Superior Performance of Dye-Sensitized versus Conventional TiO2 Nanoparticles for Promoting Germination and early Growth of Barley: From Photovoltaic to Biotechnological Application

Abstract

TiO2 nanoparticle is one of the most fascinating materials for stimulating germination and growth of various seeds. However, the low capacity of these materials in absorbing sunlight is a challenging issue which should be taken into consideration. Sensitization of TiO2 nanoparticles is already a common strategy for improving its visible light absorption and it is mainly used in dye-sensitized solar cells. In this study, a set of experiments were conducted to investigate the influences of dye-sensitized TiO2 nanoparticles on germination and growth of barley seeds (Hordeum vulgare L.). Fluorescein was used as the sensitizer with high extinction coefficient in the visible regions. It was shown that different growth parameters including seedling fresh and dry weights, root and shoot lengths, chlorophyll-a, and chlorophyll-b were increased by 59.2% and 85.7%, 330%, 100%, 45% and 50% relative to the control, respectively. Moreover, the results confirmed that dye-sensitized TiO2 nanoparticles do not have any negative influence on germination parameters and are beneficial for increasing vigor index I.