Ultrathin Sheets of Metal or Metal Sulfide from Molecularly Thin Sheets of Metal Thiolates in Solution
Ultrathin Sheets of Metal or Metal Sulfide from Molecularly Thin Sheets of Metal Thiolates in Solution
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DOI：
10.1021/cm5006949
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发表时间：
2014-06-10
影响因子：
8.6
通讯作者：
Prasad, Bhagavatula L. V.
中科院分区：
文献类型：
--
作者：
Busupalli, Balanagulu;Kummara, Sreenivas;Prasad, Bhagavatula L. V.
作为单分子厚的二维片材存在的材料有很大的需求，因为它们有望作为合成层状功能材料的前体。我们表明，金属硫醇盐，存在于纯状态的层状组件，可以分解成单独的分子片，简单地通过稀释在非极性有机溶剂，这些可以形成crosslinkedmetallic层热处理后基板上。我们建立了一个解决方案，使用的技术，包括X射线衍射，光散射，FTIR和TEM的组合，金属硫醇盐的解体的途径。我们的研究结果表明，钯-硫醇盐的层状结构被保存在甲苯中的浓度高达300%w/v和平均片间距离不变。有趣的是，即使将它们稀释至30%w/v，Pd-硫醇盐片的动力学仍然相关，尽管层状堆叠内的无序随着它们的相干长度的减小而增加。最后，在小于约5%w/v的稀释度下，可以获得这些结构的单独片层，其被分离并使用TEM直接观察。热处理的金属硫醇盐沉积在适当的基板上的金属或金属硫化物的形成与保留片状形态的dielectric膜。
Materials that exist as single molecule thick two-dimensional sheets are in great demand because they hold promise as precursors for synthesis of layered functional materials. We demonstrate that metal thiolates, that exist as lamellar assemblies in the neat state, can be disassembled into individual molecular sheets simply by dilution in apolar organic solvents and that these can form ultrathin metallic layers on substrates upon heat treatment. We establish the pathway to the disassembly of metal thiolates in solution using a combination of techniques, including X-ray diffraction, light scattering, FTIR, and TEM. Our results indicate that the lamellar structure of Pd-thiolates is preserved in toluene up to a concentration of 300% w/v and the average intersheet distance is unchanged. Interestingly, the dynamics of the Pd-thiolate sheets remain correlated even on diluting them up to 30% w/v, though the disorder within the lamellar stacks increases with a decrease in their coherence length. Finally, at dilutions less than about 5% w/v, individual sheets of these structures can be accessed that are isolated and directly observed using TEM. Heat treatment of the ultrathin films of metal thiolates deposited on appropriate substrates resulted in the formation of metal or metal sulfides with retention of sheetlike morphologies.