Ethacridine lactate additive engineering for defect passivation in HTL-free carbon electrode perovskite solar cells

Hole-transport-layer (HTL)-free carbon electrode perovskite solar cells (C-PSCs) are promising candidates for low-cost photovoltaic applications, but their performance is still limited by defect-induced recombination and insufficient long-term stability.

Bonsu et al. recently proposed the use of ethacridine lactate (EAL) (C₁₅H₁₆N₃O₄) in the preparation of the solution containing perovskite precursors as an additive in carbon electrode HTL-free mixed organic–inorganic PSCs. In contrast to the previous study mainly focused on inverted inorganic PSCs, this research reveals that the EAL-modified films have improved morphology and reduced defect density, resulting in enhanced photovoltaic performance. The optimized device delivers a power conversion efficiency of 16.54% and retains 80% of its initial efficiency after 1200 h without encapsulation. This work highlights an effective additive-engineering strategy for achieving efficient and stable HTL-free carbon electrode PSCs, which is reported by Frontiers of Materials Science.