Exploring the effect of CH/FBr ( = 0-3) passivating agent on surface properties at different termination ends: first principles.

To prevent further decomposition of organic-inorganic hybrid perovskite by defects, in this work density functional theory was applied to explore the electronic properties, carrier surface mobility and theoretical photoelectric conversion efficiency (PCE) of passivating molecules with different fluorine atom content at the symmetric site of the benzene ring at different termination ends of MAPbI, which shed light on the control of perovskite surface passivation by different element atoms in the same molecule. We found that the same molecule acts as a different passivation agent at different termination faces. Passivating molecules on the surface termination end by MAI play a Lewis acid role, with molecules with stronger dipole moments narrowing the band gap from the original 1.