Electrostatic Self-Assembly of TeO₂ Nanoparticles on Graphene Oxide/Carbon Nanotube Composite for High-Performance...

Tellurium dioxide (TeO₂) has garnered interest as a potential cathode material for high-energy aqueous zinc-ion batteries (AZIBs) due to its high theoretical capacity (1080 mAh g^-1). However, the low electronic conductivity of the TeO₂ and the dissolution of high-valence tellurium species (Te⁴⁺) during cycling constrain its performance. Herein, we rationally design a graphene oxide/carbon nanotubes (GO/CNTs)-supported TeO₂ composite (n-TeO₂/GO/CNTs) via poly(diallyldimethylammonium chloride) (PDDA) mediated electrostatic interaction. In this design, the nano-sized TeO₂ particles (n-TeO₂, 50-100 nm) shortens Zn²⁺ transport distances, and the GO/CNTs three-dimensional conductive network accelerates electron transport, synergistically improving the charge-transfer kinetics of TeO₂. Moreover, the PDDA-functionalized GO/CNTs surface also effectively suppresses the dissolution of Te⁴⁺ species by electrostatic interactions, reducing the loss of active material. Consequently, the n-TeO₂/GO/CNTs cathode exhibits a high reversible capacity (826.7 mAh g^-1 at 0.1 A g^-1) and outstanding cycling performance (324 mAh g^-1 after 500 cycles at 2 A g^-1).