Low-Cost Synthesis of Silicon Quantum Dots and Their Applications on Luminescent Solar Concentrators

Here, we developed a cost-effective batch synthesis method for silicon quantum dots (Si QDs) with large Stokes shift and high quantum yield (>50% in polymer nanocomposite) for efficient light conversion. These Si QDs were fabricated from an inexpensive commercial precursor (triethoxysilane, TES), using optimized annealing and etching processes. The optical properties of such QDs are similar to those prepared from state-of-the-art precursors (hydrogen silsesquioxane, HSQ) yet featuring an order of magnitude lower cost. FTIR revealed that the surface oxide on Si QD was closely related to its light conversion efficiency. Based on this mass production method, we are able to investigate many factors when applying Si QDs as fluorophores in luminescent solar concentrators (LSCs), such as the thickness of polymer interlayer, the appropriate UV dose for curing polymer to avoid haze etc. Eventually, we are aiming at transparent large-area light-harvesting devices serving as "solar windows".