Skip to Main content Skip to Navigation
Theses

Computational modeling of photoactive materials and heterointerfaces for solar energy conversion

Abstract : In this thesis we have dealt with the computational modelling of materials and molecular systems that are used in dye-sensitized solar cells (DSSCs) and dye-sensitized photoelectrosynthetic cells (DSPECs). In particular, we have addressed the study of the elements composing these devices, i.e. dyes, semiconductors and interfaces, by means of computational chemistry techniques, paying special attention to the modelling of the dynamical, optical and electronic structure properties.The complexity of the systems and the physical processes involved requires the combined use of different theoretical methodologies, as detailed below. A perylene diimide (PDI) dye in solution has been investigated by combining Density Functional Theory based methods and classical molecular dynamics (MD) simulations. In particular, we focused on the excited state properties of its aggregates and on the simulation of its electronic absorption spectrum by taking into account vibronic effects. In this context, to have a reliable description of the potential energy surface we made use of a specifically parameterized Quantum-Mechanically Derived Force Field (QMD-FF). Regarding the semiconductors, we have studied different phases of WO₃, that is an n-type semiconductor, using methods based on the Green’s Functions in order to rationalize the role of the crystal lattice distortion on the band structure and on the electronic and optical properties. Lastly, we have studied a simplified, albeit realistic model, of a dye-sensitized NiO interface (C343@NiO(100)) by combining ab initio molecular dynamic (AIMD) and GW calculations to describe the role of thermal effects and of the environmental solvent molecules on the interfacial energy-level alignment.
Complete list of metadata

https://hal.univ-lorraine.fr/tel-03285124
Contributor : Thèses Ul <>
Submitted on : Tuesday, July 13, 2021 - 10:14:07 AM
Last modification on : Wednesday, July 14, 2021 - 3:27:33 AM

File

DDOC_T_2020_0284_SEGALINA.pdf
Files produced by the author(s)

Identifiers

  • HAL Id : tel-03285124, version 1

Citation

Alekos Segalina. Computational modeling of photoactive materials and heterointerfaces for solar energy conversion. Chemical Sciences. Université de Lorraine, 2020. English. ⟨NNT : 2020LORR0284⟩. ⟨tel-03285124⟩

Share

Metrics

Record views

40

Files downloads

42