Perovskites and gallium nitride (GaN) are two important materials for research into devices like LEDs. GaN is already the basis for the commercial white LED industry. Perovskites have great flexibility and could make brilliant devices, but currently suffer from a short lifetime, as they degrade in air. By porosifying GaN and depositing perovskite into the pores we have created a hybrid optical material that offers a method for combining the advantages of the two materials to potentially make novel, long lasting LEDs.

We have shown that we can make perovskite in the pores that emits light through photoluminescence. We see that the size of the pores affects the size of the perovskite regions in a way that can be used to change the colour of the light. The structure still emits light a year after the structure was made, when comparable perovskite without the pores loses its light emission after only 10 days.

Figure caption: Using an electron microscope we can show the porous GaN structure in cross-section (a). By measuring the X-rays emitted by the material, we can draw maps of where different elements are (b-d), which suggests that Pb and Br are in the pores of the GaN.