Modification and Self-assembly of Layered Materials for Energy Storage Applications

Licentiate thesis, 2025

Layered materials are considered as promising candidates as cathode and anode materials for various energy storage applications, such as supercapacitors, lithium-ion batteries, sodium-ion batteries, etc., due to their unique structures and extraordinary properties. However, the further improvement of their performance for electrochemical energy storage devices is limited by issues, for example self-stacking of the layer materials, sluggish ions intercalation, and lack of the active sites on the surface.

This thesis explores several strategies including 1) self-assemble layered materials into 3-dimentional (3D) structures, 2) surface modification of layered materials, and 3) modulation of electrode structure to address the aforementioned issues with the aim to enhance the electrochemical performance of layered materials for supercapacitor and aluminum battery. The first part of the thesis explores ice-template methods for self-assembly of graphene and Ti3C2Tx MXene into a 3D structure and their effects on supercapacitor performance. The results from the first part indicated that the formed structure of as-prepared layered materials was widely distributed with outstanding integrity. The intrinsic structure makes it possible to exhibit superior specific gravimetric capacitance and rate capability when applied as electrode materials for supercapacitors. The second part of the thesis investigated the effect of surface modification via hydrogen plasma treatment on graphite materials as cathode for aluminum batteries. The galvanostatic charge–discharge measurements results demonstrated that hydrogen plasma-treated graphite delivers excellent performance, achieving a high specific capacity of 132.68 mAh/g at 50 mA/g and impressive rate capability with 83.94 mAh/g at 1000 mA/g. The third part of the thesis explored the influence of porous structure fabrication and nitrogen doping on graphene-based cathode for aluminum batteries. The electrochemical test results indicated a high reversible specific capacity for the porous nitrogen-doped graphene cathode (65.5 mAh/g at 0.1 A/g) and excellent rate performance (38.0 mAh/g at 5 A/g).

Herein, this thesis provides a systematic investigation of surface modification and self-assembly of layered materials, which provide alternative and efficient methods to improve the energy storage performance of layered materials.