Self-Encapsulable Carbon Electrode for Efficient and Stable Perovskite Solar Cells

Since the perovskite solar cell (PSC) is emerging as a next-generation photovoltaic, the counter electrode takes a significant role in the commercializing process. Not only the nature abundancy of carbon, but also the proper electronic property and flexibility allow the carbon electrode as a strong candidate for the future electrode. Herein, heat, moisture, and light-resistive electrode-based PSCs are fabricated via tailored elastomer and carbon materials. For device applicable perspective and to fabricate encapsulative electrode, carbon paper and paste obtaining elastomer-based binder (polyisobutylene) are utilized together; both J–V performance up to 17% and long-term stability are enhanced compared to the single-paste system. To confirm the hydrophobicity with encapsulating ability, a direct water-dipping test is conducted and negligible power conversion efficiency (PCE) loss is observed. Last but not least, the optimized device without extra encapsulation exhibits robust stability under harsh conditions retaining ≈80% of initial PCE for 750 h (60 °C and 1 sun), which paves the new concept of carbon electrode as an electrode itself and encapsulating material at the same time.