Transparent photovoltaics (TPVs) have emerged to enable deployment over vision glass in building-integrated PV (BIPV) applications where visible transparency and power conversion efficiency (PCE) are equally important. Transparent luminescent solar concentrators (TLSCs) offer a promising approach to achieving high visible transparency due to a simpler module structure in the incident light path. By selectively harvesting ultraviolet (UV) and near-infrared (NIR) wavelengths, TPVs and TLSCs have a theoretical PCE limit of 20.6% for human vision. To date, TLSCs have only reported moderate PCE values with often poor or unreported operational lifetimes. This thesis focuses on modification of various luminophore classes (organic molecules, organic salts, and metal halide nanocluster salts) to provide routes to improve the performance and lifetime of TLSCs and demonstrate future applications in the agriculture sector. Organic cyanine salts are popular luminophore candidates in TLSCs due to highly tunable, selective absorption bands with high demonstrated photoluminescent quantum yield (PLQY) in the visible region. However, they commonly suffer from poor photostability and low PLQY in the NIR region. Here, we demonstrate the surprising impact of anion exchange to dramatically enhance the lifetime of cyanine salts in a dilute environment without significantly altering the bandgap or PLQY. This enhancement results in an extrapolated lifetime increase from 10s of hours to over 65,000 hours under illumination. Using a combination of experiment and DFT computation, we demonstrate that lower absolute cation-anion binding energies generally lead to greater photostability. We then used this model to predict the stability of other anions. Next, a class of donor-acceptor-donor (DAD) molecules are investigated to begin understanding the relationship between chemical structure and PLQY. Within this DAD class, we demonstrate a dramatic correlation between solvent environment and DAD PLQY, resulting in dramatic enhancements in PLQY with values close to 1.0. We fabricate LSCs using these DADs to report the highest single-component device performance to date. Metal halide nanoclusters, which are precisely defined in their chemical structure, have recently been shown by our group to be a promising UV-absorbing luminophore. By changing transition metal from Mo (group 6) to Ta or Nb (group 5), the bandgap and absorption bands shift dramatically with distinct transitions present in the NIR, making them of even greater interest for TPVs and TLSCs. We explore the photophysical properties of these new compounds, contrasting them with the Mo-based clusters, and discuss pathways for TPV and TLSC integration. Finally, we demonstrate the first plant-transparent PVs highly suitable for agricultural applications. This will initiate a new field of “transparent agrivoltaics” where the tradeoff between plant yield and power production can effectively be eliminated. We first studied the effects of varying light intensity and wavelength-selective cutoffs on commercially important crops (basil, petunia, and tomato). Despite the differences in TPV harvester absorption spectra, photon transmission of photosynthetically active radiation (PAR; 400-700 nm) is the most dominant predictor of crop yield and quality, indicating that the blue, green, and red wavebands are all essentially equally important to these plants. When the average photosynthetic daily light integral exceeds ~12 mol·m-2·d-1, basil and petunia yield and quality are acceptable for commercial production. However, even modest decreases in TPV transmission of PAR reduce tomato growth and fruit yield. The results identify the necessity to maximize transmission of PAR to create the most broadly applicable agrivoltaic panels for diverse crops and geographic locations. We determine that the deployment of 10% PCE, plant-optimized TPVs over approximately 10% of total agricultural and pastureland in the U.S. would generate 7 TW, nearly double the entire energy demand of the U.S.
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