Synthesis of Titanium-based Carbides and Nitrides for Electrochemical Energy Applications

Abstract

The global transition toward electrification, renewable energy integration, and data-intensive technologies has elevated the demand for advanced electrochemical systems capable of delivering high energy density, long-term stability, and efficient catalytic conversion. MXenes, a versatile family of two dimensional (2D) transition-metal carbides and nitrides, have emerged as promising candidates for such applications due to their exceptional electrical conductivity, tunable surface chemistry, and structural versatility. Specially, the performance and applicability of MXenes are strongly dictated by their synthesis pathways, precursor quality, and interfacial engineering, highlighting the need for systematic research on both carbide and nitride MXene systems. Chapter 2 focuses on titanium carbide MXenes, highlighting how controlled combinations of etchants and intercalants enable precise modulation of Ti3C2Tx flake dimensions throughout the synthesis process. This further demonstrates their integration with silicon-based anodes (Si, SiG) for lithium-ion batteries (LIB), showing how tailored MXene flake size, improved conductivity pathways, and optimized composite architectures significantly enhance capacity retention, and mechanical resilience under operating conditions. The dissertation further investigates titanium nitride MAXene structures for hydrogen production (Chapter 3). By optimizing nitride MAX synthesis, partially extracting the A-layer, and carbon nanoplating, the resulting carbon-coated MAXene provides a conductive and chemically durable platform for MoS2, enhancing active-site exposure and interfacial charge transport. The engineered heterostructure demonstrates improved HER activity and operational stability, revealing the strong catalytic promise of nitride-derived two-dimensional materials. An improved saturated salt solution etching (S3) route for titanium nitride MAX phase is presented, offering a substantial advancement over conventional molten-salt methods (Chapter 4). The resulting layered nitride MXenes form reliably under milder conditions and exhibit effective electromagnetic interference (EMI) shielding, demonstrating both their functional versatility and scalable potential. In summary, this dissertation establishes a framework for synthesizing and engineering titanium-based carbides and nitrides for electrochemical energy applications (Chapter 5). The integrated advances in battery anode design, HER catalysis, and nitride MXene synthesis provide both fundamental insights and practical methodologies that broaden the technological potential of MXenes in next-generation energy storage and conversion applications.