Fundamentals of MXene Synthesis Steps and Their Characterization Techniques: Morphological, Structural, and Electrochemical Properties

MXene phases, a rapidly expanding family of two‐dimensional transition metal carbides, nitrides, and carbonitrides, have grown to include more than 80 compositions since their discovery in 2011, owing to their exceptional electrical conductivity, tunable surface chemistry, and versatile functional properties that enable applications in energy storage, electromagnetic interference (EMI) shielding, biomedical technologies, and ultrasensitive sensing systems. Common acidic etching methods, coupled with highly sensitive process requirements, pose significant challenges limiting the scalable synthesis of MXene phases, particularly for mass production. This review presents a comprehensive evaluation of MXene synthesis, including acid etching and safer fluoride‐free acid etching methods. hydrofluoric acid (HF)‐etching, fluoride‐free, molten salt, electrochemical, and hydrothermal methods are extensively discussed in terms of their respective advantages, limitations and their effects on surface terminations. Following etching, the subsequent stages of intercalation, delamination, and postsynthesis treatments are addressed to highlight strategies for achieving high‐purity, stable, and single or few‐layer MXene sheets while preserving their structural integrity and high quality. In addition, common characterization techniques such as X‐ray diffraction (XRD), Scanning electron microscope (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), X‐ray photoelectron spectroscopy (XPS), and Fourier‐transform spectroscopy (FTIR) are discussed comprehensively, and electrochemical performance methods—including band structure, cyclic voltammetry (CV), galvanostatic charge/discharge (GCD), and electrochemical impedance spectroscopy (EIS)—are evaluated to correlate the morphological features of MXene phases with functional properties.