This study presents new findings related to the incorporation of MXene phases into ceramic. Aluminium oxide and synthesised Ti₃C₂ were utilised as starting materials. Knowing the tendency of MXenes to oxidation and degradation, particularly at higher temperatures, structural modifications were proposed. They consisted of creating the metallic layer on the Ti₃C₂, by sputtering the titanium or molybdenum. To prepare the composites, powder metallurgy and spark plasma sintering (SPS) techniques were adopted. In order to evaluate the effectiveness of the applied modifications, the emphasis of the research was placed on microstructural analysis. In addition, the mechanical properties of the obtained sinters were examined. Observations revealed significant changes in the MXenes degradation process, from porous areas with TiC particles (for unmodified Ti₃C₂), to in situ creation of graphitic carbon (in the case of Ti₃C₂-Ti/Mo). Moreover, the fracture changed from purely intergranular to cracking with high participation of transgranular mode, analogously. In addition, the results obtained showed an improvement in the mechanical properties for composites with Ti/Mo modifications (an increase of 10% and 15% in hardness and fracture toughness respectively, for specimens with 0.5 wt.% Ti₃C₂-Mo). For unmodified Ti₃C₂, enormously cracked areas with spatters emerged during tests, making the measurements impossible to perform.

A recent discovery of the unique biological properties of two-dimensional transition metal carbides (MXenes) resulted in intensive research on their application in various biotechnological areas, including polymeric nanocomposite systems. However, the true potential of MXene as an additive to bioactive natural porous composite structures has yet to be fully explored. Here, we report that the addition of 2D Ti₃C₂T_x MXene by reducing the porosity of the chitosan-hyaluronate matrix nanocomposite structures, stabilized by vitamin C, maintains their desired antibacterial properties. This was confirmed by micro computed tomography (micro-CT) visualization which enables insight into the porous structure of nanocomposites. It was also found that given large porosity of the nanocomposite a small amount of MXene (1–5 wt.%) was effective against gram-negative Escherichia coli, gram-positive Staphylococcus aureus, and Bacillus sp. bacteria in a hydrogel system. Such an approach unequivocally advances the future design approaches of modern wound healing dressing materials with the addition of MXenes.

This paper discusses the effects of the environment and temperature of the Ti₃C₂ (MXene) oxidation process. The MXene powders were annealed at temperatures of 1000, 1200, 1400, 1600, and 1800 °C in argon and vacuum using a Spark Plasma Sintering (SPS) furnace. The purpose of the applied annealing method was to determine the influence of a high heating rate on the MXene degradation scheme. Additionally, to determine the thermal stability of MXene during the sintering of SiC matrix composites, SiC–C–B–Ti₃C₂ powder mixtures were also annealed. The process parameters were as follows: Temperatures of 1400 and 1600 °C, and pressure of 30 MPa in a vacuum. Observations of the microstructure showed that, due to annealing of the SiC–C–B–Ti₃C₂ powder mixtures, porous particles are formed consisting of TiC, Ti₃C₂^sym, and amorphous carbon. The formation of porous particles is a transitional stage in the formation of disordered carbon structures.

This article presents new findings related to the problem of the introduction of MXene phases into the silicon carbide matrix. The addition of MXene phases, as shown by the latest research, can significantly improve the mechanical properties of silicon carbide, including fracture toughness. Low fracture toughness is one of the main disadvantages that significantly limit its use. As a part of the experiment, two series of composites were produced with the addition of 2D-Ti₃C₂T_x MXene and 2D-Ti₃C₂T_x surface-modified MXene with the use of the sol-gel method with a mixture of Y₂O₃/Al₂O₃ oxides. The composites were obtained with the powder metallurgy technique and sintered with the Spark Plasma Sintering method at 1900 °C. The effect adding MXene phases had on the mechanical properties and microstructure of the produced sinters was investigated. Moreover, the influence of the performed surface modification on changes in the properties of the produced composites was determined. The analysis of the obtained results showed that during sintering, the MXene phases oxidize with the formation of carbon flakes playing the role of reinforcement. The influence of the Y₂O₃/Al₂O₃ layer on the structure of carbon flakes and the higher quality of the interface was also demonstrated. This was reflected in the higher mechanical properties of composites with the addition of modified Ti₃C₂T_x. Composites with 1 wt.% addition of Ti₃C₂T_x M are characterized with a fracture toughness of 5 MPa × m^0.5, which is over 50% higher than in the case of the reference sample and over 15% higher than for the composite with 2.5 wt.% addition of Ti₃C₂T_x, which showed the highest fracture toughness in this series.

This article presents an attempt to determine the effect of the MXene phase addition and its decomposition during sintering with the use of the spark plasma sintering method on mechanical properties and residual stress of silicon carbide based composites. For this purpose, the unreinforced silicon carbide sinter and the silicon carbide composite with the addition of 2 wt.% of Ti₃C₂T_x were tested. The results showed a significant increase of fracture toughness and hardness for composite, respectively 36% and 13%. The numerical study involving this novel method of modelling shows the presence of a complex state of stress in the material, which is related to the anisotropic properties of graphitic carbon structures formed during sintering. An attempt to determine the actual values of residual stress in the tested materials using Raman spectroscopy was also made. These tests showed a good correlation with the constructed numerical model and confirmed the presence of a complex state of residual stress.