We cordially invite you to participate in the IX International School-Conference of Young Scientists "Synthesis of Electrode Materials", which will take place at Skoltech on November 15-19, 2024. The registration deadline for the conference is July 31The conference theme will focus on experimental and theoretical aspects of electrode materials synthesis. Looking forward to see you!!


Origin of surface segregation in LiCoO2: A DFT+U study

A Boev, M Arsentev, S Fedotov, A Abakumov, D Aksyonov


To explain the behavior of commercially important doping elements, such as Mg, Al, Ti, V, Cr, Mn, Fe, and Ni, we performed a DFT study of their segregation at the (104) low-energy surface of LiCoO2. By careful control of local oxidation states and magnetic moments of surface atoms, we find their most stable configurations. We discover that all elements, except Al and Cr, are prone to segregation that is primarily driven by the surface energies' difference between the host and solute lattices, which is explained through crystal-field stabilization energies. An additional contribution to segregation is caused by the elastic energy penalty to the ionic size mismatch effect. Finally, we rationalize the available experimental results and provide several predictions of highly segregating and nonsegregating dopants.

segregation surf en diff    

On April 18th two of our bachelor students participated at the XVI International Scientific and Practical Conference Education and Science for Sustainable Development at section «Materials for energy production, conversion and storage». Marina Titarenko gave her talk on "Designing Fluorinated Electrolytes for Lithium-Metal Batteries". Nurlan Zhanabayev delivered a presentation titled "Computational Study of Point Defects in Metallic Lithium: Implementation of Solid-State Lithium-Ion Batteries".

Designing a 3D framework NaVOPO4 as a high-power, low-strain and long-life positive electrode material for Na-ion batteries

S Shraer, A Dembitskiy, I Trussov, A Komayko, D Aksyonov, N Luchinin, A Morozov, S Pollastri, G Aquilanti, S Ryazantsev, V Nikitina, A Abakumov, E Antipov, S Fedotov
In this paper, we offer a new NaVOPO4 polymorph adopting a KTiOPO4-type framework as a promising high-rate, low-strain and long-life positive electrode material for sodium-ion batteries. A carbon-coated NaVOPO4 demonstrates a specific capacity of ∼110 mAh g–1 at a C/10 rate at an average potential of ∼3.93 V vs. Na+/Na. The material maintains over 74 % of the initial capacity after 1000 cycles at a C/2 rate and around 87% at a 2C charge/discharge rate. Diffusion coefficients of 10–11 cm2 s–1 and DFT-calculated energy barriers of ∼0.15–0.35 eV indicate fast Na+ ion diffusion. Moreover, the operando XRD analysis coupled with DFT elucidates several phase transitions with a low volume variation of 2.4% in total, highlighting the reversibility and structural stability during Na+ de/insertion. Overall, NaVOPO4 exhibits attractive electrochemical performance and stability, making it a potential candidate for sodium-ion battery cathode materials.

Fermi Arcs Conductivity of Weyl and Dirac Semimetals

Sergey Savrasov

We invite you to participate in our Computational Materials Science seminar. Sergey Savrasov will give a talk about the condutivity of Weyl and Dirac semimetals. The meeting will be held on March 21st at 11 a.m. (Msk) in online format.

SKOLTECH CMS seminar poster Savrasov online A4