Synthesis Protocols of the Most Common Layered Carbide and Nitride MAX Phases

Abstract

MAX phases represent a large group of carbide‐ and nitride‐layered ternary compounds. Their general formula is Mn+1AXn, where n = 1–3, M is an early transition metal, A is an A‐group element, and X is either carbon or nitrogen. The MAX phases combine properties of metals (good electrical and thermal conductivity, machinability, low hardness, thermal shock resistance, and damage tolerance) with those of ceramics (high elastic moduli, temperature strength, and oxidation and corrosion resistance). Publications on MAX phases have increased considerably in recent years. A late development causing heightened interest in MAX phases is the possibility by which these can be selectively etched to MXenes by removal of the A‐group element. In view of optimizing properties for prospective applications, the synthesis protocols of some of the most common carbide and nitride MAX phases are reviewed. Characterization of their physical, mechanical, and corrosion/oxidation properties is also discussed. Recent developments have revealed the potential for further practical application and have led to accessible strategies to synthesize new MAX phases using the pressure‐less sintering, spark plasma sintering, or molten salt routes.

Formation Mechanism of High-Purity Ti2AlN Powders under Microwave Sintering

“…Finally, the sintered sample was subjected to pulverization and grinding. For comparison, two other raw material systems, 2Ti/1AlN and 2TiH 2 /1AlN [ 34 ], were also subjected to microwave sintering for 30 min at 1250 °C.…”

Strategies for Fabricating High‐Performance Electrochemical Energy‐Storage Devices by MXenes

“…[22] In a typical top-down synthesis procedure, for example, MXenes are prepared by selective removal of A layers from MAX phases. [23] In addition, the properties of the final products, including the content of defects, morphologies, and surface chemistries, are highly dependent on the experimental condition during the synthesis. [24]…”

The Role of Alkali Cation Intercalates on the Electrochemical Characteristics of Nb2CTX MXene for Energy Storage

“…MXenes, as a new class of two-dimensional (2D) materials, have received extensive attention due to their high conductivity, low optical absorption in the visible and infrared regions, hydrophilic surface, reversible surface redox reactions, and biocompatibility. [4][5][6] A first representative of the MXene family -2D Ti 3 C 2 -has been reported for the first time in 2011. [7] Since then, researchers have a keen interest in the synthesis and application of MXene.…”