composition, transition temperature, and surface morphology of the coatings were investigated. The result obtained showed that the formed anatase phase increased as the titanium (IV) oxide content increased. Exothermic and endothermic transition temperatures for the undoped sample ranged from 34.6 °C to 26.5 °C, while 3 g titanium (IV) oxide doped sample these temperatures varied from 34.6 °C to 26.7 °C. Smooth surface coatings were prepared using polyethylene glycol. The results demonstrated that the colors of the obtained thermochromic coatings could be reversibly changed between green and white.