Publications de Julia Anna Wiktor

Oxygen Evolution at the BiVO4-Water Interface: Mechanism of the Water Dehydrogenation Reaction

Alfredo Pasquarello, Julia Anna Wiktor, Sai Lyu

We study the water dehydrogenation reaction at the BiVO4(010)-water interface by combining nudged-elastic-band calculations and electronic structure calculations at the hybrid functional level. We investigate the pathway and the kinetic barrier for the adi ...

AMER CHEMICAL SOC2022

Small Electron Polarons in CsPbBr3: Competition between Electron Localization and Delocalization

Alfredo Pasquarello, Stefano Falletta, Julia Anna Wiktor

We study the nature of excess electrons in CsPbBr3 and identify several single and double polaronic states. We emphasize the importance of proper inclusion of the self-interaction corrections for the stability of small electron polarons in this material. W ...

AMER CHEMICAL SOC2020

Finite-size corrections of defect energy levels involving ionic polarization

Alfredo Pasquarello, Stefano Falletta, Julia Anna Wiktor

We develop a scheme for finite-size corrections of vertical transition energies and single-particle energy levels involving defect states with built-in ionic polarization in supercell calculations. The method accounts on an equal footing for the screening ...

2020

Low-Frequency Dielectric Response of Tetragonal Perovskite CH3NH3PbI3

Alfredo Pasquarello, Julia Anna Wiktor, Ethan Alexandre Berger

The dielectric properties of tetragonal hybrid perovskite CH3NH3PbI3 are studied through molecular dynamics at a temperature of 300 K in the presence of a finite electric field. The high-frequency dielectric constant epsilon(infinity), is found to be 4.5 a ...

AMER CHEMICAL SOC2020

Nonempirical hybrid functionals for band gaps of inorganic metal-halide perovskites

Alfredo Pasquarello, Wei Chen, Julia Anna Wiktor, Thomas Bischoff

Nonempirical hybrid functionals are investigated for band-gap predictions of inorganic metal-halide perovskites belonging to the class CsBX3, with B = Ge, Sn, Pb and X = Cl, Br, I. We consider both global and range-separated hybrid functionals and determin ...

2019

Electron and Hole Polarons at the BiVO4-Water Interface

Alfredo Pasquarello, Julia Anna Wiktor

We determine the transition levels of electron and hole polarons at the BiVO4-water interface through thermodynamic integration within a hybrid functional scheme, thereby accounting for the liquid nature of the water component. The electron polaron is foun ...

2019

pH-Dependent Surface Chemistry from First Principles: Application to the BiVO4(010)-Water Interface

Alfredo Pasquarello, Francesco Ambrosio, Julia Anna Wiktor

2018

Role of Polarons in Water Splitting: The Case of BiVO4

Alfredo Pasquarello, Francesco Ambrosio, Julia Anna Wiktor

2018

Surface Polarons Reducing Overpotentials in the Oxygen Evolution Reaction

Alfredo Pasquarello, Francesco Ambrosio, Julia Anna Wiktor, Patrick Gono

2018

Mechanism suppressing charge recombination at iodine defects in CH3NH3PbI3 by polaron formation

Alfredo Pasquarello, Francesco Ambrosio, Julia Anna Wiktor

Metal-halide perovskites exhibit high efficiencies in photovoltaic applications and low recombination rates, despite the high concentrations of intrinsic defects. We here study the hole trapping at the negative iodine interstitial, which corresponds to the ...

Royal Society of Chemistry2018