Exotic silicon-based materials from high-pressure synthesis" hexagonal Si-4H for photovoltaic applications

Speaker:  Silvia Pandolfi, Sorbonne Université (IMPMC)

Program Description:
Synthesis of exotic forms of silicon (Si) with enhanced optoelectronic properties is one of the main challenges for current technology. Careful design of high-pressure (HP) pathways can lead to the stabilization of new materials with novel properties. In this work, we use in-situ x-ray diffraction to investigate Si transition mechanisms at high-pressure and, with these new insights, we synthesize and characterize new Si-based materials. We provided the first synthesis of pure hexagonal Si, a promising candidate for photovoltaic applications. Our structural characterization reveals a hierarchical nanostructure that is expected to increase its potentiality for solar energy conversion, and that could enable design and engineering of nano-patterned devices.