Effect of distributed Bragg reflectors on photoluminescence properties of CH 3 NH 3 PbI 3 film

The nanoporous (NP) GaN distributed Bragg reflector (DBR) was prepared by using electrochemical etching. Then the NP-GaN DBR was pretreated by using ozone treatment. Atomic force microscopy and X-ray diffraction (XRD) were used to investigate the influence of ozone treatment on the structure of the substrates. The hybrid organic–inorganic CH 3 NH 3 PbI 3 perovskite films were grown on the NP-GaN DBR and reference substrates by using a one-step solution method. The XRD and field emission scanning electron microscopy test results indicate the high quality of the prepared CH 3 NH 3 PbI 3 perovskite films. The photoluminescence intensity of the prepared CH 3 NH 3 PbI 3 perovskite film on the NP-GaN DBR substrate is ~ 3.5 times higher than that of the film on the reference substrate, with a 3.6 nm spectral blue-shift. The enhancement should be contributable to amplify spontaneous emission by resonant cavity, while the blue-shift could be contributable to stoichiometric difference of the films on different substrates.