Dual-Type Carbon Confinement Strategy: Improving the Stability of CoTe2 Nanocrystals for Sodium-Ion Batteries with a Long Lifespan

• DOI: 10.1021/acsami.1c22486
• Publication Date: 2022-01-31T20:52:21Z
• Authors: Weiming Zhao; Wei Zhang; Yixi Lei; Lixiang Wang; Gaoyu Wang; Jiawei Wu; Wenbo Fan; Shaoming Huang
• Keywords: Carbon fibers; Sodium-ion battery

Sodium-ion batteries have great potential to become large-scale energy storage devices due their abundant and low-cost resources. However, the lack of anode cathode materials with both high density long-term cycling performance significantly affects commercial applications. In this work, uniform CoTe2 nanoparticles are generated from tellurization Co nanoparticles, which were coated polyvinylpyrrolidone in a three-dimensional (3D) porous carbon matrix (CoTe2@3DPNC). Finally, dual-type confinement structure is formed after during citric acid adopted as source inner scaffold. The hierarchical not only builds robust fast ion/electronic conductive 3D architecture but also mitigates volume expansion aggregation sodium insertion/extraction. Remarkably, CoTe2@3DPNC electrode displays reversible capacity (216.5 mAh g-1/627.9 cm-3 at 0.2 A g-1 200 cycles) outstanding (118.1 g-1/342.5 even 5.0 2500 cycles). Kinetics tests capacitance calculations clearly reveal battery-capacitive dual-model Na-storage mechanism. Furthermore, ex situ XRD/SEM/TEM demonstrate superior stability This work provides valuable strategy for rational structural design long-life electrodes advanced rechargeable batteries.