Chu Heying, Zhang Jingchuan, Zhao Pengsen, Li Yong, Liu Zhaoxia, Zhang Hongzhou
College of Mechanical and Electronic Engineering, Tarim University, Alar 843300, China.
College of Mechanical and Electronic Engineering, Wuhan Donghu University, Wuhan 430017, China.
Molecules. 2024 Dec 31;30(1):133. doi: 10.3390/molecules30010133.
Transition metal oxides are considered promising anode materials for high performance flexible electrodes due to their abundant reserves and excellent specific capacity. However, their inherent low conductivity, large volume effect, and poor cycling performance limit their applications. Herein, we report a novel "spontaneous complexation and exfoliation" strategy for the fabrication of flexible MnO NCs@rGO thin-film electrodes, which overcomes the aforementioned drawbacks and pushes the mechanical flexibility and lithium-ion (Li) storage performance to a higher level. The combination of large-area few-layer reduced graphene oxide (rGO) films and ultrafine MnO nanocrystals (MnO NCs) provides a high density of electrochemical active sites. Notably, the layer-by-layer embedded structure not only enables the MnO NCs@rGO electrodes to withstand various mechanical deformations but also produces a strong synergistic effect of enhanced reaction kinetics by providing an enlarged electrode/electrolyte contact area and reduced electron/ion transport resistance. The elaborately designed flexible MnO NCs@rGO anode provides a specific capacity of about 1220 mAh g over 1000 cycles, remarkable high-rate capacity (50.0 A g), and exceptional cycling stability. Finally, the assembled flexible lithium-ion full cells achieve zero capacity loss during repeated large-angle bending, demonstrating immense potential as a high-performance flexible energy storage device. This work provides valuable insights into unique structural designs for durable and ultra-fast lithium ion batteries.
过渡金属氧化物因其储量丰富和比容量优异，被认为是用于高性能柔性电极的有前景的负极材料。然而，其固有的低电导率、大体积效应和较差的循环性能限制了它们的应用。在此，我们报道了一种用于制备柔性MnO纳米晶@rGO薄膜电极的新型“自发络合与剥离”策略，该策略克服了上述缺点，并将机械柔韧性和锂离子存储性能提升到了更高水平。大面积少层还原氧化石墨烯（rGO）薄膜与超细MnO纳米晶（MnO NCs）的结合提供了高密度的电化学活性位点。值得注意的是，这种逐层嵌入结构不仅使MnO NCs@rGO电极能够承受各种机械变形，还通过提供更大的电极/电解质接触面积和降低电子/离子传输电阻，产生了增强反应动力学的强烈协同效应。精心设计的柔性MnO NCs@rGO负极在1000次循环中提供约1220 mAh g的比容量、显著的高倍率容量（50.0 A g）和出色的循环稳定性。最后，组装的柔性锂离子全电池在反复大角度弯曲过程中实现零容量损失，展现出作为高性能柔性储能器件的巨大潜力。这项工作为耐用和超快速锂离子电池的独特结构设计提供了有价值的见解。
