Chae, Yoonjeong Kim, Seon Joon Cho, Soo-Yeon Choi, Junghoon Maleski, Kathleen Lee, Byeong-Joo Jung, Hee-Tae Gogotsi, Yury Lee, Yonghee Ahn, Chi Won 2024-01-19T20:02:55Z 2024-01-19T20:02:55Z 2021-09-02 2019-05-07 2040-3364 https://pubs.kist.re.kr/handle/201004/120007 Two-dimensional (2D) transition metal carbides (MXenes) exhibit outstanding performances in many applications, such as energy storage, optoelectronics, and electrocatalysts. However, colloidal solutions of Ti3C2Tx MXene flakes deteriorate rapidly under ambient conditions due to the conversion of the titanium carbide to titanium dioxide. Here, we discuss the dominant factors influencing the rate of oxidation of Ti3C2Tx MXene flakes, and present guidelines for their storage with the aim of maintaining the intrinsic properties of the as-prepared material. The oxidation stability of the Ti3C2Tx flakes is dramatically improved in a system where water molecules and temperature were well-controlled. It was found that aqueous solutions of Ti3C2Tx MXene can be chemically stable for more than 39 weeks when the storage temperature (-80 degrees C) is sufficiently low to cease the oxidation processes. It was also found that if the Ti3C2Tx flakes are dispersed in ethanol, the degradation process can be significantly delayed even at 5 degrees C. Moreover, the oxidation stability of the Ti3C2Tx flakes is dramatically improved in both cases, even in the presence of oxygen-containing atmosphere. We demonstrate practical applications of our approach by employing Ti3C2Tx in a gas sensor showing that when oxidation is inhibited, the device can retain the original electrical properties after 5 weeks of storage. English ROYAL SOC CHEMISTRY TITANIUM CARBIDE MOLECULAR-DIFFUSION PERFORMANCE NANOSHEETS An investigation into the factors governing the oxidation of two-dimensional Ti3C2 MXene Article 10.1039/c9nr00084d 1 NANOSCALE, v.11, no.17, pp.8387 - 8393 NANOSCALE 11 17 8387 8393 scie scopus 000466774500031 2-s2.0-85064897852 Chemistry, Multidisciplinary Nanoscience & Nanotechnology Materials Science, Multidisciplinary Physics, Applied Chemistry Science & Technology - Other Topics Materials Science Physics Article TITANIUM CARBIDE MOLECULAR-DIFFUSION PERFORMANCE NANOSHEETS MXene oxidation stability low temperature