Alkyldimethylbetaine-Assisted Development of Hollow Urchinlike CuO Microspheres and Application for High-Performance Battery Anodes

Abstract

A new approach to develop novel hollow urchinlike copper oxide (CuO) microspheres by the hydrothermal method was reported, and zwitterionic alkyldimethylbetaine (BS) surfactants were employed as templates in the classic copper–ammonia complex systems. Effects of numerous environmental factors on the morphology of CuO particles were studied systematically, in which the concentration and structure of BS predominantly affected the developed CuO materials. It was noticed that hollow urchinlike CuO microspheres were generally formed in the presence of BS regardless of the reaction temperature and time and the source of copper ions. Generally speaking, high concentrations of BS and BS with longer chain length strongly favored the formation of hollow urchinlike CuO microspheres. The microstructures of synthesized CuO particles were studied in detail, and the corresponding formation mechanism of hollow urchinlike CuO microspheres was also proposed based on the selective adsorption of BS on the particular crystal facets of CuO crystals. Moreover, hollow urchinlike CuO microspheres showed excellent performance in the lithium-ion batteries as anode materials with a reversible capability of 511 mA h·g –1 at 0.1 C after 40 charge–discharge cycles, which was one of the best values of CuO materials reported in this field.

Three-dimensional clusters of peony-shaped CuO nanosheets as a high-rate anode for Li-ion batteries

“…For the anodic scan, two signals peaked at 2.51 and 2.74 V indicate the oxidization of Cu to Cu 2 O and the formation of CuO phase, respectively. [21][22][23] The corresponding reactions could be described by eqn (4)-( 8): [21][22][23] The discharge reactions:…”

“…4e). 18,[21][22][23][28][29][30][31][32][33] This is attributed to: (i) the distinctive structure of this three-dimensional peony-shape nanosheets facilitates the inltration of liquid electrolyte and provide more available interfaces for electrochemical reactions, thus accelerating electron/ion transfer; and (ii) the unique peony-like structure can also alleviate the severe volume expansion during charge/discharge process. The cycling durability of the TCP-CuO electrode was tested by rst discharging/charging at 0.1 A g À1 for 7 cycles and then 1 A g À1 for 100 cycles.…”

“…(d) Rate performance of the TCP-CuO electrode at various discharge rates. (e) Comparison of high rate property of the TCP-CuO electrode with other CuO-based electrodes, such as hollow CuO@C microsphere, 21 CuO leaf-like nanostructure, 25 Cu 2 O/CuO/rGO nanosheets, 26 CuO/Cu 2 O/C composites,27 CuO nanofibers,28 CuO nanowire arrays,18 CuO porous nanosheets,29 CuO nanochains, 22 yucca fern shaped CuO nanowires,30 and hollow urchinlike CuO microspheres 23. (f) Cycling performance of the TCP-CuO electrode as well as coulombic efficiency at 1 A g À1 .…”

“…CuO leaf-like nanostructure,25 Cu 2 O/CuO/rGO nanosheets,26 CuO/Cu 2 O/C composites,27 CuO nanofibers,28 CuO nanowire arrays,18 CuO porous nanosheets,29 CuO nanochains,22 yucca fern shaped CuO nanowires,30 and hollow urchinlike CuO microspheres 23. (f) Cycling performance of the TCP-CuO electrode as well as coulombic efficiency at 1 A g À1 .…”