Effects of chemical substitution on the structural and optical properties of alpha-Ag2-2xNixWO4 (0 <= x <= 0.08) solid solutions

Author(s)

Pereira, Wyllamanney da Silva ; Ferrer, Mateus Meneghetti ; Botelho, Gleice ; Gracia, Lourdes ; Nogueira, Icamira Costa ; Pinatti, Ivo Mateus ; Rosa, Ieda Lucia Viana ; La Porta, Felipe de Almeida ; Andres, Juan ; Longo, Elson

• Document type: Journal article
• Source: Physical Chemistry Chemical Physics; v. 18, n. 31, p. 21966-21975, AUG 31 2016.
• Web of Science Citations: 5

Abstract

In this work, we investigated the effects of chemical substitution on the structural, electronic, and optical properties of alpha-Ag2-2xNixWO4 (0 <= x <= 0.08) solid solutions prepared by a facile microwave-assisted hydrothermal method. The results showed that the increase of Ni concentration in alpha-Ag2WO4 microcrystals as a host matrix caused a morphological transformation and a shift of the electronic and optical properties. Based on first principles calculations and using Wulff's construction, particle shapes and their transformations in alpha-Ag2WO4 and alpha-Ag2-2xNixWO4 can be affected by controlling the ratios of surface energy values between the different facets. In addition, theoretical calculations revealed that Ni substitution in alpha-Ag2WO4 is more favorable in the Ag-2 and Ag-4 positions, in which the local coordination of Ag atoms corresponds to clusters with coordination numbers of seven and four, respectively. This behavior could be related to the degree of medium-range structural disorder in alpha-Ag2-2xNixWO4 crystals. The experimental results were correlated with theoretical simulations to achieve a deeper understanding of the relationship between morphology and properties. These results provide the basis for a rational design for the compositional modulation of structural and optical properties. (AU)

• FAPESP's process: 08/57872-1 - National Institute for Materials Science in Nanotechnology
• Grantee: Elson Longo da Silva
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 13/23995-8 - Synthesis of silver tungstate doped with Eu3+ and the study of their optical, photoluminescent and photocatalytic properties
• Grantee: Ivo Mateus Pinatti
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 13/07296-2 - CDMF - Center for the Development of Functional Materials
• Grantee: Elson Longo da Silva
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC
• FAPESP's process: 12/14468-1 - Development and theoretical-experimental interpretation of BaZrO3@ZnS system
• Grantee: Mateus Meneghetti Ferrer
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 15/11917-8 - Study of photoluminescent properties and photocatalytic of Ag4P2O7, Ag3-2xNixPO4 and Ag3-2xCuxPO4
• Grantee: Wyllamanney da Silva Sczancoski
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 14/04350-9 - Theoretical studies of BaZrO3 decorated with ZnS
• Grantee: Mateus Meneghetti Ferrer
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate