Figure 1. Surface barrier solar cells based on semiconducting PbS quantum dots and quantum confinement effects.

(a) Schematic of metal-PbS QD Schottky junction solar cells (ITO/PbS QDs/LiF/Al). (b) Room-temperature photoluminescence (PL) and attenuance spectra of films assembled with OA-PbS QD with different sizes as estimated using the empirical equation by Moreels et al¹⁸. The size of QDs estimated here is in good agreement with the results obtained from TEM size distribution statistics (see Supplementary information for details). (c) Representative J–V characteristics of QD solar cells in air under AM 1.5 G filtered spectral illumination (100 mW/cm²) with very high FF of > 60%. The inset shows the J–V curve in semi-logarithm scale.