Suppression of Surface Degradation of PbS Quantum Dot Solar Cells Using Ultrafast Flash Lamp Annealing
발표자
()
초록
내용
PbS colloidal quantum dot solar cells (PbS CQDSCs) have advantages like multiple exciton generation, bandgap tunability and absorption of short wavelength infrared light. Despite these merits, the PbS quantum dots are vulnerable to formation of surface defects that can degrade the electrical and optical properties of the quantum dots. In the PbS CQDSCs, the fine control of its surface is essential to improve solar cell power conversion efficiency (PCE). In particular, the surface oxidation and hydroxylation of PbS quantum dot (QD) are big issues that cause the mid-gap trap states, leading open circuit voltage (VOC) loss. Also, this can be happened during the PbS QD solid annealing step, one of the inevitable processes to improve charge transport. Our group effectively suppressed the surface oxidation and hydroxylation of PbS QD through ultrafast flash lamp annealing (FLA). Therefore, the VOC was improved from 0.64 V to 0.66 V. And the PCE was 13.5% for a target device.