Charge Transfer Dynamics of Two-Dimensional Ruddlesden Popper Perovskite in the Presence of Short-Chain Aromatic Thiol Ligands

Abstract

Two-dimensional (2D) Ruddlesden Popper perovskites (RPP) are highly important in light-harvesting and photovoltaic applications. The formation of a repetitive quantum well structure by alternating organic and inorganic layers leads to dielectric confinement of charges, which essentially inhibits the effective charge transport. In this work, we have investigated the impact of bifunctional short-chain aromatic ligands, namely, 4-aminothiophenol (ATP) and 4-nitrothiophenol (NTP), on the charge transfer dynamics of 2D RPP. The electron transfer from 2D RPP to NTP and the hole transfer from 2D RPP to ATP are evident from ultrafast transient absorption spectroscopy, depending on the nature of ligands, and the electron transfer and hole transfer occur in 900 fs and 1.9 ps, respectively. Our results provide insights for understanding the charge transfer dynamics in the presence of short-chain aromatic thiol ligands with 2D RPP, which will facilitate the performance of next-generation optoelectronic devices.