基于Mg掺杂载流子产生层的红绿双色可调叠层OLED及其防伪应用

Abstract： Color-tunable organic light-emitting devices (OLEDs) hold significant application potential in dynamic displays， anti-counterfeiting， and information encryption.In this work， a tandem-structured red-green color-tunable OLED is constructed using Bphen∶Mg as the n-doped charge generation layer (CGL).The effects of Mg and Ag dop• ing on carrier injection and recombination behavior in the CGL are systematically investigated.Although Mg doping results in a lower current density， it yields a higher external quantum efficiency (16.9%)， which is more favorable for efficient luminescence.By adjusting the stacking order of the red and green emitting layers， the device with a green-bottom/red-top configuration exhibits pronounced voltage-dependent color tunability.Its CIE coordinates shift from (0. 61， 0. 39) at 7 V to (0. 47， 0. 48) at 19 V， a change that extends beyond the five-step MacAdam ellipse range， ensuring good visual discernibility.Based on this structure， a patterned anti-counterfeiting label is further fabricated， demonstrating dynamic switching between a red pattern at low voltage and a yellow-green background at high voltage， thereby verifying its feasibility for multi-level visual anti-counterfeiting and information encryption.