Assembly of Fe(III)‐Grafted Metal–Organic Complexes as p‐Type Dopants for Efficient and Stable Perovskite Solar Cells

Realizing the rapid/controllable oxidation of 2,2′,7,7′‐tetrakis( N , N ‐di‐ p ‐methoxyphenylamine)‐9,9′‐spirobifluorene (Spiro‐OMeTAD) under an inert atmosphere, reducing the J–V hysteresis and enhancing the air stability of devices is extremely significant to fabricate high‐performance perovskite solar cells (PSCs). Herein, the Fe(III) ion grafted metal–organic complexes (Fe(III) ⊂ MOCs) are assembled and used as the p‐type dopants of hole transport layers (HTLs) to prepare efficient and stable PSCs. Consequently, the optimal Fe(III) ⊂ In‐2‐bpydc‐doped device presents a significantly enhanced power conversion efficiency (PCE) of 20.46%, benefitting from the improved hole extraction and weakened carrier recombination at the interface between HTLs and perovskite films. More importantly, the modified device possesses a reduced J–V hysteresis index (HI) of 0.094, and can maintain nearly 90% of its initial PCE value after being exposed to the air at ≈25 °C and relative humidity (RH) of ≈35% for 4 weeks, which is attributed to the restrained detrimental penetration behavior by the MOC carrier part of dopants. This work is of important guiding significance for the application of MOC materials in photovoltaic fields.