Luminescent solar concentration of type-II nanoplatelets

Abstract

The growing demand for renewable energy sources, driven by economic and environmental considerations, has spurred the development of more efficient methods for harnessing solar power. Luminescent solar concentrators (LSCs) are emerging as a promising technology platform owing to their capability to collect and concentrate sunlight delivered to the mounted photovoltaic cells where electrical power is generated. Nanoplatelets (NPLs) draw significant attention as luminophores for LSCs because of our ability to easily alter their optoelectronic properties via tailoring their size, shape, and composition, while making use of advanced architectures of their heterostructures. In this thesis, controlling their composition carefully, CdSe/CdSe1-xTex/CdSe/CdS NPLs in the core/multicrown architecture with type-II band alignment benefitting from their type-II heterostructure’s lower emission energies in the solar spectrum and the suppression of their reabsorption losses were synthesized as the LSC luminophores. The physical characteristics and morphology of these hetero-NPLs were systematically investigated with structural analyses. The resulting CdSe/CdSe1-xTex/CdSe/CdS core/multicrown NPLs having high quantum yields (> 90%), broad Stokes shifts, and stability proved to be excellent candidates for high-performance LSCs. Here, we demonstrated LSC devices fabricated using these type-II NPLs with varied compositions of CdSe/CdSe1-xTex/CdSe/CdS (0.3 ≤ x ≤ 0.6). The best-performing fabricated LSC exhibits an optical power conversion efficiency of 7.29%, the highest reported thus far for NPLs. Thanks to their scalability and affordability, these type-II NPLs hold great promise in several applications of LSCs, including those for agriculture in greenhouses, construction of the facades of buildings, and aerospace together with solar panels on satellites and spacecrafts.