Electrochemical‐Reduction‐Assisted Assembly of a Polyoxometalate/Graphene Nanocomposite and Its Enhanced Lithium‐Storage Performance. Issue 33 (4th July 2013)

• Record Type: Journal Article
• Authors: Wang, Shan; Li, Haolong; Li, Shuang; Liu, Fang; Wu, Dongqing; Feng, Xinliang; Wu, Lixin
• Is Part Of: Chemistry. Volume 19:Issue 33(2013)
• Page Start: 10895
• Page End: 10902
• Publication Date: 2013-07-04
• Subjects: Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201300319
• Languages: English
• ISSNs: 0947-6539

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>Herein, we present an electrochemically assisted method for the reduction of graphene oxide (GO) and the assembly of polyoxometalate clusters on the reduced GO (rGO) nanosheets for the preparation of nanocomposites. In this method, the Keggin‐type H<sub>4</sub>SiW<sub>12</sub>O<sub>40</sub> (SiW<sub>12</sub>) is used as an electrocatalyst. During the reduction process, SiW<sub>12</sub> transfers the electrons from the electrode to GO, leading to a deep reduction of GO in which the content of oxygen‐containing groups is decreased to around 5 %. Meanwhile, the strong adsorption effect between the SiW<sub>12</sub> clusters and rGO nanosheets induces the spontaneous assembly of SiW<sub>12</sub> on rGO in a uniformly dispersed state, forming a porous, powder‐type nanocomposite. More importantly, the nanocomposite shows an enhanced capacity of 275 mAh g<sup>−1</sup> as a cathode active material for lithium storage, which is 1.7 times that of the pure SiW<sub>12</sub>. This enhancement is attributed to the synergistic effect of the conductive rGO support and the well‐dispersed state of the SiW<sub>12</sub> clusters, which facilitate the electron transfer and lithium‐ion diffusion, respectively. Considering the facile, mild, and environmentally benign features of this method, it is reasonable as a general route for the incorporation of more types of functional polyoxometalates onto graphene matrices; this may allow the creation of nanocomposites for versatile applications, for example, in the fields of catalysis, electronics, and energy storage.</p> </abstract>