Upconversion Nanoparticle Driven Solar Spectrum Conversion for Next-Generation Smart Photonic Windows

This study aims to enhance solar energy harvesting by using upconversion (UC) nanoparticles in luminescent solar concentrators (LSCs) to convert near-infrared (NIR) light into visible light, thereby improving the efficiency of solar cells. Fluoride host matrix NaYF 4 codoped with (2.5%) Er 3+ and (5, 10, and 15%) Yb 3+ were synthesized using the hydrothermal method and characterized using various physicochemical techniques like scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, Upconversion luminescence (UCL), Quantum Yield (QY), and Time-resolved Photoluminescence (TRPL) spectroscopy. The optimization was performed for different concentrations of Yb 3+ in NaYF 4: Yb 3+, Er 3+ Upconversion nanoparticles (UCNPs), and found the highest absolute QY for the 10% Yb 3+ doped sample of 1.97%, with the average carrier lifetime of 177 μs. Further, this UCNPs is embedded into the polymer matrix to fabricate the LSC slab with different concentrations of the material into the polymer matrix. The 0.5 wt % UCNPs in the resin matrix give the highest I SC of 22.5 mA when attached to silicon solar cells, with a power conversion efficiency (PCE) of 5.02%. The findings suggest that NaYF 4 -based UCNPs can be highly effective for next-generation smart photonic windows to achieve the target of net-zero energy buildings.