Reaction of titanium carbide with water

Hydrolysis of 2D Transition-Metal Carbides (MXenes) in Colloidal Solutions

“…Accordingly, to prevent fast and complete degradation, Ti-based carbide MXenes should be isolated from water in the first place, and not from oxygen, as deemed before; using deaerated water is less helpful in this respect than using aerated anhydrous organic solvent, such as iso-propyl alcohol or others . The final formation of TiO 2 in the process of MXene degradation in the presence of water is most likely a result of several processes, including formation of amphoteric amorphous titanium hydroxide due to hydrolysis of the MXenes with water first (similar to what has been proposed by Avgustinik et al for hydrolysis of bulk TiC), followed by its polymerization and conversion through several equilibrium steps and intermediates into TiO 2 particles. The fate of the MXene carbon atoms during these transformations still remains unclear.…”

“…28 On the other hand, many years ago Avgustinik et al studied slow and seemingly insignificant reactions of bulk TiC with water yielding small quantities of hydrocarbons and titania. 29 They mentioned that the hydrolysis of TiC is limited by the very surface, propagating no more than 10−15 nm into the carbide crystal structure. However, this length covers the entire thickness of both Ti 3 C 2 T x and Ti 2 CT x MXene monolayers, which are 0.82 and 0.57 nm, respectively, as estimated from their DFT optimized models (Figure 1).…”

“…In contrast, bulk interstitial (e.g., TiC) and covalent (e.g., SiC) carbides are known as “not hydrolyzed” and resistant to attack by water . On the other hand, many years ago Avgustinik et al studied slow and seemingly insignificant reactions of bulk TiC with water yielding small quantities of hydrocarbons and titania . They mentioned that the hydrolysis of TiC is limited by the very surface, propagating no more than 10–15 nm into the carbide crystal structure.…”

Dye adsorption and decomposition on two-dimensional titanium carbide in aqueous media

“…35 However, even without dissolved oxygen, delaminated Ti 3 C 2 T x single akes slowly react with water, in a fashion reminiscent of the reaction of the topmost 5-30 atomic layers in bulk TiC. 36 The conversion of Ti 3 C 2 T x layers into nanoscale TiO 2 may lead to an increase in the accessible surface area, which in turn could explain the continued drop in MB concentration in solution observed for prolonged holding times in the dark.…”

Understanding Chemistry of Two-Dimensional Transition Metal Carbides and Carbonitrides (MXenes) with Gas Analysis

“…The interactions of bulk carbides with water and aqueous acid or base solutions have received mixed representation in textbooks and papers. Although reports and common inorganic chemistry textbooks mention that titanium carbide is resistant to decomposition in water as well as aqueous acid and base solutions, − Avgustinik et al reported long ago the reaction between group IV metal carbides and water yielding hydrocarbons and hydroxides. Their results also showed that the extent of the attack by water is limited by 5–30 surface atomic layers of the carbide, which for a bulk material was properly deemed to be insignificant.…”