The control of nanostructured ZnO materials is essential for the development of smart and functional nanoscale devices. Using controlled hydrothermal growth conditions, Co and Gd co-doped ZnO hexagonal nanocrystals were synthesized at low temperature (70°C). The role of hexamethylenetetramine (HMTA) in engineering pure and doped ZnO morphology was examined. The results indicated that the hexagonal plates are transformed to hexagonal flower-like structure by changing the molar ratio of precursors: HMTA. The possible growth mechanism of the formation of hexagonal nanocrystals (hexagonal plates and nanoflower-like structure) is discussed. The magnetic properties exhibited enhanced ferromagnetism after incorporating Gd into ZnO matrix. An enhancement in saturation magnetization is discussed mainly in correlation with the strain effect. These doped ZnO nanostructures are expected to be driven mainly through improved the performance of spintronic devices.

中文翻译：

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水热法控制六方纳米晶Co和Gd共掺杂Zno的生长

纳米结构的ZnO材料的控制对于智能和功能纳米级设备的开发至关重要。利用受控的水热生长条件，在低温（70℃）下合成了Co和Gd共掺杂的ZnO六角形纳米晶体。检验了六亚甲基四胺（HMTA）在工程纯的和掺杂的ZnO形态中的作用。结果表明，通过改变前驱体：HMTA的摩尔比，六角形板转变为六角形的花状结构。讨论了可能形成六角形纳米晶体（六角形板和纳米花状结构）的生长机理。将Gd掺入ZnO基体后，磁性表现出增强的铁磁性。主要与应变效应相关地讨论了饱和磁化强度的提高。