Significant breakthroughs in interface engineering for high-performance colloidal QLEDs: a mini review

Abstract Substantial effort has been devoted to the fabrication of charge transport and injection layers for better colloidal quantum dot light-emitting diodes (QLEDs). Recent cutting-edge fabrication methods of charge transport and injection layers are regarded as very promising ways to realize high-performance colloidal QLEDs. The interface engineering of the functional layers plays a critical role in raising the QLED’s efficiency and stability. This mini review summarizes current research on (i) electron transport layers that restrain luminescence quenching at the interfaces between the functional layers and quantum dots; (ii) hole injection layers with a tunable work function for high hole mobility of a device; and (iii) hole transport layers with low electron affinity and reduced energetic disorder for hole injection, which are directly linked to QLED luminescence performance. The most cutting-edge progress on the interface engineering of colloidal QLEDs is briefly highlighted. Perspectives and suggestions are provided to guide device development. This featured review raises awareness of the significance of charge transport and injection layers and reveals their critical roles in colloidal QLEDs.