MXenes as emerging 2D materials for hydrogen generation: advances and future prospects

Abstract

MXenes, a rapidly advancing class of two-dimensional materials, exhibit high electrical conductivity, large surface area, and tuneable surface terminations that enable efficient charge transport and catalytic activity for sustainable hydrogen evolution. This review examines MXene-based heterostructures for electrocatalytic, photocatalytic, and photoelectrochemical hydrogen production, with an emphasis on how compositional engineering, surface chemistry, and interfacial design synergistically govern catalytic performance. A central contribution of this work is the establishment of correlations between diverse synthesis methods and the resulting morphological and electronic features of MXenes. We further highlight the role of dimensional engineering, from conventional nanosheets to low-dimensional hybrids and hierarchical architectures, in improving charge transport, active site accessibility, and catalytic efficiency. Beyond performance enhancement, we discuss key degradation mechanisms, including oxidation, surface termination instability, and structural reconstruction, along with the mitigation strategies. Distinct from previous reviews, this work integrates experimental progress with computational advances, demonstrating how density functional theory, machine learning, and data-driven screening accelerate the discovery of durable, high-performance MXene-based hydrogen evolution catalysts. Finally, we identify persistent challenges and outline strategic directions for advancing MXenes toward next-generation hydrogen technologies.