ERC Starting Grant for perovskite researcher Prof. Michael Saliba

Perovskites, named after the Russian mineralogist Lev Perowski, are a new class of inexpensive semiconductors that have the breakthrough potential to generate and use energy in a highly efficient manner. Thin perovskite films are isolated by converting a liquid ink into a solid using a special drying process.

However, current crystallization methods for this liquid-to-solid phase transition often result in uncontrolled film growth that is not homogeneous in appearance, but has ragged grain boundaries of different sizes - similar to a mosaic. Undesirable effects often occur at the boundaries of these plates or grains, such as the penetration of water from the atmosphere. A lack of high-quality materials with large, controlled grains hinders the development of solution-processed semiconductors. In this context, Michael Saliba's LOCAL-HEAT project (Controlled Local Heating to Crystallize Solution-based Semiconductors for Next-Generation Solar Cells and Optoelectronics) seeks to use light to control the fundamental nucleation and crystallization kinetics of semiconductor films when transitioning from the liquid precursor to the final solid-state. This light will create local heat packages that will result in controlled grains and thin films.

Saliba intends to achieve local heating by developing two new methods: firstly, with laser beams that can be precisely adjusted in terms of location, and secondly, through the so-called thermoplasmonic heating of metallic nanoparticles. These act as intensifying antennas that turn incoming light into localized heat.

This new method will enable the development of perovskite solar cells that are highly efficient and that remain stable over several decades. Saliba is convinced that, "LOCAL-HEAT will thus revolutionize the production of solution-based materials and enable the development of new key technological applications in optoelectronics and medical technology,". As a scientist, he is already considering new types of solar cells, light-emitting diodes, detectors and much more besides.

COMPAMED-tradefair.com; Source: University of Stuttgart