Advanced interfacial layers and encapsulation techniques significantly enhance the stability of perovskite solar cells (PSCs) by addressing intrinsic and extrinsic degradation pathways that typically limit their operational lifetime.
How Advanced Interfacial Layers Improve Stability
- Chemical Passivation and Defect Reduction: Interfacial layers can chemically passivate defects at the interfaces between the perovskite absorber and charge transport layers. This reduces non-radiative recombination and hinders ion migration—both key factors in device degradation. For example, applying organic molecules for passivation at interfaces has been shown to improve both efficiency and stability.
- Material Replacement in Hole Transport Layers (HTLs): The choice and modification of hole transport materials (HTM) impact device stability. Replacing traditionally used lithium salts (like LITFSI) with spiro-based HTMs or hydrophobic HTMs drastically improves moisture resistance and reduces corrosive effects, leading to better device longevity.
- Structural and Compositional Modifications: Using mixed cations and halides in the perovskite layer in concert with well-designed interfacial layers can create more robust crystal structures and interfaces. These combined approaches minimize environmental degradation and structural breakdown at interfaces.
Role of Encapsulation Techniques
- Environmental Protection: Encapsulation physically shields the perovskite layer from moisture, oxygen, and other environmental stresses that cause rapid degradation. Advanced encapsulation materials and coatings, especially chemically reinforced protective layers, can triple or more the operational stability of PSCs under real-world conditions without sacrificing efficiency.
- Mechanical and Chemical Barrier: Encapsulation also provides mechanical protection against physical damage and suppresses the ingress of corrosive species that might originate from adjacent layers or the environment.
Summary Table
| Improvement Mechanism | Description | Impact on Stability |
|---|---|---|
| Interfacial passivation | Organic molecules or dopants reduce defects and recombination | Reduces ion migration, increases lifetime |
| HTL material optimization | Replace lithium salts with hydrophobic or spiro-based HTM | Enhances moisture resistance, reduces corrosion |
| Mixed cation/halide perovskite | Strengthens crystal structure and interface robustness | Improves intrinsic material stability |
| Advanced encapsulation coatings | Chemically reinforced protective layers | Protects from moisture, oxygen, mechanical damage; triples stability |
By combining advanced interfacial layers that improve electronic and chemical stability with state-of-the-art encapsulation techniques that provide robust environmental protection, researchers have made significant strides in overcoming the stability challenges that hinder the commercialization of perovskite solar cells.
This integrated approach enables PSCs to maintain high efficiency while enduring the moisture, heat, and mechanical stresses of real-world operation, moving the technology closer to practical and widespread deployment.
Original article by NenPower, If reposted, please credit the source: https://nenpower.com/blog/how-do-advanced-interfacial-layers-and-encapsulation-techniques-improve-the-stability-of-perovskite-solar-cells/
