Absorbing Horizons: A study on strongly absorbing luminescent thin films for luminescent solar concentrator applications

The topic of this thesis pertains to researching novel materials for luminescent solar concentrator (LSC) applications. An LSC, as the name suggests, concentrates solar radiation incident on a large surface area to a smaller surface area. First conceptualized in the 1970’s, LSCs can be used in conjunction with solar cells to create a so-called ‘electricity generating window’. Fast-forward 50+ years and the electricity generating window is yet to be commercialised. In Chapter 1 the motivation behind developing LSCs and their operating principles is introduced along with obstacles that must be overcome in order to mass adopt this technology. For example, from basic calculations, it can be shown that in order for an electricity generating window to obtain a commercially interesting power output of >100 W/m2 it is necessary to absorb at least 50% of both the ultraviolet (UV) and visible (VIS) part of the solar spectrum. Absorbing only a part of the VIS spectrum does not only lower output but will also lead to unwanted colorization of the window. Another obstacle that is often overlooked is complying with glass-industry practises which limits synthesis methods to create LSCs. Reactive magnetron sputtering is a technique for synthesizing thin films that is up-scalable and already a standard practise in the glass industry. Sputtering is therefore the synthesis method of choice in all the work presented. The key challenge addressed in this thesis is in obtaining thin films with a thickness of a micron or less that meet the absorption and luminescence requirements for efficient LSCs.....