2018/12/12 by Diego Guedes‐Sobrinho, Ivan Guilhon, Guedes-Sobrinho, Diego +5
Engineering · Materials Science · #Chalcogenide Semiconductor Thin Films #Chemical Physics (physics.chem-ph) #FOS: Physical sciences #Perovskite Materials and Applications #Solid-state spectroscopy and crystallography
paper · pdf · doi:10.48550/arxiv.1812.05150
openalex publication_date 2018/12/12 · openalex created_date 2022/08/01 · openalex updated_date 2026/07/28
The recent reaching of 20% of conversion efficiency by solar cells based on\nmetal hybrid perovskites (MHP), e.g., the methylammonium (MA) lead iodide,\nCH3NH3PbI3 (MAPbI3), has excited the scientific community devoted to the\nphotovoltaics materials. However, the toxicity of Pb is a hindrance for large\nscale commercial of MHP and motivates the search of another congener\neco-friendly metal. Here, we employed first-principles calculations via density\nfunctional theory combined with the generalized quasichemical approximation to\ninvestigate the structural, thermodynamic, and ordering properties of\nMAPb1-xSixI3, MAPb1-xGexI3, and MAPb1-xSnxI3 alloys as pseudo-cubic structures.\nThe inclusion of a smaller second metal, as Si and Ge, strongly affects the\nstructural properties, reducing the cavity volume occupied by the organic\ncation and limitating the free orientation under high temperature effects.\nUnstable and metaestable phases are observed at room temperature for\nMAPb1-xSixI3, whereas MAPb1-xGexI3 is energetically favored for Pb-rich in\nordered phases even at very low temperatures. Conversely, the high miscibility\nof Pb and Sn into MAPb1-xSnxI3 yields an alloy energetically favored as a\npseudo-cubic random alloy with tunable properties at room temperature.\n