Investigation of electron transfer processes for energy conversion systems based on Ru(II)/Re(I)

• Grant number: 18/08038-0
• Support type: Scholarships abroad - Research Internship - Doctorate
• Effective date (Start): February 01, 2019
• Effective date (End): September 30, 2019
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Inorganic Chemistry
• Principal researcher: André Sarto Polo
• Grantee: Andressa Vidal Muller
• Supervisor abroad: Gerald Meyer
• Home Institution: Centro de Ciências Naturais e Humanas (CCNH). Universidade Federal do ABC (UFABC). Ministério da Educação (Brasil). Santo André , SP, Brazil
• Research place: University of North Carolina at Chapel Hill (UNC), United States
• Associated to the scholarship: 16/24020-9 - Evaluation of processes photoassisted by Ru(II) and Re(I) polypyridyl compounds, BP.DR

Abstract

Due to its versatility and unique combination of properties, Ru(II) and Re(I) polypyridyl compounds have been widely employed in sunlight conversion systems, such as Dye-Sensitized Solar Cells (DSSCs) or for photocatalytic CO2 reduction. The efficiency of these systems strongly depends on the molecular structure of the coordination compound and the relative rates of each of the several electron transfer reactions that are possible to occur in the energy conversion process. The goal of this internship is to investigate electron transfer processes that are associated with the energy conversion systems that are being evaluated in the main research project (2016/24020-9), i.e., solar-to-electrical or -chemical energy conversion photoassisted by Ru(II) and Re(I) polypyridyl coordination compounds, by using time-resolved techniques. The effect of changing the size and number of aromatic rings of the ancillary ligand of Ru(II) tris-heteroleptic compounds cis-[Ru(R2-phen)(dcbH2)(NCS)2], R-phen = 1,10-phenanthroline or derivative and dcbH2 = 2,2-bipyridine-4,4-dicarboxylic acid, on ground and excited state properties of the complexes and consequently in the kinetics of electron transfer processes that occur in DSSCs will be investigated. Time-resolved techniques will also be employed to investigate mononuclear Re(I) and binuclear Re(I)÷Ru(II) coordination compounds as photocatalysts for CO2 reduction aiming to understand the relationship between structure, photochemical and photophysical properties, photocatalytic activity and stability. The effect of immobilization of photocatalysts onto oxide surfaces on electron transfer processes will also be investigated with the aid of time-resolved techniques. Relationships between modifications on the structure of molecules, its properties and the rates and efficiency of electron transfer processes will be established. It is expected that this investigation provides useful guidelines for understanding the effects that govern these systems and for designing novel coordination compounds to achieve higher efficiency and stability. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

MUELLER, ANDRESSA V.; DE OLIVEIRA, KLEBER T.; MEYER, GERALD J.; POLO, ANDRE S. Inhibiting Charge Recombination in cis-Ru(NCS)(2) Diimine Sensitizers with Aromatic Substituents. ACS APPLIED MATERIALS & INTERFACES, v. 11, n. 46, p. 43223-43234, NOV 20 2019. Web of Science Citations: 0.