Boosted Structural Stability and Interfacial Charge Transfer in C_mO_nCl_k/[FA,MA]Pb_1+yI₃ Heterostructures

Abstract

We reported the first-principles computational study of the atomic-scale mechanism underlying the properties of C m O n Cl k /[FA,MA]­Pb1+y I3 heterostructures composed of graphene-related materials C m O n Cl k and formamidinium and methylammonium lead halide perovskites [FA,MA]­Pb1+y I3 (denoting [CH­(NH2)2, CH3NH3]­Pb1+y I3) with a Pb-rich surface that accounts for the proportion factor “y” of Pb. By investigating the structural and electronic properties, the charge carrier transfer, and the quantum transport of electrons, we revealed that among those graphene-related materials, chlorinated graphene oxide (Cl-GO) has the greatest positive effect on both the charge transfer and extraction rates and the stability of perovskite-based photovoltaics. In addition, our study shows that there are intermediate bands generated near the interfaces in Cl-GO/[FA,MA]­Pb1+y I3 heterostructures, which extend the light absorption from the visible light region to the infrared region, enhancing the capability of light absorption of perovskite solar cells.

Surface‐Stabilized CsPbI3 Nanocrystals with Tailored Organic Polymer Ligand Binding

“…In these two cases, the Pb atom is the preferred adsorption site. Charge redistribution mainly occurred near the bond region of the ligand [44] . Moreover, it was found that the binding energy of the CsPbI 3 NCs passivated by the HOPS ligand (1.88 eV) was much higher than that of the NCs passivated by the OA ligand (0.62 eV).…”

“…Charge redistribution mainly occurred near the bond region of the ligand. [44] Moreover, it was found that the binding energy of the CsPbI 3 NCs passivated by the HOPS ligand (1.88 eV) was much higher than that of the NCs passivated by the OA ligand (0.62 eV). Such higher bonding strength between HOPS and CsPbI 3 NCs is less likely to cause ligand dissociation, thus avoiding the additional surface defects and structural deformation, which is conductive to maintaing the stability of CsPbI 3 NCs.…”