The effectively optical emission modulation in perovskite MAPbBr3 crystal by hot-electron transfer from metals

Abstract

Optical emission modulation is an effective way to improve material properties and to enlarge their applications. However, a significant problem still facing challenge is low efficiency in optical emission enhancement. To contribute this, this work aims to achieve efficient hot electron transfer resulting emission enhancement used the help of plasmon resonance near-field enhancement and combined with excitation energy. Thus, a simply method of metal-perovskite heterojunctions preparation was conducted. The optical crystal of Au nanoparticles/nanocages attached on perovskite MAPbBr3 (NP-C) is presented. The hot electron transfer signal in ion’s vibration is characterized by XRD and Raman spectrum firstly. The cube shape and size distribution mostly in 550–850 nm morphology is revealed by SEM. The carrier concentration is improved about 37.5%, the mobility and resistivity are lowered around 53.2% and 26.7% after soaking in solution, respectively. What’s importantly, the effective modulation of intensity and peak position are achieved at room temperature, which is caused by the behavior of hot-electrons transfer suggested by FDTD simulation. The evidence for hot-electron transfer at the interface in Au–MAPbBr3 in 150 fs are proved by transient absorption spectrum. Finally, the mechanism of optical modulation, band gap structure and hot electrons transfer are depicted. This paper can provide experimental reference for emission enhancement and the development of devices based on hot electrons transfer.