Solvation structure design for stabilizing MXene in transition metal ion solutions
Jie Wang, Guohao Li, Guanshun Xie, Zhaohui Huang, Peng Zhang, Benhua Xu, Xiuqiang Xie, Nan Zhang
Abstract
Abstract Although MXene has attracted great interest in diverse fields, it is susceptible to oxidation in water (H 2 O) with transition metal ions such as Co 2+ , Fe 2+ , and Cu 2+ , which is pronounced at high temperatures. This impedes the preparation of MXene‐based composites and their functional applications. Here, this study revealed that Co 2+ increases the maximum and average atomic charge of H in H 2 O to improve the reactivity of H 2 O, which leads to the fact that Co 2+ catalyzes the oxidation of Ti 3 C 2 T x MXene. Furthermore, the addition of N,N‐dimethyl formamide (DMF) reduces the H 2 O activity and improves the oxidation stability of Ti 3 C 2 T x in the presence of Co 2+ via preferentially forming coordination bonds with Co 2+ . This strategy is also effective in enhancing the oxidation tolerance of Ti 3 C 2 T x to Fe 2+ in H 2 O. Moreover, it is feasible to enhance the oxidation stability of Ti 2 CT x MXene in H 2 O with the existence of Co 2+ . By virtue of these, the CoO/Ti 3 C 2 T x composite was successfully prepared without obvious Ti 3 C 2 T x oxidation, which is desirable to harness the advantages of Ti 3 C 2 T x as the complementary component for lithium‐ion batteries. This work provides a straightforward paradigm to enhance the oxidation resistance of MXene in H 2 O in the presence of transition metal ions and at high temperatures, which opens a new vista to use MXene for target applications.