Utilizing Cyclic Voltammetry to Understand the Energy Storage Mechanisms for Copper Oxide and its Graphene Oxide Hybrids as Lithium-Ion Battery Anodes.

Invited for this month's cover is the group of Robert A. W. Dryfe at the University of Manchester in collaboration with William Blythe Ltd.

Utilizing Cyclic Voltammetry to Understand the Energy Storage Mechanisms for Copper Oxide and its Graphene Oxide Hybrids as Lithium-Ion Battery Anodes.

Graphene-based materials have been extensively researched as a means improve the electrochemical performance of transition metal oxides in Li-ion battery applications, however an understanding of the effect of the different synthesis routes, and the factors underlying the oft-stated better performance of the hybrid materials (compared to the pure metal oxides) is not always demonstrated. For the first time, we report a range of synthetic routes to produce graphene oxide (GO)-coated CuO, micro-particle/GO "bundles" as well as nano-particulates decorated on GO sheets to enable a comparison with CuO and its carbon-coated analogue, as confirmed using scanning electron microscopy (SEM) imaging and Raman spectroscopy. Cyclic voltammetry was utilized to probe the lithiation/delithiation mechanism of CuO by scanning at successively decreasing vertex potentials, uncovering the importance of a full reduction to Cu metal on the reduction step.