Facile spray-drying process for the synthesis of hollow 3D MXene-encapsulated CoSnO3 nanoboxes with enhanced lithium storage properties.

Combining nanostructured materials with two-dimensional (2D) substrates has long been considered one of the most effective strategies for the production of superior-performance lithium-ion batteries (LIBs). However, the restacking of 2D materials and the volume expansion of the active material during cycling are issues that have yet to be fully addressed. Herein, we propose a facile spray-drying process to successfully encapsulate hollow CoSnO 3 nanoboxes in MXene nanosheets (MX/HCTO), forming three-dimensional (3D) MXene-based microspheres as an anode for LIBs. This 3D structure effectively inhibits the restacking of MXene nanosheets, resulting in a higher surface area and a greater number of active sites for Li+ storage. Encapsulating hollow CoSnO 3 nanoboxes in an MXene shell can also restrict the change in volume during cycling, thus inhibiting the structural collapse of the composite even after long-term cycling. With these advantages, the proposed 3D MX/HCTO composite exhibits a high specific capacity of 670 mA h g−1 at 5.0 A g−1 that is stable over 1000 cycles and a specific capacity of 288.6 mA h g−1 at a high current density of 20.0 A g−1. It's easy synthesis process and inexpensive precursors also ensure that it has the potential to be scaled up for mass production. [Display omitted] • Hollow CoSnO 3 encapsulated with MXene is synthesized by a spray drying process. • 3D structuring of MXene nanosheets effectively inhibits their restacking issue. • Encapsulating by MXene alleviate a huge volume change of CoSnO 3 during the cycling. • 3D MX/HCTO electrode showed excellent electrochemical Li-ion storage performance. • 3D MX/HCTO delivered a capacity of 670 mA h g−1 after 1000 cycles at 5.0 A g−1. [ABSTRACT FROM AUTHOR]