Luminescent down shifting CdTe colloidal quantum dots for enhancing polycrystalline silicon solar cells

In this paper, CdTe quantum dots (QDs) with emission bands at 762 nm and 812 nm were investigated for their use in luminescent down shifting (LDS) layers. Spectral location of emission bands and quantum yield of luminescence of the QDs in solution proposed that they were suitable nanoparticles for inclusion in LDS layers. QDs were dispersed in poly (methylmethacrylate) (PMMA) polymer matrix and thin films were fabricated approximately of 70 microns. Significant solar cell efficiency enhancements (approximately 5%-10%) under normal (AM1.5, 25 °C) condition were observed after QDs doped PMMA coatings. The experimental results showed increments in the Voc from 478 to 541 mV, Isc from 35 to 42 mA, Jsc from 8.96 to 10.51 mA/sm2, FF from 69.1 to 77.3% and efficiency from 13.12 to 19.48%. PMMA thin film doped with CdTe QDs was spin-coated on the front surface of Si solar cell for enhancing the solar cell efficiency via photoluminescence (PL) conversion and antireflection effects.