Galvanic Replacement Reactions in Metal Oxide Nanocrystals
Galvanic Replacement Reactions in Metal Oxide Nanocrystals
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DOI：
10.1126/science.1234751
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发表时间：
2013-05-24
期刊：
影响因子：
56.9
通讯作者：
Hyeon, Taeghwan
中科院分区：
文献类型：
--
作者：
Oh, Myoung Hwan;Yu, Taekyung;Hyeon, Taeghwan
电偶取代反应为制备具有可控孔结构和组成的中空纳米结构提供了一种简单而通用的方法。然而，这些反应以前仅限于金属纳米结构的化学转化。我们还展示了金属氧化物纳米晶中的电偶取代反应。当氧化锰(Mn3O4)纳米晶与高氯酸铁(II)反应时，得到了中空的盒状纳米晶Mn3O4/γ-Fe2O3(“纳米盒”)。这些纳米盒子最终转变成了中空的笼状纳米晶--伽马-铁氧化物(“纳米笼”)。由于其组成的非均衡性和中空结构，这些纳米盒和纳米笼作为锂离子电池的负极材料表现出了良好的性能。对于其他金属对，包括Co3O4/SnO2和Mn3O4/SnO2，也证明了这种方法的普遍性。
Galvanic replacement reactions provide a simple and versatile route for producing hollow nanostructures with controllable pore structures and compositions. However, these reactions have previously been limited to the chemical transformation of metallic nanostructures. We demonstrated galvanic replacement reactions in metal oxide nanocrystats as well. When manganese oxide (Mn3O4) nanocrystals were reacted with iron(II) perchlorate, hollow box-shaped nanocrystats of Mn3O4/gamma-Fe2O3 ("nanoboxes") were produced. These nanoboxes ultimately transformed into hollow cagetike nanocrystats of gamma-Fe2O3 ("nanocages"). Because of their nonequihbrium compositions and hollow structures, these nanoboxes and nanocages exhibited good performance as anode materials for lithium ion batteries. The generality of this approach was demonstrated with other metal pairs, including Co3O4/SnO2 and Mn3O4/SnO2.