Researchers Stefano Toso, Derek Dardzinski, Liberato Manna, and Noa Marom from the European Laboratory for Non-linear Spectroscopy and the Weizmann Institute of Science have developed a new computational tool called Ogre to accelerate the design and characterization of colloidal heterostructures. These are nanoparticles composed of two different materials connected at an interface, which can exhibit unique properties useful in various applications, including energy harvesting and storage.
The team’s work focuses on addressing a significant challenge in creating these heterostructures: assessing structural compatibility between complex materials with different lattice parameters and crystal structures. This compatibility is crucial for epitaxial growth, where one material grows on the crystalline substrate of another in a specific orientation. The researchers have enhanced Ogre to efficiently predict epitaxial interfaces between ionic or polar materials, which include most colloidal semiconductors.
Ogre’s improvements include pre-screening candidate models based on charge balance at the interface and using a classical potential for rapid energy evaluations. The parameters for these evaluations are automatically extracted from the input bulk structures, making the process more efficient. The researchers validated Ogre’s capabilities using CsPbBr3/Pb4S3Br2 heterostructures, demonstrating that the tool produces interface models consistent with both density functional theory and experimental data.
Furthermore, the team used Ogre to explain the templating effect of CsPbCl3 on the growth of lead sulfochlorides. They found that perovskite seeds induce the formation of Pb4S3Cl2 rather than Pb3S2Cl2 due to better epitaxial compatibility. By combining Ogre simulations with experimental data, the researchers were also able to unravel the structure and composition of the previously unsolved CsPbBr3/BixPbySz interface and assign structures to many other reported metal halide/oxide-based interfaces.
The practical applications of this research for the energy sector are significant. Colloidal heterostructures can be used to create more efficient solar cells, improved catalysts for energy conversion and storage, and advanced materials for energy harvesting and storage devices. By accelerating the design and characterization of these heterostructures, Ogre can help streamline the development of new materials for the energy industry.
The research was published in the journal Nature Communications.
This article is based on research available at arXiv.