ZnO–Plasma Polymer Fluorocarbon Thin Films for Stable Battery Anodes and High-Output Triboelectric Nanogenerators

Abstract

In this study, ZnO−plasma polymer fluorocarbon (PPFC) nanocomposite thin films were prepared by a mid-range frequency sputtering method using ZnO−polyfluoroethylene−carbon nanotube hybrid targets, and their optical, physical, and surface properties were investigated as functions of the ZnO concentration in the targets. The obtained films exhibited excellent visible light transmittance and hydrophobic characteristics, while their surface roughness and refractive index increased with increasing the ZnO concentration from 6.52 to 15.3 nm and from 1.45 to 1.55, respectively, due to the larger number of ZnO-related absorption states. In addition, the structures and compositions of the films were determined by X-ray diffraction (XRD), grazing incidence small-angle X-ray scattering (GISAXS), and X-ray photoelectron spectroscopy (XPS). It was found that mixed ZnO nanoparticles were well embedded into the PPFC matrix. Finally, we examined the potential applicability of the fabricated ZnO−PPFC nanocomposite thin films in various fields, such as batteries and triboelectric nanogenerators (TENGs). The TENG output voltage increased by approximately 15.8% from 28.05 V for commercial polytetrafluoroethylene (PTFE)-based generators to 32.48 V for the ZnO−PPFC nanocomposite film-based TENG. Furthermore, the ZnO−PPFC nanocomposite thin film demonstrated a stable performance as a battery anode material. While the output of a ZnO reference electrode decreased by approximately 74.5% after 100 cycles, the output of a ZnO−PPFC anode decreased by only 12.4% and remained stable afterward.

Analogous Design of a Microlayered Silicon Oxide‐Based Electrode to the General Electrode Structure for Thin‐Film Lithium‐Ion Batteries

“…Ring-shaped light scattering patterns were observed depending on the orientation of the scatterers, suggesting that individual SiO x species are well scattered at regular spacing without formation of agglomerates in the thin-film. [33][34][35] In-plane scattering profiles were also observed from the inset image at the Yoneda wing position. The scattering angles are reported as the scattering vector q, which incorporates the wavelength of the Xray source 𝜆.…”

“…The TF-SiO x 60/PPFC developed in this study is one of the best of all papers reported for using Si-based anodes in terms of cycle life and capacity retention. The fabrication method using these mixed targets had the advantage of depositing various materials (Cu, [33] Ag, [34] and ZnO [35] ), suggesting that high-quality thinfilms for TF-LIBs can be deposited using materials other than SiO x . Figure 5d schematically shows the operating mechanism for the proposed TF-SiO x 60/PPFC TF-SiO x 100 thin-films based on the above results and discussions.…”

Confluence of ZnO and PTFE Binder for Enhancing Performance of Thin‐Film Lithium‐Ion Batteries

“…The lithium storage capacity of all thin films was assessed using galvanostatic charge-discharge profiles within a voltage range of 0-2 V Li versus Li/Li + at a current rate of 0.05C (the theoretical capacity at 1C is 987 mAh g À1 , and the theoretical mass density is 5.61 g cm À3 ). [35] Figure 4a-d presents the initial five charge-discharge curves for both the ZnO and ZnO/PTFE thin films. Notably, at the slow current rate of 0.05C, the ZnO and ZnO/PTFE (5,10,15) thin films demonstrated high initial discharge capacities of 2741, 2654, 2577, and 1946 mAh g À1 , corresponding to volumetric capacities of 15 079, 14 867, 14 434, and 10 786 mAh cm À3 and areal capacities of 0.18, 0.178, 0.173, and 0.129 mAh cm À2 , respectively.…”

Synthesis of Zinc Oxide Nanorods from Zinc Borate Precursor and Characterization of Supercapacitor Properties

“…This aspect is diversified to further enhance performance. Consequently, ZnO metal oxide performs with a high specific capacity of approximately 978 mAh•g −1 , exceptionally well as a supercapacitor electrode material [17][18][19]. In this context, Zhang et al conducted the synthesis of ZnO with nano-rod geometry on a silicon wafer and found a specific capacitance (Cs) of 43 mF•cm −2 at a current density of 1 mA•cm −2 [20].…”