Our joint research on quantum well-based red light-emitting diodes was recently published in InfoMat. This paper develops a colloidal quantum well light-emitting diode with long-wavelength emissions. The research significantly improved charge balance within the device by designing and implementing a triple-hole transport layer structure that effectively regulates the internal charge distribution. The fabricated quantum well films exhibit high photoluminescence quantum yield. The resulting LEDs demonstrated high external quantum efficiency, high luminance, extremely low efficiency roll-off, and excellent color saturation and stability. This charge regulation strategy was proven to be universal, effectively enhancing the performance of other-color quantum well LEDs and even quantum dot LEDs. This work provides a new approach and an effective charge management method for developing high-performance two-dimensional nanocrystal LEDs, particularly in the long-wavelength emission region.
Paper Link：https://doi.org/10.1016/j.nanoen.2025.111026