Combining Zn_0.76Co_0.24S with S-doped graphene as high-performance anode materials for lithium- and sodium-ion batteries

Abstract

An easy and facile hydrothermal method is presented to synthesize hybrid materials of hollow mesoporous Zn0.76Co0.24S nanospheres anchored on reduced graphene oxide (rGO) sheets (Zn0.76Co0.24S@N/S-rGO), in which the obtained Zn0.76Co0.24S nanospheres are composed of numerous nanoparticles. Being evaluated as anode materials for lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs), the Zn0.76Co0.24S@N/S-rGO composites exhibited a high reversible capacity of 804 and 605 mA h g−1 at the current density of 1 A g−1 after 500 cycles for LIBs and SIBs, respectively. The excellent electrochemical performance of Zn0.76Co0.24S@N/S-rGO composites originates from the synergistic effect between hollow Zn0.76Co0.24S nanospheres and reduction graphene, as well as the void spaces between the neighbouring nanoparticles of Zn0.76Co0.24S providing large contact areas with electrolyte and buffer zone to accommodate the volume variation during the cycling process.

Preparation of Porous Zn0.76Co0.24S Yolk‐Shell Microspheres with Enhanced Electrochemical Performance for Sodium Ion Batteries

“…In Zn 2p spectrum (Figure 3b), two main peaks at 1044.5 eV and 1021.5 eV are indexed to 2p 3/2 and 2p 1/2 of Zn 2+ , respectively, demonstrating the Zn (II) oxidation state of ZCS‐140 sample [37–38] . Similarly, in Co 2p emission spectrum (Figure 3c), two main peaks at 781.5 eV and 797.5 eV are signed to 2p 1/2 and 2p 3/2 of Co 2+ , while other two peaks at 779.0 eV and 793.9 eV are ascribed to 2p 1/2 and 2p 3/2 of Co 3+ , confirming the both existing of Co (III) and Co(II) oxidation state in ZCS‐140 sample [39] . The fitted peaks at 803.0 and 785.5 eV are correspond to the shake‐up satellite peaks of Co.…”

“…[37][38] Similarly, in Co 2p emission spectrum (Figure 3c), two main peaks at 781.5 eV and 797.5 eV are signed to 2p 1/2 and 2p 3/2 of Co 2 + , while other two peaks at 779.0 eV and 793.9 eV are ascribed to 2p 1/2 and 2p 3/2 of Co 3 + , confirming the both existing of Co (III) and Co(II) oxidation state in ZCS-140 sample. [39] The fitted peaks at 803.0 and 785.5 eV are correspond to the shake-up satellite peaks of Co. Besides, the peaks at 163.93 and 162.32 eV are attributed to ZnÀ S bond, and binding energies of 162.86 and 161.83 eV responding to the CoÀ S bond.…”

Graphene triggered catalytic attack on plastic waste produces graphitic shell encapsulation on cobalt nanoparticles for ferromagnetism and stable Li+ ion storage

“…4f) materials were associated with the CoO material reported in the literature, 42,47,[66][67][68][69] though it contained Co nanoparticles and GNPs. Thus, the initial cathodic scan can proceed with the reduction reaction due to the presence of trace impurity functional groups, viz., COOH, CO, O 2− and OH − (located at the surface of GNPs/graphitic carbon), 70 and the formation of nanosized Co-Li-O intermediate cluster 71,72 yields amorphous CoO and Li 2 O products 42,47,[66][67][68][69] with the signature of the rst predominant reduction peak appearing at 0.86 V (Fig. 4d), 0.89 V (Fig.…”

Efficient One-Step Synthesis of a Pt-Free Zn0.76Co0.24S Counter Electrode for Dye-Sensitized Solar Cells and Its Versatile Application in Photoelectrochromic Devices

“…The as-prepared ZCS-CE sample underwent thorough investigation by powder X-ray diffraction analysis to confirm its purity and crystal structure. In Figure 4a, the X-ray diffraction pattern of ZCS-CE shows characteristic peaks at 2θ-diffraction angles of 28.6 • , 47.6 • , and 56.4 • corresponding to the (111)-, (220)-, and (311)-planes of the cubic phase of Zn 0.76 Co 0.24 S (JCPDS #47-1656) [30]. The pronounced sharpness of these peaks and the conspicuous absence of extraneous signals in the diffraction pattern are compelling evidence of the high crystallinity and impeccable purity of the ZCS-CE material.…”