Influence of the negative charge density of metalate nanosheets on their bottom-up synthesis
Influence of the negative charge density of metalate nanosheets on their bottom-up synthesis
复制标题
DOI：
10.1039/c8ce00642c
复制
发表时间：
2018-07-07
期刊：
影响因子：
3.1
通讯作者：
Ohya, Yutaka
中科院分区：
文献类型：
--
作者：
Ban, Takayuki;Wakita, Takahiro;Ohya, Yutaka
研究了金属化物纳米片的负电荷密度对其自下而上合成的影响。金属化物纳米片通常通过剥离层状金属化物来制备。对于每种金属盐，自下而上的合成仅产生一种类型的纳米片结构，尽管已知不同的层状结构。在这项工作中，我们比较了不同层状金属化物的晶体结构，结果表明每种金属化物形成了具有最低负电荷密度的金属化物纳米片。接下来，我们研究了金属离子的氧化态对自下而上合成金属化物纳米片的影响，因为金属化物片的负电荷密度可以根据金属离子的氧化态进行修改。对于锰酸盐纳米片的自下而上合成，最低的Mn氧化态可以在3到4之间，高达3.65。因此，它们的负电荷密度相对较小。此外，钴酸盐纳米片无法通过自下而上的过程获得。然而，层状钴酸盐的氧化导致大体积阳离子和水嵌入层间。这些结果表明，自下而上合成金属化物纳米片需要低负电荷密度。
The influence of the negative charge densities of metalate nanosheets on their bottom-up syntheses was examined. Metalate nanosheets are usually prepared by exfoliating layered metalates. For each metalate, the bottom-up synthesis yields only one type of nanosheet structure, although different layered structures are known. In this work, we compared the crystal structures of different layered metalates, and the results indicate that metalate nanosheets with the lowest negative charge density were formed for each metalate. Next, we examined the effect of the oxidation state of metal ions on the bottom-up synthesis of metalate nanosheets, because the negative charge density of the metalate sheets can be modified according to the oxidation state of the metal ion. For the bottom-up synthesis of manganate nanosheets, the lowest Mn oxidation state, which can be between 3 and 4, was as large as 3.65. Thus, their negative charge densities were relatively small. Additionally, cobaltate nanosheets could not be obtained via the bottom-up process; however, the oxidation of layered cobaltates led to the intercalation of bulky cations and water into the interlayer. These results suggest that low negative charge density is required for the bottom-up synthesis of metalate nanosheets.