Description
- Abstract:
- Luminescent Solar Concentrators (LSCs) consist of a thin slab of luminescent composite that absorbs sunlight and re-emits it at a lower energy level, subsequently directing it toward the device's edges, where solar cells collect it. Boasting low cost, flexibility, and functionality in low-light conditions, LSCs hold the potential to enhance solar cell efficiency by decreasing the necessary amount of semiconductor material. However, LSCs are still in the preliminary stages of development and have not yet reached widespread commercialization due to factors such as manufacturing restrictions, performance limitations, and size constraints. Despite these challenges, LSCs show promise as a potentially significant technology for boosting efficiency and reducing solar power costs. In this thesis, the primary focus lies in optimizing LSCs from various angles. Building on the working principle of the LSC device, optimization efforts target aspects such as coating techniques, surface structure, emitter composition, and innovative geometries. By integrating these optimization strategies with simulation studies, enhanced LSC performance can be achieved, paving the way for exploring future developments in the field. Chapter 1 provides a comprehensive introduction to LSCs, encompassing the rationale for their necessity, their optical characteristics, and their potential applications. Additionally, this chapter elucidates the fundamental operating principles of LSCs and offers an overview of the field's developments. Furthermore, it identifies the prevailing limitations and challenges within the domain and outlines potential strategies for addressing these issues, which will be discussed further in the following chapters. Chapter 2 introduces an ultrasonic spray coating technique for creating high-quality QD-LSCs with smooth, customizable layers. This adaptable method reduces QD aggregation and works with various substrates. By adjusting the QD-ink solution, we can fine-tune photon capture, transparency, and solar energy harvesting for QD-LSC devices. This study marks a significant step toward integrating programmable, high-performance LSC devices in diverse applications. Chapter 3 presents a 3D macroporous-structured photonic crystal (PC) coated QD-based LSC (PC-LSC) device, effectively reducing escape cone photon loss. The PC-LSC's light-trapping efficiency increases by ~30% compared to conventional LSCs. Results show significant improvements in external quantum efficiency and concentration factor for large-area PC-LSC devices under sunlight, highlighting their potential in practical solar energy conversion systems with enhanced energy harvesting capabilities. Chapter 4 describes lead-free Cs3Cu2Cl5 perovskite nanodisks (NDs) with high PL QY (84.2%) and a large Stoke shift (1.43 eV). Incorporating these NDs into LSC and LDS devices using an ultrasonic spray coating method, we achieved high visible light transmission, low photon scattering, and superior UV photon harvesting and energy conversion with Si-PV cells. Our research highlights the potential of these unique photon-managing devices for spacecraft photon collection or multifunctional energy collection hulls with increased specific power, paving the way for lead-free perovskite nanomaterials in space-based solar power systems. Chapter 5 demonstrates a mixed-design LSC incorporating high PLQY quantum cutting perovskite Yb-doped CsPbCl3 nanocrystals and Stokes-shift engineered CuInS2/ZnS quantum dots, achieving high ηext performance for large-scale LSC devices through experimental and computational methods. This mixed-design LSC reduces re-absorption losses and scattering attenuation compared to tandem-design LSCs. Our simulations show that the mixed LSC-PV system can significantly reduce energy generation costs, enhancing energy gain in NZEB buildings compared to stand-alone roof-mounted PV panels. This study advances the design and fabrication of LSCs and building-integrated solar windows. In conclusion, Chapter 6 summarizes the whole projects through my Ph.D. studies on LSCs and offers my perspective on the future direction of LSC developments across various aspects. These include potential avenues to improve performance limitations and the exploration of future LSC applications within the solar energy field.
- Notes:
- Thesis (Ph. D.)--Brown University, 2023
Citation
Wang, Junyu,
"Advanced Design and Optimization of High-Efficiency Semiconductor Luminescent Solar Concentrators"
(2023).
Chemistry Theses and Dissertations.
Brown Digital Repository. Brown University Library.
https://repository.library.brown.edu/studio/item/bdr:ms9vanx9/
