Flexible CuO Nanosheets/Reduced-Graphene Oxide Composite Paper: Binder-Free Anode for High-Performance Lithium-Ion Batteries

Abstract

Flexible free-standing CuO nanosheets (NSs)/reduced graphene oxide (r-GO) hybrid lamellar paper was fabricated through vacuum filtration and hydrothermal reduction processes. A unique three-dimensional nanoporous network was achieved with CuO NSs homogeneously embedded within the r-GO layers. This hybrid lamellar composite paper was examined as a binder-free anode for lithium ion batteries, and demonstrated excellent cyclic retention with the specific capacity of 736.8 mA h g(-1) after 50 cycles. This is much higher than 219.1 mA h g(-1) of the pristine CuO NSs and 60.2 mA h g(-1) of r-GO film at the same current density of 67 mA g(-1). The high capacitance and excellent cycling performance were generated from the integrated nanoporous structure compose of CuO NSs spaced r-GO layers, which offered an efficient electrically conducting channels, favored electrolyte penetration, and buffered to the volume variations during the lithiation and delithiation process. These outstanding electrochemical capabilities of CuO NSs/r-GO paper holds great promise for flexible binder-free anode for lithium ion batteries.

Graphene oxide: A promising nanomaterial for energy and environmental applications

“…The pulverization process of transition metal oxide (TMO) induced rapid capacity degradation can be effectively suppressed in the RGO/TMO hybrids [64][65][66][67][68][69][87][88][89][90][91][92][93][94]. For instance, two-step synthesized Mn 3 O 4 /RGO hybrid renders a high specific capacity up to $900 mA h g À 1 (near the theoretical capacity) as well as good rate capability and cycling stability [87].…”

MnO2 decorated on carbon sphere intercalated graphene film for high-performance supercapacitor electrodes

“…In order to further confirm the distribution and uniformity of CG and MnO 2 , the EDX elemental mapping images (Fig. 3g- respectively [16,19]. It is obviously seen that the peak intensity of C-O and C=O is much weaker than that of C−C, which indicates that most of the oxygen-containing groups are removed after annealed treatment.…”

“…But most of the MnO 2 /graphene composites are powders, when used as electrodes, current collector, binder and conductive additives were needed. Graphene film is an ideal substrate for fabricating binder-free MnO 2 based electrodes, but the strong aggregation tendency of graphene sheets leads to severe decrease of active surface area and the ion diffusion rate, resulting in lower capacity and charge-discharge rates [19,20].…”

A novel porous CuO nanorod/rGO composite as a high stability anode material for lithium-ion batteries

“…8, the Nyquist plots of both electrodes were carried out in a frequency range from 0.01 to 100 kHz. Generally, the high frequency semicircle corresponds to the charge transfer resistance on electrode/electrolyte interface and the slope of the straight line at low frequency corresponds to the lithium-diffusion process within electrodes [37] . In our case, the transfer resistance for CuO/rGO electrode is smaller than pure CuO electrode, because the synergetic effect of the CuO nanorods, in combination with the high electronic conductivity of the rGO sheets and the unique structures of porous CuO nanorods with vermicular pore channel, dominated the excellent electrochemical performance of CuO/rGO nanocomposite.…”