Recent trends of oxides heterostructures based upconversion phosphors for improving power efficiencies of solar cells: A review

Upconversion (UC) technology harvests near infrared (NIR) radiation from the sun and has been widely used to enhance the solar cell's efficiency in the past few years. One key problem limiting the efficiency of solar cells is inadequate solar energy harvesting, which is caused by a mismatch between photon energy distribution and semiconductor material or dye absorption. Light-conversion phosphors have been investigated as spectral converters to improve the light-harvesting performance of solar cells. Upconversion nanoparticles (UCNPs) are a type of optical nanomaterial capable of converting low energy photons to high-energy emissions. The mechanism for better NIR light-harvesting UCNPs-based nanocomposites n-n heterostructures, as well as ternary UCNPs manufactured with diverse phosphors, were thoroughly reviewed, the review paper also emphasizes several unique concepts in solar cell development. Bottom-up and top-down methods for the preparation of upconversion nanophosphors were reviewed. The effect of host lattices on upconversion luminescence properties was reviewed for various solar cell applications. The enhancement of UC characteristics using triple doping of alkali ions was also reviewed. Numerous strategies to integrate the UC phosphors with solar cells were reviewed.