Fig. 2From: High-Hole-Mobility Metal–Organic Framework as Dopant-Free Hole Transport Layer for Perovskite Solar CellsCharacterization of optical and electrical properties of Ni3(HITP)2 film. a Optical transmission spectra of different thickness of Ni3(HITP)2 films; b UPS spectra of Ni3(HITP)2 film; c Energy level alignment diagram of PSCs and d The steady-state PL spectra of perovskite films on different thickness Ni3(HITP)2 filmsBack to article page