The main research topic of our group deals with the use of theoretical simulations to the study of Dye-Sensitized Solar cells (DSC), Perovskite Solar Cells and Organic Light-Emitting Diodes (OLED), examples of the “green revolution” which is driving the world economy towards a sustainable growth on a grand scale. A major difficulty in the theoretical and computational simulation of transition metal complexes and nano-structured materials resides is the inherent complexity of the systems under investigation. The complex interatomic interactions underlying these systems call for the use of accurate computational techniques, while the large dimensions of these systems substantially limit the accuracy of the computational tools which can be employed. Even computational tools showing a reasonable compromise between their accuracy and computational overhead, still have to tackle the inherent complexity of systems composed by several hundred (thousand) atoms, which usually show a large number of relevant geometrical configurations. The situation is even more severe if one considers properties related to excited states, such as those we are dealing with in DSC, OLED and materials for NLO. To solve this very challenging issue, we have over time set up an integrated computational strategy based on a combination of different codes and techniques rooted on Density Functional Theory (DFT), Time-Dependent DFT and GW methods incorporating relativistic effects.

Main recent applications are in the field of modeling lead-halide perovskites, simulating bulk, surfaces and nanostructures properties. Accurate electronic structure calculations give insight into defects, dynamic disorder and their impact on charge carrier dynamics. Interfaces with hole and electron selective materials (e.g. Spiro-OMeTAD and TiO2) are also actively investigated.

Representative recent publications (see for a full list):

1. Meggiolaro, D.; Mosconi, E.; De Angelis, F. "Formation of Surface Defects Dominates Ion Migration in Lead-Halide Perovskites" ACS Energy Lett., 2019, 4, 779-785.

2. Chen, B.; Li, T.; Dong, Q.; Mosconi, E.; Song, J.; Chen, Z.; Deng, Y.; Liu, Y.; Ducharme, S.; Gruverman, A.; De Angelis, F.; Huang, J. "Large electrostrictive response in lead halide perovskites" Nat. Mater., 2018, 17, 1020-1026.  

3. Meggiolaro, D.; Motti, S.; Mosconi, E.; Barker, A.; Ball, J.; Perini, C.A.R.; Deschler, F.; Petrozza, A.; De Angelis F. "Iodine chemistry determines the defect tolerance of lead-halide perovskites" Energy Environ. Sci., 2018, 11, 702-713.

4. De Angelis, F.; Petrozza, A. "Clues from defect photochemistry" Nat. Mater., 2018, 17, 377-384.

5. Ambrosio, F.; Wiktor, J.; De Angelis, F.; Pasquarello A. "Origin of Low Electron-Hole Recombination Rate in Metal Halide Perovskites" Energy Environ. Sci., 2018, 11, 101-105.

6. Cortecchia, D.; Neutzner, S.; Kandada, A. R. S.; Mosconi, E.; Meggiolaro, D.; De Angelis, F.; Soci, C.; Petrozza, A. "Broadband Emission in Two-Dimensional Hybrid Perovskites: The Role of Structural Deformation" J. Am. Chem. Soc., 2017, 139, 39-42.

7. Saliba, M.; Orlandi, S.; Matsui, T.; Aghazada, S.; Cavazzini, M.; Correa-Baena, J-P.; Gao, P.; Scopelliti, R.; Mosconi, E.; Dahmen, H., De Angelis, F.; Abate, A.; Hagfeldt, A.; Pozzi, G.; Grätzel, M.; Nazeeruddin, M.K. "A molecularly engineered hole-transporting material for efficient perovskite solar cells" Nat. Energy, 2016, 1, 15017.

8. Santiago-Gonzalez, B.; Monguzzi, A.; Azpiroz, J. M.; Prato, M.; Erratico, S.; Campione, S.; Lorenzi, R.; Pedrini, J.; Santambrogio, C.; Torrente, Y.; De Angelis, F.; Meinardi, F.; Brovelli, S. "Permanent excimer superstructures by supramolecular networking of metal quantum clusters" Science, 2016, 353, 571-575.