Synthesis of High Surface Area α-K y MnO 2 Nanoneedles Using Extract of Broccoli as Bioactive Reducing Agent and Application in Lithium Battery

Ahmed M Hashem (1) , Hanaa M Abuzeid (1) , Martin Winter (2) , Jie Li (3) , Christian Julien (4)

1 National Research Centre - NRC (EGYPT)
2 Institute of Physical Chemistry & MEET Battery Research Centre
3 School of Computer Science [Wuhan]
4 IMPMC - Institut de minéralogie, de physique des matériaux et de cosmochimie

With the aim to reduce the entire cost of lithium-ion batteries and to diminish the environmental impact, the extract of broccoli is used as a strong benign reducing agent for potassium permanganate to synthesize α-K y MnO 2 cathode material with pure nanostructured phase. Material purity is confirmed by X-ray powder diffraction and thermogravimetric analyses. Images of transmission electron microscopy show samples with a spider-net shape consisting of very fine interconnected nanoneedles. The nanostructure is characterized by crystallite of 4.4 nm in diameter and large surface area of 160.7 m 2 g −1. The material delivers an initial capacity of 211 mAh g −1 with high Coulombic efficiency of 99% and 82% capacity retention after 100 cycles. Thus, α-K y MnO 2 synthesized via a green process exhibits very promising electrochemical performance in terms of initial capacity, cycling stability and rate capability.

Mots clés: α-K y MnO 2; nanoneedles; lithium-ion batteries; green synthesis; cathode

Domaines: Chimie

Ahmed M Hashem, Hanaa M Abuzeid, Martin Winter, Jie Li, Christian Julien. Synthesis of High Surface Area α-K y MnO 2 Nanoneedles Using Extract of Broccoli as Bioactive Reducing Agent and Application in Lithium Battery. Materials, 2020, 13 (6), pp.1269. ⟨10.3390/ma13061269⟩. ⟨hal-02617509⟩