A Metal-Free Phthalocyanine Additive for Defect Passivation and Processing Tolerance in High-Efficiency Perovskite...

Metal-free phthalocyanines (Pcs) have rarely been explored in perovskite solar cells (PSCs) due to poor solubility and limited processability. Here, we introduce CG-0, a fully substituted metal-free Pc bearing peripheral chlorine atoms and non-peripheral ethoxy chains that confer exceptional solubility, near-infrared absorption, and photochemical robustness. As an additive in wide-bandgap (WBG) PSCs, CG-0 promotes high-quality crystallization, passivates defects, and suppresses non-radiative recombination. Strikingly, ultra-high doping levels (1.75 mm) are tolerated without performance loss, yielding a PCE of 20.41% with an FF of 83.2% under AM 1.5G, and a PCE of 38.60% with an FF of 82.2% under 1000 lux white LED. At high loadings, CG-0 also imparts a vivid, tunable film color, enabling aesthetic and multifunctional device designs. This work establishes a rational molecular design paradigm in which solubility-driven processability, multi-point defect passivation, and interfacial stabilization are integrated into a single additive. The approach not only delivers record WBG PSC efficiencies under both solar and indoor light, but also breaks the constraint of fixed device appearance, opening avenues toward efficient, color-adaptive perovskite photovoltaics.