Centre for Energy Storage Research, Korea Institute of Science and Technology, 5, Hwarang-ro 14-gil, Seongbuk-gu, Seoul 02792, Republic of Korea.
Department of Materials Science and Engineering, Chosun University, 309 Pilmun-daero, Dong-gu, Gwangju 61452, Republic of Korea.
Nanoscale. 2018 Oct 18;10(40):18949-18960. doi: 10.1039/c8nr04555k.
MnFe2O4@PDA-coated MWCNT coaxial nanocables are successfully designed via a simple one-pot process by utilizing the adhesion property of polydopamine (PDA) with cations in aqueous solutions and employing a modified co-precipitation synthesis at a low temperature. The incorporation of the PDA coating layer on the MWCNT leads to the well-dispersed state of the MWCNTs in the aqueous solution due to the hydrophilic functional group of the PDA coating layer. In addition, the catechol-based functional group of the PDA coating layer effectively anchors the Mn and Fe ions from the aqueous solution before the co-precipitation process, eventually resulting in the preferential and homogeneous formation of MnFe2O4 nanoparticles on the MWCNT. The final MnFe2O4@PDA-coated MWCNT electrode exhibits excellent power characteristics such as a high rate capacity of around of 367 mA h g-1 at a 5C-rate condition (= 4585 mA g-1). Cycling tests reveal that the stable performance of the MnFe2O4@PDA-coated MWCNT electrode persists even after 350 cycles.
MnFe2O4@PDA 涂层 MWCNT 同轴纳米电缆通过一种简单的一锅法成功设计，利用聚多巴胺 (PDA) 在水溶液中与阳离子的粘附特性，并在低温下采用改良的共沉淀合成法。PDA 涂层在 MWCNT 上的掺入导致 MWCNT 在水溶液中处于良好分散状态，这是由于 PDA 涂层的亲水性官能团。此外，PDA 涂层的邻苯二酚基官能团在共沉淀过程之前有效地固定水溶液中的 Mn 和 Fe 离子，最终导致 MnFe2O4 纳米颗粒优先且均匀地在 MWCNT 上形成。最终的 MnFe2O4@PDA 涂层 MWCNT 电极表现出优异的功率特性，例如在 5C 速率条件（=4585 mA g-1）下约 367 mA h g-1 的高倍率容量。循环测试表明，即使经过 350 次循环，MnFe2O4@PDA 涂层 MWCNT 电极的稳定性能仍然存在。
