• Atomically dispersed Co atoms in carbon nanosheets (Co1/CN) effectively adjust interfacial energy levels, reducing charge transport barriers in carbon-based perovskite solar cells.
• The optimized C-PSCs achieve a power conversion efficiency (PCE) of 22.61%, a significant improvement over conventional carbon electrodes.
• Devices maintain 94.4% of initial PCE after 1000 hours of continuous illumination without encapsulation, demonstrating exceptional long-term stability.
• This work introduces a universal method to regulate carbon electrode energy levels, advancing the commercialization potential of perovskite solar cells.