Synergy of Black Phosphorus–Graphite–Polyaniline-Based Ternary Composites for Stable High Reversible Capacity Na-Ion Battery Anodes

• Published in: ACS applied materials & interfaces Vol. 11; no. 18; pp. 16656 - 16661
• Main Authors: Jin, Hongchang, Zhang, Taiming, Chuang, Chenghao, Lu, Ying-Rui, Chan, Ting-Shan, Du, Zhenzhen, Ji, Hengxing, Wan, Li-jun
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 08.05.2019
• Subjects: anodes; batteries; electrolytes; graphene; phosphorus; polymers; X-ray absorption spectroscopy; anode material; black phosphorus; sodium-ion batteries; phosphorus utilization; high reversible capacity
• ISSN: 1944-8244; 1944-8252; 1944-8252
• DOI: 10.1021/acsami.9b04088

In recent times, few-layer black phosphorus (BP) has attracted tremendous attention as a promising anode material for sodium-ion batteries due to its particular two-dimensional structure, good electron conductivity, and high theoretical capacity. The main disadvantages of BP-based materials are the lower practical specific capacity of the BP-based composite than expectation because of the low P atom utilization and the structural fracture due to the large volume expansion that occurs during sodiation/desodiation cycles. In this work, we report a ternary composite comprising BP, graphite, and polyaniline (BP-G/PANI) with a BP mass content of ∼65 wt %. The ternary composite provides an optimized ion pathway (electrolyte → PANI → BP-G → BP), which reduces the charge transfer resistance of the electrode. Also, further ex situ X-ray absorption spectroscopy measurements demonstrate that the presence of graphite in the BP-G composite allows a deep sodiation of BP and also leads to a higher sodiation/desodiation reversibility. In addition, the uniformly coated PANI also restricts the huge volume expansion of the BP electrode through discharge/charge processes, which promise the stable cycling performance of BP-G/PANI. Thus, our composite shows a high reversible gravimetric capacity of 1530 mAh gcompo. –1 at 0.25 A g–1 and a capacity retention of 520 mAh gcompo. –1 after 1000 cycles at a high current density of 4 A g–1.