Mahnaz Ghiasi

Research: X-ray Spectroscopic characterization of perovskite thin films

Solar photocatalysis is an environmentally friendly and economical process for wastewater treatment [1]. LaMnO₃ perovskite is a promising photocatalyst owing to its stability at high temperature, catalytic properties, non-toxicity and high resistance to dissolution in aqueous/organic solvents or acidic or basic media.
The aim of this research project is to extend the understanding of solar photocatalytic degradation of azo dyes at complex oxide heterostructures. LaMnO₃ will be used as a catalyst system. In addition to bulk LaMnO₃, the catalyst will be modified by growing a number of layers of LaMnO₃ on top of SrTiO₃. An important goal of the project is to determine the variation of the electronic structure and thus the photocatalytic activity of these heterostructures that can be significantly different from the pure LaMnO₃ perovskite. Considering LaMnO₃ as the starting compound, doping the A and B sites causes a charge imbalance that is neutralized by a change in the Mn valence state or the creation of a hole where the dopant sites in the solid are determined by the relative energies of the O 2p and Mn 3d bands. We are using ex-situ and in-situ X-ray absorption (XAS) [2] (Figure 1) and X-ray photoemission (XPS) techniques in order to track the effect of the dopant on the physical and catalytic properties of LaMnO₃ thin films.

[1] M. Ghiasi, A. Malekzadeh. Sep. Purif. Technol., 134 (2014) 12.
[2] M. Ghiasi, F. de Groot, et al., J. Phys. Chem. C 120 (2016) 8167.

CV:

October 2019-Present
Postdoctoral research fellow in the group of Prof. P. de Jongh, Materials Chemistry and Catalysis, Utrecht University, The Netherlands

2015-2019:
Postdoctoral research fellow in the group of Prof. F.M.F. de Groot, Materials Chemistry and Catalysis, Utrecht University, The Netherlands

July 2014-January 2015:
Guest researcher in the group of Prof. F.M.F. de Groot, Materials Chemistry and Catalysis, Utrecht University, The Netherlands

2010-2015:
PhD. in Inorganic Chemistry, Damghan University of Basic Sciences, Iran
Thesis title: Synthesis, characterization and catalytic properties of mono, bi and tri-metallic nano-oxides containing La, Ce, Sr, Mn, Ca and Co.

2008-2010:
MSc. in Inorganic Chemistry, Damghan University of Basic Sciences, Iran
Thesis title: Electrical conductivity and catalytic performance investigations over manganese, cerium or tungsten promoted Na2SO4/SiO2 catalysts for oxidative coupling of methane.

2003-2007:
B.Sc. in Applied Chemistry, Sharif University of Technology, Iran