Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831, USA.
Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
Faraday Discuss. 2017 Jul 1;199:393-403. doi: 10.1039/c6fd00251j. Epub 2017 Apr 21.
Two-dimensional materials, such as MXenes, are attractive candidates for energy storage and electrochemical actuators due to their high volume changes upon ion intercalation. Of special interest for boosting energy storage is the intercalation of multivalent ions such as Mg, which suffers from sluggish intercalation and transport kinetics due to its ion size. By combining traditional electrochemical characterization techniques with electrochemical dilatometry and contact resonance atomic force microscopy, the synergetic effects of the pre-intercalation of K ions are demonstrated to improve the charge storage of multivalent ions, as well as tune the mechanical and actuation properties of the TiC MXene. Our results have important implications for quantitatively understanding the charge storage processes in intercalation compounds and provide a new path for studying the mechanical evolution of energy storage materials.
二维材料，如 MXenes，由于其在离子嵌入时的高体积变化，是储能和电化学致动器的有吸引力的候选材料。特别有趣的是嵌入多价离子，如 Mg，由于其离子尺寸，其嵌入和传输动力学缓慢。通过将传统的电化学特性分析技术与电化学膨胀测量和接触共振原子力显微镜相结合，证明了 K 离子的预嵌入的协同效应可以改善多价离子的电荷存储，并调整 TiC MXene 的机械和致动性能。我们的结果对定量理解嵌入化合物中的电荷存储过程具有重要意义，并为研究储能材料的机械演化提供了一条新途径。
