The development of functional materials based on Earth-abundant, environmentally benign compositions is critical for ensuring their commercial viability and sustainable production. Here we present an investigation into the crystal chemistry and electrochemical properties of the muscovite clay KFe_2.75Si_3.25O₁₀(OH)₂. We first report a low-temperature hydrothermal reaction that allows for a significant degree of control over sample crystallinity, particle morphology, and cation distribution through the lattice. A complex sequence of stacking faults is identified and characterized using a combination of Mössbauer spectroscopy and total scattering neutron experiments. We then show the existence of a reversible electrochemical process using galvanostatic cycling with complementary cyclic voltammetry suggesting that the redox activity occurs primarily on the surface of the particles. We conclude by determining that the ability to (de)intercalate Li ions from the material is hindered by the strong negative charge on the transition metal silicate layers, which prevents the displacement of the interlayer K ions. This work calls attention to a hugely Earth-abundant family of minerals that possesses useful electrochemical properties that warrant further exploration.

中文翻译：

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铁白云母粘土的水热制备，晶体化学及氧化还原性质

基于丰富的地球环境友好成分的功能材料的开发对于确保其商业可行性和可持续生产至关重要。在这里，我们对白云母粘土KFe _2.75 Si _3.25 O ₁₀（OH）₂的晶体化学和电化学性质进行了研究。。我们首先报道了一种低温水热反应，该反应可对样品的结晶度，颗粒形态和阳离子通过晶格的分布进行很大程度的控制。利用莫斯鲍尔光谱法和总散射中子实验相结合，可以识别和表征一系列复杂的层错。然后，我们显示了使用恒电流循环与互补循环伏安法可逆的电化学过程的存在，这表明氧化还原活性主要发生在颗粒的表面。我们通过确定结论得出结论，过渡金属硅酸盐层上的强负电荷阻碍了锂离子从材料中脱嵌的能力，这阻止了层间K离子的移位。