New insights into the electronic structures and optical properties in the orthorhombic perovskite MAPbI3: a mixture of Pb and Ge/Sn. (12th September 2017)

• Record Type: Journal Article
• Authors: Chang, Junli; Wang, Guangzhao; Huang, Yuhong; Luo, Xukai; Chen, Hong
• Is Part Of: New journal of chemistry. Volume 41:Number 19(2017)
• Page Start: 11413
• Page End: 11421
• Publication Date: 2017-09-12
• Subjects: Chemistry -- Periodicals; Chimie -- Périodiques; 540
• DOI: 10.1039/c7nj01442b
• Languages: English
• ISSNs: 1144-0546

Abstract

Abstract : The photovoltaic performance of the organic–inorganic hybrid perovskite MAPbI3 can be significantly improved by the substitution of Ge/Sn for Pb. Abstract : As a new type of promising photovoltaic material, organic–inorganic hybrid perovskites (OIHPs) have attracted particular attention owing to their rapid increase in power conversion efficiency (PCE). It is quite remarkable that within several years PCEs have speedily exceeded the value of 20% from the original 3.8% in 2009. Nevertheless, the existence of heavy metal lead in the prototype perovskite MAPbI3 poses a great threat to human health and the living environment. To explore potential alternatives, we choose the congener elements of Ge and Sn as partial substituents for lead. By virtue of density functional theory calculations, the electronic structures and optical properties of Ge/Sn-doped perovskite compounds have been investigated involving GGA-PBE and DFT-SOC levels. The simulations indicate that the optical absorption coefficient is significantly enhanced due to the use of Ge/Sn dopants. Moreover, it is revealed that the absorption spectra shift towards the near infrared and even the middle infrared, and meanwhile, the band gap can be tuned by means of the Ge/Sn doping. Additionally, optical property analyses imply that the effect of spin–orbit coupling (SOC) plays a positive role for the application of OIHP materials in the photovoltaic field. These results shed a new light on a deep understanding of the nature of a range of functional materials constituted of OIHPs.