MXene-Based Aerogel Anchored with Antimony Single Atoms and Quantum Dots for High-Performance Potassium-Ion Batteries

Rationally electronic structure engineering of nanocomposite electrodes shows great promise for enhancing the electrochemical performance of rechargeable batteries. Herein, we report antimony single atoms and quantum dots (similar to 5 nm) codecorated Ti3C2Tx MXene-based aerogels (Sb SQ@MA) for highperformance potassium-ion batteries (PIBs). We found that the atomically dispersed Sb could modify the electronic structure of the Sb/Ti3C2Tx composite, improve the charge transfer kinetics, and enhance the potassium storage capability at the heterointerfaces. Additionally, the MXene-based aerogel with rich surface functional groups and defects provides abundant anchoring sites and endows the composite reinforced structural stability and highly efficient electron transfer. The high loading of Sb (similar to 60.3 wt %) with short ionic transport pathways is desired potassium reservoirs. These features synergistically enhance the rate and cycling performance of the Sb SQ@MA electrodes in PIBs. This work has demonstrated an enlightening technique to tailor the interface activity of heterostructured electrodes for electrochemical applications.

Automated summary

This study reports the use of Ti3C2Tx MXene-based aerogels modified with antimony single atoms for high-performance potassium-ion batteries. The atomically dispersed antimony can modify the electronic structure of the composite material, improve charge transfer kinetics, and enhance potassium storage capability. Additionally, the MXene-based aerogel with surface functional groups and defects provides excellent anchoring sites for antimony and improves structural stability and electron transfer efficiency. This research is of great importance for enhancing battery performance.