Addressing the efficiency loss and degradation of triple cation perovskite solar cells via integrated light managing encapsulation

Here, we present a holistic encapsulation method for perovskite solar cells to address both optical performance loss at the air-cell interface as well as intrinsic and extrinsic stability challenges. Our one-step method provides shielding to PSCs from oxygen and moisture-induced degradation as well as in-situ patterning for light management. As a result of embedding the anti-reflective coating onto the front side of the cell, the power conversion efficiency (PCE) of the PSCs was increased from 14.1± 0.8% to 15.6± 0.8%, indicating an 8% relative improvement. Moreover, the encapsulated devices kept their initial performance after 90% relative humidity and water immersion tests. The outdoor exposure test showed no degradation for the encapsulated cells after 24 hours of resting at -17°C and maximum wind speeds of 7 m/s on average. Additionally, the encapsulation strategy was instrumental in mitigating oxygen and humidity-induced degradation during ISOS-LC tests, retaining up to 80% of the initial performance for the encapsulated devices after 360 hours. This research establishes in-situ encapsulation and patterning as a promising solution for reducing optical losses and extrinsic instabilities in PSCs. The choice of flexible encapsulant enables it to be used for both rigid and flexible PSCs in a wide range of applications. • The perovskite solar cells (PSC) were simultaneously patterned and encapsulated. • The surface pattern mimicking leek introduced haze and antireflection to the cells. • The efficiency increased by 8% ± 0.8% when leek surface pattern was employed. • The PSC devices were successfully protected against moisture and oxygen.