Solution-processed halide perovskites are photoactive materials that may be used to produce low-cost, high-performance optoelectronics. For example, perovskite-based solar cells having efficiencies of at least 20 %, and perovskite-based light emitting diodes (PeLEDs) having high brightness and tunable color across the entire visible range have been produced. PeLEDs typically include organic-inorganic hybrid perovskites, such as CH3NH3PbBr3, as emitters.
This technology comprises films, PeLEDs, and methods of making films that address disadvantages experienced in this field. In some embodiments of the technology, the methods include providing a precursor formulation that includes an all-inorganic perovskite, a polymer, and a liquid, wherein the weight ratio of the polymer to the all-inorganic perovskite in the precursor formulation is about 0.02:1 to about 0.5:1; and casting the precursor formulation to form a film comprising the all-inorganic perovskite.
In another aspect, light emitting diodes are provided that include an all-inorganic perovskite-based film. The light emitting diodes include an anode; a cathode; and a light emitting layer arranged between the anode and the cathode, wherein the light emitting layer includes an all-inorganic perovskite-based film as provided herein. In some embodiments, the light emitting diode has a photoluminescence quantum yield of at least 50 %, or at least 60 %.
Advantages
- Excellent performance including brightness and efficiency
- Low-cost
- High-stability
