Semiconductor nanocrystals (NCs) have become the most important material for colloidal nanophotonics – a rapidly advancing research field, which evolves into a powerful technological platform for lighting, biomedicine, lasing, photovoltaics, etc. This is evidenced by a steadily growing number of companies and start-ups producing and/or using NC-based materials (Nanosys, QD Vision, UbiQD, UbiGro etc.) and has led to the appearance of the consumer products – displays from Sony, TCL, and Samsung. By some estimates, such displays have higher luminance and are 25 % more efficient than organic LEDs, and by 2025 60 % of TVs and 50 % of monitors may include NC-based materials. However, most of the success was achieved with the NCs composed of cadmium chalcogenides, which became a severe obstacle with the tightening of restrictions on the use of toxic materials in consumer products. This highlighted the need and stimulated the research and development of new materials meeting the criteria of environmental regulations as well as satisfying the requirements of the industry.
Among the alternatives, NCs comprised of III-V semiconductors stand out not only due to their relatively benign nature but also due to expected higher robustness because of the high covalency of the crystalline structure, a broad range of bandgaps spanning from ultraviolet to deep-infrared regions, efficient light absorption, and high mobility of charge carriers. Although the first syntheses of such NCs were reported at around the same time as II-VI and IV-VI ones, the state-of-the-art III-V nanomaterials are still noticeably inferior to their Cd- and Pb-chalcogenide-based counterparts. To tackle this issue, several problems need to be addressed, including broadening the range of synthetic precursors, designing new synthetic strategies, elucidation of NC formation mechanisms, and investigation of surface chemistry of NCs for controlling their shape, electronic and optical properties as well as tailoring III-V nanoparticles for applications.
The main objective of this Marie Skłodowska-Curie action is the implementation of an innovative approach to address several of these points by focusing on the design of synthetic procedures and the investigation of the new type of NCs – colloidal two-dimensional indium phosphide NCs – that may become new nontoxic material for LEDs and displays with superior efficiency, optical characteristics, and simple device structure.