3D porous framework of ZnO nanoparticles assembled from double carbon shells consisting of hard and soft carbon networks for high performance lithium ion batteries

Abstract

Low electronic conductivity and large volume variation result in inferior lithium storage performance of ZnO. To overcome these shortcomings of ZnO, herein ZnO nanoparticles are encapsulated in resorcinol–formaldehyde resin-derived hard carbon and then further assembled into a 3-dimensional mesoporous framework structure using a polyvinyl pyrrolidone-derived soft carbon network. The synthesis methods include the polymerization of resorcinol–formaldehyde resin and a polyvinyl pyrrolidone-boiling method. ZnO@dual carbon has af large specific surface area (153.7 m2 g−1) and high porosity. It exhibits excellent cycling performance and high rate capability. After 350 cycles at 500 mA g−1, the ZnO@dual carbon still delivers a discharge capacity of 701 mAh g−1 while the actual discharge capacity of ZnO reaches 950.9 mAh g−1. At 2 A g−1, ZnO@dual carbon delivers the average discharge capacity of 469.6 mAh g−1. The electrochemical performance of ZnO@dual carbon is remarkably superior to those of ZnO@single carbon, pure carbon and pure ZnO nanoparticles, demonstrating the superiority of the dual carbon-assembly structure. This composite structure greatly improves the structural stability of ZnO, enhances its electron conductivity and overall electron transport capacity; which facilitates electrolyte penetration and Li ion diffusion, leading to improved cycling stability and good rate capability.

ZnO‐Embedded Expanded Graphite Composite Anodes with Controlled Charge Storage Mechanism Enabling Operation of Lithium‐Ion Batteries at Ultra‐Low Temperatures

“…Notably, these values are significantly lower than those reported in previous studies that focused on using carbon supports to enhance ZnO performance (Table S1, Supporting Information). [ 24,31–38 ]…”

“…Notably, these values are significantly lower than those reported in previous studies that focused on using carbon supports to enhance ZnO performance (Table S1, Supporting Information). [24,[31][32][33][34][35][36][37][38] The surface chemistry of the EG and ZnO-EG composites was studied using X-ray photoelectron spectroscopy (XPS). The XPS survey scans showed a gradual increase in the atomic oxygen to carbon (O/C) ratio with increasing amounts of ZnO nanoparticles, from 0.05 for EG to 0.07 for ZnO-EG-1 to 0.1 for ZnO-EG-2 (Figure 2c).…”

MOF-Derived Long Spindle-like Carbon-Coated Ternary Transition-Metal-Oxide Composite for Lithium Storage

“…The peak near 0.01 V relates to Li + intercalation into the amorphous porous carbon, causing the carbon matrix lithiation. 17 , 27 During the first anode cycle, two oxidation peaks were detected at 1.6 and 1.8 V, corresponding to the reversible oxidation of (FeCoNi) 0 to (FeCoNi) 3 O 4 . Subsequently, the CV cycle curves and peak locations of the sample almost overlap, indicating good cycle stability and reversibility.…”

“…Owing to the conversion reaction, the (FeCoNi) 3 O 4 phase transforms into the (FeCoNi) 0 phase; however, the peak is related to the electrolyte decomposition, which forms the solid electrolyte interface (SEI) layer. The peak near 0.01 V relates to Li + intercalation into the amorphous porous carbon, causing the carbon matrix lithiation. , During the first anode cycle, two oxidation peaks were detected at 1.6 and 1.8 V, corresponding to the reversible oxidation of (FeCoNi) 0 to (FeCoNi) 3 O 4 . Subsequently, the CV cycle curves and peak locations of the sample almost overlap, indicating good cycle stability and reversibility.…”

Ultrasmall ZnO Nanocrystals Confined in Honeycombed N‐Doped Carbon for High‐Performance and Stable Lithium/Sodium Ion Batteries

“…Via the in situ transmission electron microscope (TEM) technique, the improved performance was confirmed to be originated from the mesoporous amorphous carbon layers, which effectively relieved the volume expansion and maintained the structural integrity of the material as well as suppressed the growth of adversely large, stable Zn grains and eased the formation of a LiZn alloy. Zhang et al [ 19 ] synthesized the composite of ZnO nanoparticles confined in double carbon shells consisting of hard carbon and soft carbon network (ZnO@dual carbon). The ZnO@dual carbon delivered excellent cycling performance (701 mAh g −1 after 350 cycles at 0.5 A g −1 ) and high rate capability (469 mAh g −1 at 2 A g −1 ), which might be attributed to the unique dual carbon‐assembling structure.…”