Determination of layered nickel hydroxide phases in materials disordered by stacking faults and interstratification
Determination of layered nickel hydroxide phases in materials disordered by stacking faults and interstratification
复制标题
层错和层间无序材料中层状氢氧化镍相的测定
DOI：
10.1039/d2ta07655a
复制
发表时间：
2023
影响因子：
11.9
通讯作者：
Lawson K
中科院分区：
文献类型：
--
作者：
Lawson K
在5℃至95℃的温度范围内，在1小时至1周的时间间隔内，研究了使用硝酸镍(II)和氢氧化钾溶液化学沉淀合成材料期间层状氢氧化镍(II)中堆垛层错和相层间无序的形成。通过加宽 00l 反射来识别堆积断层材料，而通过将 001 分裂成两条线来识别层间材料。与之前对这些材料的研究中提出的无序概念相反，这项工作通过振动光谱表明，α相和β相氢氧化物都存在于具有堆垛层错无序的材料中，而层状羟基盐也存在于被认为是层间化的材料中。制备 Ni3(OH)4(NO3)2 和 β-Ni(OH)2 的标准混合物，以研究特定振动带的强度是否与混合物中特定相的比例相关。 990 cm−1 和 1315 cm−1 处的 C2v 硝酸盐红外和拉曼谱带强度显示与相中掺入的层状羟基硝酸盐的量相关，理论上提供了一种确定混合组合物中组分的方法。由于层状氢氧化镍材料中的无序和相杂质影响其电活性稳定性和作为阴极材料的性能，因此这项工作在多个研究领域具有重要意义。
The formation of stacking faults and phase interstratification disorder in layered nickel(II) hydroxides during the chemical precipitation synthesis of materials using nickel(II) nitrate and potassium hydroxide solutions has been investigated in the temperature range of 5 °C to 95 °C and time intervals from 1 hour to 1 week. Stacking faulted materials were identified by broadening of the 00l reflections, while interstratified materials were identified through the splitting of the 001 into two lines. In contrast to the disorder concepts presented in previous studies of these materials, this work has shown through vibrational spectroscopy that both the alpha-phase and beta-phase hydroxides are present in materials described with stacking fault disorder, while layered hydroxysalts were additionally present in the materials considered to be interstratified. Standard mixtures of Ni3(OH)4(NO3)2 and β-Ni(OH)2 were prepared to investigate if the intensity of particular vibrational bands could be correlated with the proportion of the particular phases in mixtures. The intensities of the C2v nitrate infrared and Raman bands at 990 cm−1 and 1315 cm−1 were shown to correlate with the amount of layered hydroxynitrate incorporated in the phase, theoretically providing a method to determine the components in mixed compositions. Since disorder and phase impurities in layered nickel hydroxide materials affect both their electroactive stability and performance as cathode materials, this work has important implications in several research fields.