Understanding and Controlling the Photoluminescence Line Shapes of 2D Perovskites with Chiral Methylbenzylammonium-Based Cations

Autor(es)

Scalon, Lucas ; New, Arianne ; Ge, Ziyuan ; Mondal, Navendu ; Campos, Raquel Dantas ; Quarti, Claudio ; Beljonne, David ; Nogueira, Ana Flavia ; Bakulin, Artem A. ; Vaynzof, Yana

• Tipo de documento: Artigo Científico
• Fonte: CHEMISTRY OF MATERIALS; v. 36, n. 9, p. 12-pg., 2024-04-16.

Resumo

Chiral two-dimensional (2D) perovskites are a promising material class for the next generation of spintronic and chiroptical devices. Despite their promise, many aspects related to film formation and crystallization remain elusive. When chiral ammonium-based organic cations such as methylbenzyl-ammonium (MBA) are employed in the preparation of chiral 2D perovskites, their interaction with the halide species in the inorganic perovskite network often introduces substantial steric hindrance, leading to the formation of one-dimensional (1D) phase impurities within the 2D matrix. Here, we demonstrate that this 1D phase manifests itself in the photoluminescence (PL) spectra of the 2D perovskite film as an additional weakly emissive, thermally activated state with a self-trapped excitonic character, leading to an asymmetric PL response. We demonstrate that the strategic introduction of a methoxy (OMe) group on the para position of the MBA cations can mitigate the formation of the 1D phase. As a result, the emission band becomes narrower and more symmetric and the 2D perovskite film has a higher PL quantum yield at room temperature. Our findings elucidate the origins of asymmetry and broadband emission of MBA-based chiral 2D perovskites and highlight the indispensable role of molecular design in chiral organic cations in controlling phase purity and attaining the desired optical properties. (AU)

• Processo FAPESP: 20/04406-5 - Células solares de perovskita a partir de fontes baratas, fáceis e verdes: uma abordagem sinérgica da síntese de novos materiais transportadores de buracos e do uso de solventes mais ecológicos
• Beneficiário: Lucas Scalon
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto
• 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
• Processo FAPESP: 17/11986-5 - Geração e Armazenamento de Novas Energias: trazendo desenvolvimento tecnológico para o país
• Beneficiário: Ana Flávia Nogueira
• Modalidade de apoio: Auxílio à Pesquisa - Programa Centros de Pesquisa em Engenharia
• Processo FAPESP: 21/12104-1 - Revelando o papel dos espaçadores orgânicos quirais nas propriedades estruturais, fotofísicas e eletrônicas de estruturas de perovskita 2D e 3D/2D
• Beneficiário: Lucas Scalon
• Modalidade de apoio: Bolsas no Exterior - Estágio de Pesquisa - Doutorado Direto