Improving the data transmission rates for optical wireless communication by surface passivation of CsPbBr3 quantum dots

Quantum dots (QDs) preserve short photoluminescence (PL) lifetime and are widely developed for optical wireless communication (OWC). However, QDs often suffer from surface defects that limit their performance. In this work, we investigate the impact of post-treatment with didodecyldimethylammonium bromide (DDAB) and ${{\rm PbBr}_2}$ on the OWC performance of ${{\rm CsPbBr}_3}$ QDs. The treatment significantly improves the PL properties, leading to an increased quantum yield of 98% and a prolonged PL lifetime of 1.24 times compared to untreated QDs. As a consequence, the ${-}{3}\;{\rm dB}$ bandwidth and maximum data transmission rates under on–off-keying (OOK) modulation are also enhanced, reaching 0.79 and 1.15 times those of pristine QDs, respectively. This improvement highlights the importance of surface passivation for optimizing ${{\rm CsPbBr}_3}$ QDs in OWC applications.