2016/02/10 by Roha Saad, Saad, Roha, Nauman Zafar Butt +1
Engineering · Materials Science · #Chalcogenide Semiconductor Thin Films #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Quantum Dots Synthesis And Properties
paper · pdf · doi:10.48550/arxiv.1602.04236
openalex publication_date 2016/02/10 · openalex created_date 2022/10/03 · openalex updated_date 2026/07/28
We investigate physics based design of colloidal quantum dot (CQD) solar\ncells using self-consistent computational modeling. The significance of band\nalignment engineering and optimized carrier mobility are quantitatively\nexplored as a function of sub bandgap defect densities (Nt) in the bulk CQD.\nFor Nt \≤ 1015 cm-3, band alignment engineering near the interface\nof CQD and the metal contact could significantly improve open circuit voltage\nby suppressing the forward bias dark current. This effect could enhance cell\nefficiency up to ~37% for thinner (< 1 \μ m) CQD layers. For thicker (> 1\n\μ m) CQD layer, the effect of band engineering is diminished as the forward\nbias dark current becomes diffusion-limited and less dependent on the\ninterfacial band offsets. An optimal carrier mobility in CQD lies in the range\n~ 10-2 cm2/Vs - 100 cm2/Vs and shows variation as a function of CQD layer\nthickness and the interfacial band offset. For Nt \≈ 1014 cm-3,\nan optimally designed cell could provide ~20% efficiency under AM1.5G solar\nspectrum without employing advanced structural optimizations such as the\nnanostructured electrodes. These physical insights contribute to a better\nunderstanding of quantum dot solar cell design, allowing a step further towards\na highly efficient and a low cost solar cell technology.\n