Hyperporous Sponge Interconnected by Hierarchical Carbon Nanotubes as a High‐Performance Potassium‐Ion Battery Anode

• DOI: 10.1002/adma.201802074
• Publication Date: 2018-06-28T06:21:40Z
• Authors: Yunsong Wang; Zhipeng Wang; Yijun Chen; Hui Zhang; Muhammad Yousaf; Huaisheng Wu; Mingchu Zou; Anyuan Cao; Ray P. S. Han
• Keywords: Potassium-ion battery; Carbon fibers

Recently, commercial graphite and other carbon-based materials have shown promising properties as the anode for potassium-ion batteries. A fundamental problem related to those carbon electrodes, significant volume expansion, structural instability/collapsing caused by cyclic K-ion intercalation, remains unsolved severely limits further development applications of Here, a multiwalled hierarchical nanotube (HCNT) is reported address issue, reversible specific capacity 232 mAh g-1 , excellent rate capability, cycling stability 500 cycles are achieved. The key structure HCNTs consists an inner CNT with dense-stacked graphitic walls loose-stacked outer more disordered walls, individual interconnected into hyperporous bulk sponge huge macropore volume, high conductivity, tunable modulus. It discovered that dense-CNT serves robust skeleton, collectively, loose-CNT beneficial accommodation; meanwhile facilitates reaction kinetics offers stable surface capacitive behavior. has great potential in developing high-performance stable-structure electrodes next generation K metal-ion