Coordination polymer based perovskite device: matched energy levels and photocurrent enhancement in the absence or presence of methanol

Abstract

A coordination polymer based perovskite device yielded much larger photocurrent density with or without methanol under visible light illumination, which is ascribed to their matched VBM/CBM energy levels.

Structural Diversity of Copper(I) Cluster-Based Coordination Polymers with Pyrazine-2-thiol Ligand

“…As shown in Figure , 1 – 6 exhibit a stable and clear photocurrent response of 1.59 × 10 –5 , 1 ; 1.12 × 10 –5 , 2 ; 2.07 × 10 –5 , 3 ; 1.39 × 10 –5 , 4 ; 4.45 × 10 –5 , 5 ; and 6.62 × 10 –5 mA cm –2 , 6 , with irradiation of a 50 W LED lamp every 10 s switching cycle (λ = 420 nm). Based on these values, the photocurrent densities can be arranged as 6 > 5 > 3 > 1 > 4 > 2 , which follows the reverse order of their bandgap. , The high photocurrent density of 6 could be explained on the basis of the band gap (1.92 eV, 6 ), which is lower than other compounds (2.03, 1 ; 2.06, 2 ; 2.00, 3 ; 2.05, 4 ; 1.99 eV, 5 ), indicating that the electrons from the HOMO are more easily excited and injected into the LUMO of 6 in contrast to other compounds. Therefore, 6 produces larger current density than other compounds.…”

“…Based on these values, the photocurrent densities can be arranged as 6 > 5 > 3 > 1 > 4 > 2, which follows the reverse order of their bandgap. 65,66 The high photocurrent density of 6 could be explained on the basis of the band gap (1.92 eV, 6), which is lower than other compounds (2.03, 1; 2.06, 2; 2.00, 3; 2.05, 4; 1.99 eV, 5), indicating that the electrons from the HOMO are more easily excited and injected into the LUMO of 6 in contrast to other compounds. Therefore, 6 produces larger current density than other compounds.…”