Strongly Modulated Exfoliation and Functionalization of MXenes with Rationally Designed Groups in Polymer: A Theoretical Study

作者：Qiye Guan, Hejin Yan, Yongqing Cai · 发表于：Chemistry of Materials · 年份：2022 · DOI：10.1021/acs.chemmater.2c01721 · 被引用次数：22 · 研究领域：MXene and MAX Phase Materials、2D Materials and Applications、Graphene research and applications

As emerging atomically ultrathin metal compounds, MXenes show great promise for catalytic and nanoelectronic applications due to their abundant surface terminations and high metallic conductivity. However, the tendency for interlayer adhesion and suffering from environmental disturbances significantly limit their endurance and efficiency. Herein, via conducting first-principles calculations, we explore surface passivation and exfoliation of MXenes via polymers, which have been experimentally proven to promote the performance. Nine kinds of monomers together with a typical MXene, Ti 3 C 2 T 2 (T = none, O, F, OH, F 0.5 O 0.5 ), as prototype composites are explored with respect to the adsorption and charge transfer associated with energetics and chemical redox, respectively. Our work shows that the naked Ti 3 C 2 MXene has strong ability to cleave and decompose the monomers. Surface-functionalized Ti 3 C 2 F 2, Ti 3 C 2 FO, and Ti 3 C 2 O 2 have a weak binding with monomers through only van der Waals force, whereas Ti 3 C 2 (OH) 2 also exhibits strengthened binding for some monomers. Specific functional groups in the monomer, such as the halogen, sulfur, and hydroxyl groups, or a relatively planar aromatic structure, largely contribute to the adsorption. We reveal that the functionalization through polymers would alter the carriers’ density via interfacial charge transfer in MXenes. While the naked Ti 3 C 2 and Ti 3 C 2 (OH) 2 donate electrons to the polymers, Ti 3 C 2 F 2, Ti ...