Heinsol has thus far made important contributions to this end as we have developed novel approaches in colloidal quantum dot and nanocrystal devices with record low trap state densities by simultaneously passivating defects chemically (at the atomic level) and electronically (at the suprananocrystalline level). HEINSOL has demonstrated new ways of engineering nanocomposite structures comprising colloidal quantum dots by control of their energetic landscape and their density of states reaching record performance in infrared LEDs and solar cells. We have also shown that by combining 2D materials with colloidal quantum dots can reach to very high efficiency low cost tandem solar cells. On the other hand, we have further explored and synthesized novel semiconducting metal chalcogenide nanocrystals and quantum dots that are free of Pb and Cd and we envision to apply our developed engineering methodologies to those new materials towards environmentally friendly low cost solar cells. So far, we have further developed synthetic protocols for such environmentally free materials to enable low cost large scale production in the absence of needs for vacuum and high temperatures in order to increase also the manufacturing readiness level of this technology. We have indeed demonstrated solar cells based on AgBiS2 colloidal nanocrystals that are synthesized at room temperature in ambient conditions, with power conversion efficiency on par with that reported from such material produced previously using high temperature and vacuum-based hot injection techniques. By engineering such nanocrystals at the atomic level we have developed a material that exhibits the highest optical absorption among materials developed to date for solar cells. By doing so and by further optimizing surface passivation and device structure engineering we have reported the most efficient ultra-thin film solution processed solar cell [Nat. Photon. 16, 235–241 (2022)]. In the process of discovering new strategies of electronic doping of such materials we have realized the implications in adjacent application fields and have demonstrated the first solution processed Silicon compatible infrared laser opening new paths towards silicon photonics, low-cost LIDAR and optical communication applications [Nat. Photon. 15, 738–742 (2021)]. Last but not least, HEINSOL discovered new ways of controlling optoelectronic properties of quantum dots by engineering the energetic potential landscape at the supra-nanocrystalline level. This created a paradigm shift in designing and optimizing colloidal quantum dot optoelectronic devices. We have exploited those finding to produce colloidal quantum dot solar cells with open circuit voltage approaching the radiative limit and light emitting diodes with record high performance in the short-wave infrared. The latter allows the introduction of a new low-cost CMOS compatible LED technology with applications ranging from automotive safety to 3D imaging and biomedical and spectroscopy for health, environmental and product quality inspection [Nature Nanotech 14, 72–79 (2019)].
