Functional MXenes: Progress and Perspectives on Synthetic Strategies and Structure–Property Interplay for Next‐Generation Technologies

Abstract

MXenes are a class of 2D materials that include layered transition metal carbides, nitrides, and carbonitrides. Since their inception in 2011, they have garnered significant attention due to their diverse compositions, unique structures, and extraordinary properties, such as high specific surface areas and excellent electrical conductivity. This versatility has opened up immense potential in various fields, catalyzing a surge in MXene research and leading to note worthy advancements. This review offers an in‐depth overview of the evolution of MXenes over the past 5 years, with an emphasis on synthetic strategies, structure‐property relationships, and technological prospects. A classification scheme for MXene structures based on entropy is presented and an updated summary of the elemental constituents of the MXene family is provided, as documented in recent literature. Delving into the microscopic structure and synthesis routes, the intricate structure‐property relationships are explored at the nano/micro level that dictate the macroscopic applications of MXenes. Through an extensive review of the latest representative works, the utilization of MXenes in energy, environmental, electronic, and biomedical fields is showcased, offering a glimpse into the current technological bottlenecks, such asstability, scalability, and device integration. Moreover, potential pathways for advancing MXenes toward next‐generation technologies are highlighted.

CO2-Assisted Dehydrogenation of Propane by Atomically Dispersed Pt on MXenes

“…A series of MXenes models with the M 2 CO 2 formula were first constructed, where M refers to transition metal elements from groups IV (Ti, Zr, and Hf), V (V, Nb, and Ta), and VI (Cr, Mo, and W). Preparation of the MXene from its bulk MAX phase by etching and exfoliation typically results in MXene surfaces terminated with OH, F, and O groups. − ,− Recently, the pristine MXene without surface termination and the uniform O-terminated MXene surfaces have been successfully synthesized by substitution and elimination of surface terminal groups in inorganic molten salts . More importantly, microkinetic simulations suggested that more than 96% of the MXene surface was covered by O* groups due to facile CO 2 dissociation at the typical CO 2 -ODHP conditions (Table S6).…”

“…As a burgeoning class of two-dimensional (2D) materials, MXenes, − including transition metal carbides, nitrides, and carbonitrides, have shown to be highly effective for thermal catalysis. − The strong metal–support interaction (SMSI) − and diverse physio-chemical properties − make MXenes a robust platform in tailoring the morphology and electronic structures of the supported metals. Recently, MXene-supported Pt catalysts showed great potential in selective activation of the C–H bonds in alkanes. , Our group theoretically evaluated the potential application of MXene-supported metallic Pt for DDHP, and predicted that the Pt atomic layer supported on Mo 2 C and W 2 C would significantly improve propylene selectivity with comparable activity of propane conversion compared with the pure Pt(111) and Pt 3 Sn­(111) surfaces .…”

Multifunctional MXene/PEDOT:PSS-Based Phase Change Organohydrogels for Electromagnetic Interference Shielding and Medium-Low Temperature Infrared Stealth

“…As an excellent conductive material, Ti 3 C 2 T x (MXene) is a class of transition metal carbides/nitrides acquired by chemically etching the MAX phase. , MXene is considered to have better EMI shielding properties than conventional carbon-based materials owing to its superb electrical conductivity . At the same time, MXene has attracted wide attention for improving hydrogel conductivity and EMI shielding − due to its excellent hydrophilicity.…”

InVO4-Decorated Ti3C2 MXene for Efficient Photocatalytic Hydrogen Evolution

“…MXenes, discovered in 2011, display exceptional electrical conductivity, possess numerous active sites, and demonstrate chemical stability, making them promising two-dimensional materials for photocatalytic H 2 evolution. − The optimal utilization of MXene occurs when it is combined with semiconductor materials, resulting in enhanced charge transfer, suppression of carrier recombination, and consequently, improved photocatalytic performance. , Ti 3 C 2 , a renowned MXene, has been extensively studied for its ability to enhance photocatalytic H 2 evolution when combined with semiconductor photocatalysts . Ti 3 C 2 T x MXene and g-C 3 N 4 were created on polystyrene microbeads via electrostatic interaction, enhancing surface area, light absorption, and charge separation efficiency for excellent H 2 production .…”