Enhanced Efficiency and Moisture Stability of Dopant-Free P3HT Perovskite Solar Cells via a Tricarboxytriphenylamine Molecular Lock

, leading to superior defect passivation and more favorable energy-level alignment at the interface. As a result, TCTA-treated devices exhibit significantly enhanced charge extraction, reduced nonradiative recombination, and improved operational stability. Benefiting from these synergistic effects, the power conversion efficiency of dopant-free P3HT-based PSCs is boosted from 12.66% to 17.17% and 19.68% for TPA- and TCTA-modified devices, accompanied by markedly improved moisture stability and long-term durability. This work provides a promising molecular design principle for constructing high-performance and stable dopant-free P3HT-HTL-based PSCs.