Two-dimensional van der Waals materials and their mixed low-dimensional hybrids for electrochemical energy applications

Compared with their three-dimensional counterparts, two-dimensional (2D) van der Waals (vdW) materials exhibit quantum confinement where charge carriers are spatially confined at the physical boundaries. Particularly, when mixing 2D materials with other low-dimensional (LD) materials, they exhibit enormous potential in electrochemical energy applications due to the reduced dimensionality and, more importantly, material integration synergy, resulting in controllability over mixture composition, layer stacking and arrangement, and interlayer coupling. In this article, the latest advancements in 2D vdW heterostructure and their mixed low-dimensional hybrids (MLDHs) are reviewed with an emphasis on innovations covering hybrid structure construction and electrochemical applications. Recent developments leveraging the 2D vdW platform to promote a mechanistic understanding of charge-transport dynamics at the electrified interface were highlighted. Fundamental insight into the synergistic effect of MLDH integration for advancing the development of electrochemical energy applications was discussed. The knowledge gained on how mixed-dimensional physics and chemistry influence the performance of metal ion batteries and electrocatalytic hydrogen evolution reaction will shed light on the design principle of the electrode materials and deepen the understanding of the process–structural–property–performance relationship of the vdW-based MLDHs. Graphical abstract