Investigation of the electronic properties of the materials MQx (m = Cu, Ag, q = s, se, te, x = 0.0 - 2.0) through density functional theory calculations

• Grant number: 18/17460-8
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): October 01, 2018
• Effective date (End): September 30, 2020
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Physical-Chemistry
• Principal Investigator: Juarez Lopes Ferreira da Silva
• Grantee: Guilherme Kazuo Inui
• Host Institution: Instituto de Química de São Carlos (IQSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil
• Host Company: Universidade de São Paulo (USP). Instituto de Química de São Carlos (IQSC)
• Associated research grant: 17/11631-2 - Computational material science and chemistry, AP.PCPE

Abstract

Obtaining two-dimensional semiconductors with specific band properties gap, density of load carriers, etc., is a fundamental requirement for the development of several technological applications, such as photovoltaic devices. In this regard, chalcogenides materials with S, Se and Te in the composition, are very important, since the great variety of chemical compositions and crystalline structures in which are possible, materials with the physical and chemical properties of interest. Dichalcogenides de transitional metals have been extensively studied due to the interest in two-dimensional material. However, the potential of chalcogenides go far beyond the metal dicalcogenides transition-metals. For example, recent studies with chalcogenides based on metals from the11 (Cu and Ag), showed very interesting properties in these materials. The material Cu9 S5 was identified as a 2-p-type two-dimensional semiconductor, in contrast to semiconductors most widely used two-dimensional conductors, which are mostly n-type, and beyond Moreover, it has recently been observed that an Ag2S phase is a semiconductor with ductility close to metal at room temperature. Therefore, the exploration of new based on Cu and Ag offers an immense potential for the development of new semiconductors. To contribute to this end, this project of scientific initiation proposes to perform an ab initio theoretical investigation of the composition materials MQx (M = Cu, Ag; Q = S, Se, Te; x = 0.0 - 2.0). The structural, energy and electronic properties of various chemical compositions and crystalline structures of these materials will be obtained from of Density Functional Theory, in order to identify and characterize semiconductors with potential for application in solar cells.