Fig. 1: Molecular design and theoretical mechanism of MBC.

a The chemical structure of benzoic acid (core), p-aminobenzoic acid (lower left) and MBC (lower right); the interaction between PbI2 and benzoic acid (upper left), as well as the benzoic acid anion (upper right). The red value corresponds to the pKa of the functional group, while the blue value represents the pKa of its conjugated acid. b The ESP images and calculated dipole moments of MBC, MBC- and MBC+-. c The calculated binding energies between MBC and several interacting species. The effect of MBC on the (d) defect formation energy and (e) DOS of various defects.