In Situ Synthesis of Amorphous GeSe/CNT Composite via Defective‐carbon‐mediated Chemical Bonding for Ultrastable Na Ion Storage

• Published in: Chemistry, an Asian journal Vol. 18; no. 11; pp. e202300280 - n/a
• Main Authors: Lee, Geon‐Woo, Kim, Young Hwan, Choi, Song‐Gue, Choi, Hun Seok, Kim, Kwang‐Bum
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 01.06.2023
• Subjects: Amorphization; Anode. Amorphization; Bonding strength; Chemical bonds; Chemical synthesis; Chemistry; Defects; Electrode materials; Germanium selenide; Ion diffusion; Ion storage; Sodium; sodium ion battery; Germanium selenide; sodium ion battery; Anode. Amorphization
• ISSN: 1861-4728; 1861-471X; 1861-471X
• DOI: 10.1002/asia.202300280

Herein, we report the in‐situ synthesis of amorphous GeSe/CNT composite via defective‐carbon‐mediated chemical bonding for ultrastable Na‐ion storage. Structural defects in CNTs play a crucial role in the chemical bonding and bonding strength in GeSe/CNTs composites. Specifically, the bonding strength tends to increase with increasing defect concentrations of CNTs. Remarkably, the strong chemical bonding between GeSe and CNTs significantly weakens Ge−Se bonds and promotes amorphization of GeSe, thus facilitating a reversible conversion reaction and enhancing Na‐ion diffusion. Consequently, GeSe/CNTs composite exhibits outstanding cyclability of 87.9% even after 1000 cycles at 1 A g−1 and a high‐rate capability of 288.3 mA h g−1 at 10 A g−1. Our work presents a promising approach for the amorphization of electrode materials enabled by the defective‐carbon‐mediated strong chemical bonding for Li‐, Na‐, and K‐ion batteries. Structural defects in CNTs play a crucial role in the chemical bonding and bonding strength in GeSe/CNTs composites. Remarkably, the strong chemical bonding between GeSe and CNTs significantly weakens Ge−Se bonds and promotes amorphization of GeSe, thus facilitating a reversible conversion reaction and enhancing Na‐ion diffusion.