Self-assembling perovskite films could provide a viable material for use in LEDs. Potential commercial applications include lighting, lasers, and television and computer screens.

The self-assembly technique, developed by Princeton University scientists, overcomes a problem that has limited use of perovskites in LED lights. The self-assembly technique yields uniform, ultra-fine-grained films, where previous fabrication processes have not.

Potential commercial applications include lighting, lasers, and television and computer screens.Perovskites, a crystalline mineral first discovered in Russia in the mid-1800s, exhibit several useful properties. For example, they can be superconductive or semiconductive, a useful characteristic for use in electrical devices. One potential application is as a less-expensive replacement for silicon in solar panels.

The standard current process for creating perovskite film involves dissolving perovskite precursors in a solution with a metal halide and an organic ammonium halide. The crystals in the resulting film are too large, making them inefficient and unstable.

The Princeton team’s process starts with the standard mixture and adds another type of organic ammonium halide. The additional ingredient restrained crystal formation so that the final product has much smaller crystals (around 5-10 nanometers across), creating a thinner, smoother, and more stable film.

The perovskite film is a potential lower-cost alternative to gallium nitride (GaN) in LED bulb manufacture. Lower-cost bulbs could lead to wider adoption of the durable, energy-efficient technology.