Advancements in Ti3C2 MXene-Integrated Various Metal Hydrides for Hydrogen Energy Storage: A Review

The current world is increasingly focusing on renewable energy sources with strong emphasis on the economically viable use of renewable energy to reduce carbon emissions and safeguard human health. Solid-state hydrogen (H-2) storage materials offer a higher density compared to traditional gaseous and liquid storage methods. In this context, this review evaluates recent advancements in binary, ternary, and complex metal hydrides integrated with 2D Ti3C2 MXene for enhancing H-2 storage performance. This perspective highlights the progress made in H-2 storage through the development of active sites, created by interactions between multilayers, few-layers, and internal edge sites of Ti3C2 MXene with metal hydrides. Specifically, the selective incorporation of Ti3C2 MXene content has significantly contributed to improvements in the H-2 storage performance of various metal hydrides. Key benefits include low operating temperatures and enhanced H-2 storage capacity observed in Ti3C2 MXene/metal hydride composites. The versatility of titanium multiple valence states (Ti-0, Ti2+, Ti3+, and Ti4+) and Ti-C bonding in Ti3C2 plays a crucial role in optimizing the H-2 absorption and desorption processes. Based on these promising developments, we emphasize the potential of solid-state Ti3C2 MXene interfaces with various metal hydrides for fuel cell applications. Overall, 2D Ti3C2 MXenes represent a significant advancement in realizing efficient H-2 storage. Finally, we discuss the challenges and future directions for advancing 2D Ti3C2 MXenes toward commercial-scale H-2 storage solutions.