论文标题
加密纳米棒中碱性离子二聚体的水诱导的形成
Water-induced formation of an alkali-ion dimer in cryptomelane nanorods
论文作者
论文摘要
事实证明，诸如$α-$ Mn $ _8 $ o $ $ o $ o $ o $ o $ o _ $ _8 $ _8 $ _8 $ _8 $ _（荷兰石）之类的隧道金属氧化物已被证明是高密度电池中电荷存储材料的令人信服的候选者。特别是，隧道可以支撑K $^+$离子的一维链（充当结构稳定的掺杂剂）和H $ _2 $ o分子，因为这些链受到强大的H键和静电相互作用的青睐。在这项工作中，我们研究了水分子在增强k $^+$ - 掺杂$α-$ mn $ _8 $ o $ o $ _ {16} $（cryptomelane）的稳定性方面的作用。合并的实验和理论分析表明，对于足够高的水和隧道离子，h $ _2 $ o将k $^+$离子从其自然结合位点取代。由于K $ _2^+$二聚体的形成，这种位移在能量上变得有利，从而修改了系统的化学计量电荷。这些发现对于将Cryptomelane视为Li $^+$/Na $^+$电池电极具有潜在的重要技术影响。我们的工作确立了水在改变隐杆菌的能量和结构特性中的功能作用，这一观察结果在先前的研究中经常被忽略。
Tunneled metal oxides such as $α-$Mn$_8$O$_{16}$ (hollandite) have proven to be compelling candidates for charge-storage materials in high-density batteries. In particular, the tunnels can support one-dimensional chains of K$^+$ ions (which act as structure-stabilizing dopants) and H$_2$O molecules, as these chains are favored by strong H-bonds and electrostatic interactions. In this work, we examine the role of water molecules in enhancing the stability of K$^+$-doped $α-$Mn$_8$O$_{16}$ (cryptomelane). The combined experimental and theoretical analyses show that for high enough concentrations of water and tunnel-ions, H$_2$O displaces K$^+$ ions from their natural binding sites. This displacement becomes energetically favorable due to the formation of K$_2^+$ dimers, thereby modifying the stoichiometric charge of the system. These findings have potentially significant technological implications for the consideration of cryptomelane as a Li$^+$/Na$^+$ battery electrode. Our work establishes the functional role of water in altering the energetics and structural properties of cryptomelane, an observation that has frequently been overlooked in previous studies.
