The role of the A-cations in the polymorphic stability and optoelectronic properties of lead-free ASnI(3) perovskites

Autor(es)

Ozorio, Mailde S. ^[1] ; Srikanth, Malladi ^[1] ; Besse, Rafael ^[2] ; Da Silva, Juarez L. F. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Sao Carlos Inst Chem, POB 780, BR-13560970 Sao Carlos, SP - Brazil

^[2] Univ Sao Paulo, Sao Carlos Inst Phys, POB 369, BR-13560970 Sao Carlos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Physical Chemistry Chemical Physics; v. 23, n. 3, p. 2286-2297, JAN 21 2021.
• Citações Web of Science: 0

Resumo

Tin-based ASnI(3) perovskites have been considered excellent candidates for lead-free perovskite solar cell applications; however, our atomistic understanding of the role of the A-cations, namely, CH3NH3 (methylammonium, MA), CH3PH3 (methylphosphonium, MP) and CH(NH2)(2) (formamidinium, FA), in the physical chemistry properties is far from satisfactory. For the first time, we report a density functional theory investigation of the MPSnI3 perovskite and non-perovskite phases as well as their comparison with the MASnI(3) and FASnI(3) phases, where we considered the role of the A-cation orientations in the structural stability of the ASnI(3) phases. The orthorhombic structure is the most stable studied phase, which agrees with experimentally reported phase-transition trends. In contrast with the cation size and the weak hydrogen bonding interactions, which contribute to structural cohesion between the inorganic framework and A-cation, the dipole-dipole interactions play an important role to drive the structures to the lowest energy configurations. From our analysis, the inorganic framework dominates the optical properties, band structure, and density of states around the band edges. Broader absorption and smaller band gap energies occur for the perovskite structures compared to the low-dimensional hexagonal/pseudo-hexagonal non-perovskites. (AU)

• Processo FAPESP: 17/11631-2 - CINE: desenvolvimento computacional de materiais utilizando simulações atomísticas, meso-escala, multi-física e inteligência artificial para aplicações energéticas
• Beneficiário: Juarez Lopes Ferreira da Silva
• Modalidade de apoio: Auxílio à Pesquisa - Programa Centros de Pesquisa em Engenharia
• Processo FAPESP: 18/16801-6 - Materiais baseados em perovskitas para fotovoltaicos: desde pontos quânticos até cristais
• Beneficiário: Srikanth Malladi
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 17/09077-7 - Estudo ab-initio das propriedades estruturais, eletrônicas, e ópticas de heteroestruturas de van der Waals
• Beneficiário: Rafael Besse
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 18/21401-7 - EMU concedido no processo 2017/11631-2: cluster computacional de alto desempenho - ENIAC
• Beneficiário: Juarez Lopes Ferreira da Silva
• Modalidade de apoio: Auxílio à Pesquisa - Programa Equipamentos Multiusuários