Improving Device Performance of PbS Quantum Dot Solar Cells Using Inorganic Hole Transport Layers
Colloidal quantum dots (CQDs) are nanometer-scale semiconductor crystals. These "quantum dot" materials exhibiting three dimensional (3-D) confinement, are highly desired for their size-tunable optical properties synthesis routes utilizing organo-metallic precursors enable the production of nanocrystalline particles with nearly monodisperse size dispersions. I improved the efficiency of the colloidal PbS quantum dot solar cell efficiency by varying the device structure with the help of an inorganic hole transport materials like 2D-MoS2 nanosheets and by changing the chemical nature of the QD surface by ultraviolet ozone treatment (UVO). UVO treatment for few seconds lowers the Fermi energy level and increases p-doping through control oxidation of the PbS QD surface. I developed a two-stage solution-phase ligand exchange process by substitution of the organic counter cation with the inorganic metal cation is achieving superior stability and performance of the CsI and NaI treated PbS quantum dot solar cells.