Engineering MXene surfaces and heterostructure interfaces for efficient heterogeneous catalysis

The surfaces and interfaces of catalysts dictate activity, selectivity, and stability in heterogeneous catalysis, yet achieving atomic-level control over charge density flow and reaction energetics across these regions remains challenging. MXenes, a rapidly expanding family of two-dimensional transition-metal carbides, nitrides, and carbonitrides, offer an exceptional platform to address these challenges owing to their compositional tunability, rich surface terminations, and the strong influence of these groups on their physicochemical properties. Surface engineering provides the foundation for tailoring MXene reactivity, where controlled regulation of terminations, heteroatom doping, defect generation, and morphology enables precise tuning of active sites, adsorption energies, and redox potentials. Nevertheless, optimizing a single material may not provide sufficient control over surface charge dynamics and reaction energetics. For this reason, interface engineering that couples MXenes with metals, semiconductors, or carbon materials has become essential, as such heterostructures create Fermi-level equilibration, built-in electric fields, and orbital hybridization that govern charge transport and reshape catalytic pathways. Together, these hierarchical design strategies transform MXenes from simple conductive supports into dynamic catalytic mediators that bridge electro-, photo-, and thermocatalysis. This review summarizes recent progress in MXene surface and interface engineering, elucidates how atomic configurations regulate charge dynamics and catalytic behavior, and outlines design principles for programmable, self-adaptive, and stable MXene catalysts toward sustainable heterogeneous catalysis.