PhD Thesis Defense of Aliya Mukanova

When:
June 17, 2019 @ 2:00 pm – 4:00 pm
2019-06-17T14:00:00+06:00
2019-06-17T16:00:00+06:00
Where:
3e224

Nazarbayev University’s PhD Program in Science, Engineering and Technology is delighted to invite you to the PhD Thesis Defense:

Candidate: Aliya Mukanova, 4th-year PhD student

Thesis Title: “Design and Engineering of Advanced Si-based Thin Film Anode Materials for Li-ion Batteries”.

Lead Supervisor: Professor Zhumabay Bakenov, Dept. of Chemical and Materials Eng., School of Engineering, Nazarbayev University, Kazakhstan
Co-Supervisor: Dr. Arailym Nurpeissova, National Laboratory Astana, Nazarbayev University, Kazakhstan
External Supervisor:  Prof. Sung-Soo Kim, Graduate School of Energy Sciences and Technology, Chungnam National University, South Korea.

                                     Prof. Maksym Myronov, Department of Physics, Nano-Silicon Group, The University of Warwick, United Kingdom

Chair-Internal Examiner: Professor Luis R. Rojas-Solórzano,  Dept. of Mechanical and Aerospace Eng., School of Engineering, Nazarbayev University, Kazakhstan
Internal Examiner: Professor Boris Golman, Dept. of Chemical and Materials Eng., School of Engineering, Nazarbayev University, Kazakhstan
External Examiner: Professor Kyu Tae Lee, School of Chemical and Biological Engineering, Seoul National University, South Korea.

Abstract:
Lithium-ion batteries (LIBs) are the most powerful way of energy conversion and storage. Thin film batteries are the next generation of Li-ion battery technology with the thickness of tens µm and aimed to power a diverse range of microdevices. In order to increase the storage possibility of such batteries, new high capacity electrode materials should be developed. Silicon(Si)-based materials are the most promising anodes due to the highest theoretical capacity and a low potential. However, the current drawbacks of Si such as significant material degradation, low conductivity, and unstable solid electrolyte interphase layer impede its practical application and commercialization. In this doctoral thesis, the research has been performed in two main directions in order to improve the performance of current microbatteries.

The first direction is devoted to an investigation of novel monocrystalline silicon carbide thin film (3C-SiC) with a cubic lattice as an anode for LIBs. The advanced method of “single” particle measurement for studying the electrochemical properties of an individual microparticle provided the real data which allowed suggesting the mechanisms of lithiation/delithiation in 3C-SiC film. The use of the characterization techniques confirmed the high mechanical stability of the 3C-SiC crystal lattice after cycling. The obtained cutting-edge results demonstrated that 3C-SiC thin film exhibits the near-surface activity towards Li ions occurring through intercalation/deintercalation mechanism.

The second direction is aimed at the design of the three-dimensional (3D) amorphous Si (a-Si) thin film anode. The improvement of a-Si thin film anode was achieved through studying the effects of substrate surface condition, dopants incorporation, electrolyte additive and use of graphene (GF) underlayer. The designed 3D pure a-Si and a-Si/GF thin film anodes exhibited high electrochemical performance for several hundred cycles.

Date and time: June 17, 2019 (Monday) at 13:30, room 3e.224