Size control of Au@Cu2O octahedra for excellent photocatalytic performance
Size control of Au@Cu2O octahedra for excellent photocatalytic performance
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Au@Cu2O八面体的尺寸控制具有优异的光催化性能
DOI：
10.1039/c1jm13672k
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发表时间：
2012-01-14
影响因子：
--
通讯作者：
Huang, Shaoming
中科院分区：
文献类型：
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作者：
Kong, Lina;Chen, Wei;Huang, Shaoming
单晶Cu2O多面体由于其固有的结构和特性、小尺寸和单分散性，在水介质中控制单晶Cu2O多面体是一个挑战，这是实现增强光催化活性的重要克服。在这里，我们使用以金纳米棒为种子的Cu2O的非均相成核而不是均相成核来实现随后的均匀晶体生长。我们获得了具有单晶外壳的近乎单分散的八面体Au@Cu2O纳米晶体，这与先前描述的五边形柱状结构不同。由于一个Au@Cu2O只能容纳一个Au纳米棒，我们推导了两个公式来方便地控制Cu2O壳层的尺寸。这些公式是通过调整相对量化的Au棒的数量来计算的。该公式还允许在使用给定数量的金种子时预测最终产品的大小。实验结果与计算值吻合较好。由于更大的比表面积和核壳相互作用中电荷分离的改善，使得五种不同尺寸的样品对MO的降解表现出优异的光催化活性。本文报道的合成策略为核壳纳米晶的单分散性和尺寸控制提供了线索，这对于开发性能更好的新型催化剂是科学和技术领域迫切需要的。
Due to its intrinsic structure and characteristics, small size and monodispersity, control of single-crystalline Cu2O polyhedra in aqueous media is a challenge, which is important to overcome to achieve enhanced photocatalytic activity. Here, we use heterogeneous nucleation, rather than homogeneous nucleation, of Cu2O with gold nanorods as seeds to realize subsequent uniform crystal growth. We obtained nearly monodisperse octahedral Au@Cu2O nanocrystals with single-crystalline shells, which are distinct from the pentagonal column-shaped structures previously described. Due to the fact that one Au@Cu2O holds only one Au nanorod, two formulas were deduced for convenient size control of the Cu2O shell. The formulas were calculated by adjusting the amount of Au rods that are relatively quantified. The formula also allows the size of the final product to be predicted when a given amount of gold seeds are employed. The experimental results agree well with the calculated data. The result of larger surface area and improved charge separation from core-shell interaction, made five samples of different sizes exhibit excellent photocatalytic activity toward MO degradation. The synthetic strategy reported here provides a clue to monodispersity and size control of core-shell nanocrystals, which is useful in developing new catalysts with better performance that are urgently needed in the fields of both science and technology.