Selective Formation of Carbon-Coated, Metastable Amorphous ZnSnO3 Nanocubes Containing Mesopores for Use as High-Capacity Lithium-Ion Battery
Selective Formation of Carbon-Coated, Metastable Amorphous ZnSnO3 Nanocubes Containing Mesopores for Use as High-Capacity Lithium-Ion Battery
复制标题
DOI：
10.1002/smll.201400371
复制
发表时间：
2014-07-09
期刊：
影响因子：
13.3
通讯作者：
Lu, An-Hui
中科院分区：
文献类型：
--
作者：
Han, Fei;Li, Wen-Cui;Lu, An-Hui
以单分散的ZnSn（OH）（6）为活性前驱体，低温合成的聚多巴胺为碳前驱体，制备了尺寸约为37 nm的介孔和无定形ZnSnO 3纳米立方体，并在其表面包覆一层薄的多孔碳层。小的单个纳米立方体彼此交联以形成连续的导电框架和具有74 nm宽的大孔的互连多孔通道。由于其多特征的纳米结构，该材料表现出大大增强的可逆合金化/去合金化的整合（即，Li4.4Sn和LiZn转化为Sn和Zn）和转化（即，Sn和Zn氧化为ZnSnO 3）反应过程，具有高达100次循环的1060 mA h g（-1）的极高容量。在2和3 A g（-1）的速率下，也可以分别提供650和380 mA h g（-1）的高可逆容量。这种优异的电化学性能归因于ZnSnO 3的小粒径、良好的中孔性、无定形性质以及由互连碳层产生的连续导电框架。
Mesoporous and amorphous ZnSnO3 nanocubes of similar to 37 nm size coated with a thin porous carbon layer have been prepared using monodisperse ZnSn(OH)(6) as the active precursor and low-temperature synthesized polydopamine as the carbon precursor. The small single nanocubes cross-link with each other to form a continuous conductive framework and interconnected porous channels with macropores of 74 nm width. Because of its multi-featured nanostructure, this material exhibits greatly enhanced integration of reversible alloying/de-alloying (i.e., transformation of Li4.4Sn and LiZn to Sn and Zn) and conversion (i.e., oxidation of Sn and Zn to ZnSnO3) reaction processes with an extremely high capacity of 1060 mA h g(-1) for up to 100 cycles. A high reversible capacity of 650 and 380 mA h g(-1) can also be delivered at rates of 2 and 3 A g(-1), respectively. This excellent electrochemical performance is attributed to the small particle size, well-developed mesoporosity, the amorphous nature of the ZnSnO3 and the continuous conductive framework produced by the interconnected carbon layers.