Abstract:
As typical electrochemical energy storage devices, supercapacitors and lithium ion batteries have potential applications in a wide range of fields such as microelectronic devices, portable electronics, and large-scale electric vehicles, etc. Electrode materials are one of the key aspects determining the performance of these two devices (Jiang et al., 2012). In this talk, I will mainly discuss the electrochemical energy storage application of one kind of emerging electrode architecture, that is, metal oxide-based nanostructure arrays grown directly on current collector substrates (Jiang et al., 2011). The direct growth of nanostructures on current collector represents a popular way to fabricate thin-film electrodes, which not only ensures good charge transport, but also provides sufficient structural interspaces for buffering volume expansion of the electrode materials. When combined with using flexible current collector, such thin-film electrode also has greater durability to shape deformation, giving better mechanical flexibility. By pairing appropriate electrode materials, ordered core-shell and hierarchical hybrid nanostructures can be rationally designed, which leads to synergistic improvement in terms of electrical/ionic conductivity, electrochemical stability and structural integration (Liu et al., 2011). Hybrid electrode materials with high capacitance/capacity, long cycle life and exceptional rate capability can thus be obtained; the related performance enhancement mechanism will also be discussed in detail. In the end, I will further show that these binder-free nanoarray electrodes have enabled high-performance thin-film/flexible energy storage devices (Zhou et al., 2013).
References
Jiang J, Li YY, Liu JP, 2012. Recent Advances in Metal Oxide-based Electrode Architecture Design for Electrochemical Energy Storage. Advanced Materials 24: 5166-5180.
Jiang J, Liu JP, 2011. Building One-Dimensional Oxide Nanostructure Arrays on Conductive Metal Substrates for Lithium-Ion Battery Anodes. Nanoscale 3: 45-58.
Liu JP, Jiang J, Cheng CW, 2011. Co3O4 Nanowire@MnO2 Ultrathin Nanosheet Core/Shell Arrays: A New Class of High-Performance Pseudocapacitive Materials. Advanced Materials 23: 2076-2081.
Zhou C, Zhang YW, Li YY, Liu JP, 2013. Construction of High-Capacitance 3D CoO@Polypyrrole Nanowire Array Electrode for Aqueous Asymmetric Supercapacitor. Nano Letters 13:2078-2085.
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