Hot carrier dynamics in the BAPbBr/MoS heterostructure.

Herein, we investigated the carrier-phonon relaxation process in a two-dimensional (2D) BAPbBr perovskite and its heterostructure with MoS. Energy transfer was observed in the van der Waals heterostructure of 2D perovskite and monolayer MoS, leading to enhancement in the photoluminescence intensity of MoS. Femtosecond pump-probe spectroscopy was used to study the carrier and lattice dynamics of pristine 2D materials and their heterostructure. A generalized two-temperature model was introduced to include competing effects of electron cooling in the rate equation of electron and lattice relaxation dynamics. The hot phonon bottleneck effect is more enhanced in the BAPbBr/MoS heterostructure than in pristine BAPbBr, resulting in a longer electron relaxation time. By developing a heterostructure platform with 2D BAPbBr and MoS hybrid materials, this work provides a unique opportunity to understand and tailor carrier dynamics, interfacial coupling, and long-lived hot electrons, ultimately enhancing the efficiency of optoelectronic devices.