Most optoelectronic devices, such as light-emitting diodes (LEDs) and solar cells are based on inorganic semiconducting materials. These crystalline semiconductors suffer from impurities and traps at crystal domain boundaries. Therefore, they need to be prepared as highly pure, ordered crystalline structures which requires expensive processing methods. Metal halide perovskite semiconductors are different as they have a very high defect tolerance. That is, polycrystalline films with multiple crystal domain sizes maintain high carrier mobilities and diffusion lengths. Therefore, they can be processed using simple and economic coating methods such as solution casting and sublimation. These materials are very promising for large area LEDs and solar cells enabling the reduction of electricity consumption and the generation of green electricity. The luminescence properties of metal halide perovskite films, however, are affected by the defects. This reduces the achievable efficiency in the solar cells and LEDs.
It is therefore, important to understand the relation between the perovskite structure and the luminescent properties. HELD’s main objective is the engineering of highly luminescent multiple layered heterostructures of defect tolerant perovskite semiconductors and their integration into highly efficient planar/thin film LEDs, solar cells and lasing devices.
To achieve this overall objective HELD is organized in three blocks: 1) aiming to improve the synthetic routes and processing methods to obtain high quality thin films without the use of harmful solvents. 2) using these novel preparation methods to design and develop highly emissive perovskites. 3) integrate these thin films into planar LEDs, solar cells and lasing devices.