X-ray photoelectron spectroscopy (XPS) analyses were conducted to understand the coordination environment within the Zn2(bim)4 film (Supplementary Fig. ). The high-resolution spectrum of Zn2p (Fig. ) displays two prominent peaks corresponding to Zn2p 1/2 (1023.7 eV) and Zn2p 3/2 (1046.7 eV). Each main peak can be further resolved into two subpeaks representing fully coordinated (1023.7 eV and 1046.7 eV) and unsaturated zinc (1025.1 eV and 1048.52 eV) . This distinction arises when either the crystal terminates with zinc at its edge or grain boundary or defects are generated due to the absence of the bim linker in the ZnN4 tetrahedra .