Ti3C2Tx MXene Polymer Composites for Anticorrosion: An Overview and Perspective

Abstract

As the most studied two-dimensional (2D) material from the MXene family, Ti₃C₂T_x has constantly gained interest from academia and industry. Ti₃C₂T_x MXene has the highest electrical conductivity (up to 24,000 S cm^-1) and one of the highest stiffness values with a Young's modulus of ∼ 334 GPa among water-dispersible conductive 2D materials. The negative surface charge of MXene helps to disperse it well in aqueous and other polar solvents. This solubility across a wide range of solvents, excellent interface interaction, tunable surface functionality, and stability with other organic/polymeric materials combined with the layered structure of Ti₃C₂T_x MXene make it a promising material for anticorrosion coatings. While there are many reviews on Ti₃C₂T_x MXene polymer composites for catalysis, flexible electronics, and energy storage, to our knowledge, no review has been published yet on MXenes' anticorrosion applications. In this brief report, we summarize the current progress and the development of Ti₃C₂T_x polymer composites for anticorrosion. We also provide an outlook and discussion on possible ways to improve the exploitation of Ti₃C₂T_x polymer composites as anticorrosive materials. Finally, we provide a perspective beyond Ti₃C₂T_x MXene composition for the development of future anticorrosion coatings.

Keywords: 2D materials; MAX phase; MXene; Ti3C2Tx; anticorrosion; coatings; polymer composites.

Figure 1

(a) Tafel plots of the anticorrosion properties of uncoated and coated samples after immersion in 3.5% NaCl for 96 h. The 1 wt %-coated sample shows the highest protection, indicated by the most positive shifting of potential value E_corr and the lowest corrosion current, I_corr. Here, potential (V vs SCE) refers to potential versus saturated calomel electrode, which serves as the reference electrode. (b) Schematic illustration of corrosion process without and with a Ti₃C₂T_x-contained epoxy coating. (c) Photographs of the samples before and after the salt spray test, where 1.0 wt % Ti₃C₂ offers the highest protection, in agreement with results in a. Reprinted with permission from ref (18) Copyright 2019 Elsevier.

Figure 2

Schematic illustration of synthesis and surface functionalization of Ti₃C₂T_x with APTES. Reprinted with permission from ref (36) Copyright 2020 Elsevier.

Figure 3

(a) Tafel plot of pure epoxy, l-M_0.5%, and f-M_0.5% after 4-week immersion in a 3.5% NaCl solution. f-M_0.5% shows the best anticorrosion performance, indicated by the most positive value. The potential (V vs SCE) refers to potential versus saturated calomel electrode, which serves as the reference electrode. (b) Schematic illustration of the corrosion protection process in pure epoxy, pristine Ti₃C₂T_x/epoxy, and APTES-functionalized/epoxy coatings. Reprinted with permission from ref (36) Copyright 2020 Elsevier.

Figure 4

Tafel plots of (a) uncoated Q235 steel, (b) pristine Ti₃C₂/WPU, and (c) WPU and functionalized Ti₃C₂@Si/WPU. The functionalized coated samples exhibit a positive shift value, indicating the highest corrosion protection. The potential (V vs SCE) refers to potential versus saturated calomel electrode, which serves as the reference electrode. Reprinted with permission from ref (41) Copyright 2021 Elsevier.

Figure 5

Mechanism of the corrosion protection for (a) pristine WPU, (b) Ti₃C₂T_x/WPU, and (c) functionalized Ti₃C₂T_x@Si/WPU. Reprinted with permission from ref (41) copyright 2021 Elsevier.

Figure 6

Schematic Illustration of the preparation of Ti₃C₂/PANI composites. (a) Preparation of Ti₃C₂ nanosheets. (b) Synthesis of Ti₃C₂/PANI composites (TPCs) with the mechanism of oxidative polymerization of aniline on Ti₃C₂. (c) Photograph of the samples before and after the salt spray test for 30 days. Reprinted with permission from ref (51) copyright 2021 Elsevier.

Figure 7

(a) Schematic illustration of the synthesis of Ti₃C₂T_x/graphene heterostructures with wrapping structures where MXene sheets are wrapped by graphene sheets. (b) Reduction of the corrosion polarization resistance R_p for all coatings. MG-EP shows the lowest reduction, while pure EP exhibits the highest loss of corrosion resistance. Reprinted with permission from ref (52) copyright 2020 Elsevier.