{Reference Type}: Journal Article
{Title}: Efficient Quasi-2D Perovskite Based Blue Light-Emitting Diodes with Carbon Dots Modified Hole Transport Layer.
{Author}: Wang H;Zhang B;Wang B;Bai S;Cheng L;Hu Y;Lu S;
{Journal}: Nano Lett
{Volume}: 0
{Issue}: 0
{Year}: 2024 Jul 2
{Factor}: 12.262
{DOI}: 10.1021/acs.nanolett.4c02110
{Abstract}: Quasi-2D perovskites based blue light-emitting diodes (LEDs) suffer from its poor electroluminescence performance, mainly caused by the nonradiative recombination in in defect-rich low-n phases and the unbalanced hole-electron injection in the device. Here, we developed a highly efficient quasi-2D perovskite based sky-blue LEDs behaving recorded external quantum efficiency (EQE) of 21.07% by employing carbon dots (CDs) as additives in the hole transport layer (HTL). We ascribe the high EQE to the effective engineering of CDs: (1) The CDs at the interface of HTLs can suppress the formation of low-efficient n = 1 phase, resulting a high luminescence quantum yield and energy transfer efficiency of the mixed n-phase quasi-2D perovskites. (2) The CDs additives can reduce the conductivity of HTL, partially blocking the hole injection, and thus making more balanced hole-electron injection. The CDs-treated devices have excellent Spectral stability and enhanced operational stability and could be a new alternative additive in the perovskite optoelectronic devices.