A Cd-based MOF: iodine capture and enhanced efficiency of perovskite solar cells

In this work, a Cd-based metal-organic framework (MOF) {Cd(H₂L)₂} (Cd-MOF) (L = 5-(3-carboxypyridin-4-yl)isophthalic acid) has been synthesized solvothermally and characterized. The nitrogen-containing π-electron-rich moieties render Cd-MOF an ideal platform for iodine uptake. Its static adsorption and adsorption kinetics were also investigated. The Cd-MOF efficiently captures iodine and removal efficiency was achieved at 68.6% after 40 h. Furthermore, the Cd-MOF was chosen as the interfacial modification material between the perovskite layer and hole transport layer in the perovskite solar cells (PSCs), Cd-MOF can passivate surface defects and promote hole extraction. Consequently, the Cd-MOF-modified PSCs yield enhanced power conversion efficiencies (PCEs) of 23.71%, outperforming the reference PSCs (21.68%).