Welcome

to my personal webpage!

to my personal webpage!

Over the past years, I have been forcing computers to explore the properties of new (and not so new) materials for energy related applications.

I am currently a Junior Professor (HDR) at the Université de Rennes in France.

  • Name: George (Yorgos) Volonakis
  • Office: 219, Second floor, Bât. 10B, Campus de Beaulieu
  • Email: yorgos.volonakis (at) univ-rennes.fr
  • Phone: +33 (0)2 23 23 56 82
  • Skype: volonakis
  • ORCID: 0000-0003-3047-2298

Latest News

Latest News

Research project: SURFIN

The ANR funded JCJC project SURFIN to explore surfaces and interfaces of new materials has been succesful.
Positions are now open.

ACS Materials Letters front cover

Bruno's latest work on the 'Fine Structure of Excitons in Vacancy-Ordered Halide Double Perovskites' was selected for the front cover of the January 2023 issue of ACS Materials Letters. Well done Bruno!

Research

Research

My research interests are within the broad and rapidly growing field of computational materials science. In particular, my work is application of numerical methods that are based on the solution of the quantum-mechanical equations (i.e. from first-principles or ab initio calculations) to explore materials for the next-generation energy applications. These findings aim to the accurate and predictive description of the most critical structural, electronic and optical properties of a variety of energy materials; the exploration of surface and interface phenomena that can be key parameters for their application in opto-electronic devices, and finally the design of new materials using state-of-the-art computational approaches.

Publications

Publications

2024 Publications

  • Intrinsic Limits of Charge Carrier Mobilities in Layered Halide Perovskites
    B Cucco, J Leveillee, VA Ha, J Even, M Kepenekian, F Giustino, G Volonakis.
    PRX Energy 3 (2), 023012
  • Polaronic Mass Enhancement and Polaronic Excitons in Metal Halide Perovskites
    M Baranowski, A Nowok, K Galkowski, M Dyksik, A Surrente, D Maude, M Zacharias, G Volonakis, S D Stranks, J Even, M Maczka, R Nicholas, P Plochocka.
    ACS Energy Letters 9, 2696-2702
  • A Crystalline 2D Fullerene‐Based Metal Halide Semiconductor for Efficient and Stable Ideal‐bandgap Perovskite Solar Cells
    W Shen, A Azmy, G Li, A Mishra, Z Syrgiannis, W Zheng, G Volonakis, M Kepenekian, J Even, L Wojtas, C Wang, L Huang, W Chen, S Zhou, J Zhou, G Zeng, D Pu, H Guan, G Fang, W Ke, I Spanopoulos.
    Advanced Energy Materials, 2400582

2023 Publications

  • Anharmonic electron-phonon coupling in ultrasoft and locally disordered perovskites
    M Zacharias, G Volonakis, F Giustino, J Even.
    npj Computational Materials 9, 153 (2023)
  • Anharmonic lattice dynamics via the special displacement method
    M Zacharias, G Volonakis, F Giustino, J Even.
    Physical Review B 108 (3), 035155
  • Surface and Optical Properties of Phase-Pure Silver Iodobismuthate Nanocrystals
    A Matuhina, GK Grandhi, A Bergonzoni, L Pedesseau, R Grisorio, S Annurakshita, H Ali-Loytty, R Varghese, K Lahtonen, G Volonakis, V Pecunia, G Bautista, J Even, P Vivo,
    Nanoscale 15, 14764-14773
  • Chemical Behavior and Local Structure of the Ruddlesden–Popper and Dion–Jacobson Alloyed Pb/Sn Bromide 2D Perovskites
    P Fu, MA Quintero, ES Vasileiadou, P Raval, C Welton, M Kepenekian, G Volonakis, J Even, Y Liu, C Malliakas, Y Yang, C Laing, VP Dravid, GNM Reddy, C Li, EH Sargent, MG Kanatzidis,
    Journal of the American Chemical Society 145 (29), 15997–16014
  • Novel 3D Cubic Topology in Hybrid Lead Halides with a Symmetric Aromatic Triammonium Exhibiting Water Stability
    ES Vasileiadou, IS Tajuddin, MC De Siena, VV Klepov, M Kepenekian, G Volonakis, J Even, L Wojtas, I Spanopoulos, X Zhou, AK Iyer, JL Fenton, WR Dichtel, MG Kanatzidis,
    Chemistry of Materials 35 (14), 5267–5280
  • Fine Structure of Excitons in Vacancy-Ordered Halide Double Perovskites
    B Cucco, C Katan, J Even, M Kepenekian, G Volonakis.
    ACS Materials Letters 5 (1), 52-59

