Abstract: 2D MXenes are known for their high electrical conductivity, hydrophilicity, functionalized surfaces and chemical and structural tunability. The MXene family has rapidly grown, with over 100 compositions synthesized to date. This rapid growth is driven by designer control of their composition and structures, including transition metals, non-metal sublattices, surface functional groups and atomic-layer configurations.
In this talk, I will present recent developments in the composition–structure–property relationships of MXenes. I will discuss ordered double-transition-metal MXenes, where two metals occupy specific atomic layers, and defect engineering through control of vacancies and substitutional defects at metal and non-metal sites. I will then present compositionally complex MXenes with up to nine transition metals and discuss how compositional complexity and entropy influence atomic ordering and properties.