Atmospheric All‐Solution‐Processed Perovskite Light‐Emitting Diodes

Perovskite light‐emitting diodes (PeLEDs) are generally fabricated in a sandwiched device structure that contains a perovskite emissive layer between the electron transport layer (ETL) and the hole transport layer (HTL). However, protective atmosphere environments are avoidless during the fabrication processes of PeLEDs. Taking the large‐scale industrial production into consideration, all‐solution method‐processed ETL‐free PeLEDs under ambient conditions are still highly demanding. This work successfully demonstrates the optimization of blocking passivation layer ETL‐free PeLEDs by the all‐solution method for manufacturing in ambient conditions. The obtained PeLEDs have a luminance of more than 8200 cd m−2, which is more than 40 times higher compared with the control device. The optimization mechanism of passivation and synergism effects is proposed. These advances can provide an opportunity to fabricate high‐performance perovskite‐based photovoltaic devices under ambient conditions. Herein, the fabrication and measurement of perovskite light‐emitting diodes in atmospheric environments are difficult and pioneering work. More importantly, the mutually synergistic passivation phenomenon of PMMA and PVK are revealed. After adjusting the ratio of the two materials mentioned earlier, a perovskite light‐emitting diode with a luminance of more than 8200 cd m−2 is finally obtained.