2022 Publications

  • Silver–Bismuth Halide Double Salts for Lead‐Free Photovoltaics: Insights from Symmetry‐Based Modeling
    B Cucco, L Pedesseau, C Katan, J Even, M Kepenekian, G Volonakis.
    Solar RRL, 2200718
  • Short Aromatic Diammonium Ions Modulate Distortions in 2D Lead Bromide Perovskites for Tunable White-Light Emission
    P Fu, MA Quintero, C Welton, X Li, B Cucco, MC De Siena, J Even, George Volonakis, Mikaël Kepenekian, Runze Liu, Craig C Laing, Vladislav Klepov, Yukun Liu, Vinayak P Dravid, GN Manjunatha Reddy, Can Li, Mercouri G Kanatzidis.
    Chemistry of Materials 34 (21), 9685-9698
  • Ordered Mixed-Spacer 2D Bromide Perovskites and the Dual Role of 1, 2, 4-Triazolium Cation
    X Li, H Dong, G Volonakis, CC Stoumpos, J Even, C Katan, P Guo, Mercouri G Kanatzidis.
    Chemistry of Materials 34 (14), 6541-6552
  • Pb-free halide perovskites for solar cells, light-emitting diodes, and photocatalysts
    P Jiang, D Acharya, G Volonakis, M Zacharias, M Kepenekian, C Katan, J Even.
    APL Materials 10 (6), 060902
  • Origin of the high specific capacity in sodium manganese hexacyanomanganate
    K Hurlbutt, F Giustino, G Volonakis, M Pasta.
    Chemistry of Materials 34 (10), 4336-4343

2021 Publications

  • Electronic structure and stability of Cs2TiX6 and Cs2ZrX6 (X = Br, I) vacancy ordered double perovskites
    B Cucco, G Bouder, L Pedesseau, C Katan, J Even, M Kepenekian.
    Applied Physics Letters 119 (18), 181903
  • Quasiparticle Band Structure and Phonon-Induced Band Gap Renormalization of the Lead-Free Halide Double Perovskite Cs2InAgCl6
    VA Ha, G Volonakis, H Lee, M Zacharias, F Giustino.
    The Journal of Physical Chemistry C 125 (39), 21689-21700
  • Electronic structure and electron-transport properties of three metal hexacyanoferrates
    K Hurlbutt, F Giustino, M Pasta, G Volonakis.
    Chemistry of Materials 33 (17), 7067-7074
  • Phonon-limited mobility and electron–phonon coupling in lead-free halide double perovskites
    J Leveillee, G Volonakis, F Giustino.
    The Journal of Physical Chemistry Letters 12 (18), 4474-4482
  • Crystallographic, Optical, and Electronic Properties of the Cs2AgBi1–xInxBr6 Double Perovskite: Understanding the Fundamental Photovoltaic Efficiency
    L Schade, S Mahesh, G Volonakis, M Zacharias, B Wenger, F Schmidt, Sameer Vajjala Kesava, Dharmalingam Prabhakaran, Mojtaba Abdi-Jalebi, Markus Lenz, Feliciano Giustino, Giulia Longo, Paolo G Radaelli, Henry J Snaith.
    ACS Energy Letters 6 (3), 1073-1081
  • Ruddlesden–Popper‐Phase Hybrid Halide Perovskite/Small‐Molecule Organic Blend Memory Transistors
    M Gedda, E Yengel, H Faber, F Paulus, JA Kreß, MC Tang, S Zhang, Christina A Hacker, Prashant Kumar, Dipti R Naphade, Yana Vaynzof, George Volonakis, Feliciano Giustino, Thomas D Anthopoulos.
    Advanced Materials 33 (7), 2003137

A complete list of publications can be found on Google Scholar, or the detailed CV.

Open positions

Open positions

Now Closed: Two fully funded PhD student are now open. Starting dates November 2025 at the latest.
More info here and here.

Now Closed: A two-year (24-month) post-doctoral research position is now open. The selected candidate will work within the SURFIN ANR project "Surfaces and interfaces of novel perovskites and perovskitoids". Starting date January 2024 at the latest.
More info here.

Even if there are no open positions listed here, we are always looking for motivated candidates. Do not hesitate to contact me by email for positions and opportunities!

Contact

Contact

Postal Address

Institut des Sciences Chimiques de Rennes, Campus de Beaulieu, Bât. 10B, Equipe Chimie Théorique Inorganique (CTI), Case 1009, 35042, Rennes, France

Contact Number

+33 (0)2 23 23 56 82