Direct Laser Writing of ?- to ?-Phase Transformation in Formamidinium Lead Iodide.

ABSTRACT: Organolead halide perovskites are increasingly considered for applications well beyond photovoltaics, for example, as the active regions within photonic devices. Herein, we report the direct laser writing (DLW: 458 nm cw-laser) of the formamidinium lead iodide (FAPbI₃) yellow ?-phase into its high-temperature luminescent black ?-phase, a remarkably easy and scalable approach that takes advantage of the material's susceptibility to transition under ambient conditions. Through the DLW of ?-FAPbI₃ tracks on ?-FAPbI₃ single-crystal surfaces, the controlled and rapid microfabrication of highly luminescent structures exhibiting long-term phase stability is detailed, offering an avenue toward the prototyping of complex perovskite-based optical devices. The dynamics and kinetics of laser-induced ?- to ?-phase transformations are investigated in situ by Raman microprobe analysis, as a function of irradiation power, time, temperature, and atmospheric conditions, revealing an interesting connection between oxygen intercalation at the surface and the ?- to ?-phase transformation dynamics, an insight that will find application within the wider context of FAPbI₃ thermal phase relations.

SUBMITTER: Steele JA 

PROVIDER: S-EPMC5595358 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature