Qingqing Zhou, Vinay Maithani, Michael Prati, Stefano Ippolito, Megan A. Creighton, Yury Gogotsi, Sankha Mukherjee, Changhong Cao
Understanding the interfacial shear strength (ISS) of MXenes is essential for improving their mechanical reliability in applications where layered MXene structures experience repeated mechanical loads. The ISS governs the ability of adjacent layers to resist sliding or delamination. This study investigates the ISS and associated interfacial properties of Ti 3 C 2 T x -Ti 3 C 2 T x , Ti 3 C 2 T x -graphene, and Ti 3 C 2 T x -MoS 2 interfaces through a combination of friction force microscopy and density functional theory (DFT) calculations. Experimental results show that the Ti 3 C 2 T x -Ti 3 C 2 T x homo-interface demonstrates the strongest interactions, with the highest ISS, coefficient of friction, and adhesion energy, compared to the Ti 3 C 2 T x -graphene and Ti 3 C 2 T x -MoS 2 hetero-interfaces. Furthermore, DFT simulations based on experimentally relevant compositions and configurations highlighted the critical influence of surface terminations (including −H, −F, −OH, −O, and −Cl groups) on the interfacial behavior of heterostructures. These findings offer mechanistic insights into the role of surface chemistry in tuning friction and adhesion, providing a foundation for the design of robust MXene-based interfaces.