Designing of Carbon Nitride Supported ZnCo2O4 Hybrid Electrode for High-Performance Energy Storage Applications

Abstract

this study reports a unique graphitic-c 3 n 4 supported Znco 2 o 4 composite, synthesized through a facile hydrothermal method to enhance the electrochemical performance of the electrode. the g-c 3 n 4 @ Znco 2 o 4 hybrid composite based electrode exhibits a significant increase in specific surface area and maximum specific capacity of 157 mAhg −1 at 4 Ag −1. Moreover, g-c 3 n 4 @Znco 2 o 4 electrode maintained significant capacity retention of 90% up to 2500 cycles. Utilizing this composite in the development of the symmetric device, g-c 3 n 4 @Znco 2 o 4 //g-c 3 n 4 @Znco 2 o 4 displays a specific capacity of 121 mAhg −1. The device exhibits an energy density of 39 Whkg −1 with an equivalent power density of 1478 Wkg −1. A good cycling stability performance with an energy efficiency of 75% and capacity retention of 71% was observed up to 10,000 cycles. The superior performance of g-C 3 n 4 @Znco 2 o 4 is attributed to the support of the g-c 3 n 4 which increases the surface area, electroactive sites and provides chemical stability for electrochemical performance. the outstanding performance of this exclusive device symbolizes remarkable progress in the direction of high-performance energy storage applications.

Effect of reaction time and PVP contents on morphologies of hierarchical 3D flower‐like ZnCo 2 O 4 microstructures for energy storage devices

“…Corresponding peaks around 1021.0/1020.8/1021.0/1020.9 eV (Z1) and 1044.1/1043.9/1044.1/1044 eV (Z2) for PVP‐L@6, PVP‐H@6, PVP‐L@12, and PVP‐H@12, respectively, were observed, indicating Zn 2+ in the normal state in ZCO samples. For all the samples, the difference in binding energies between the spin‐orbit interactions of the two transitions (Zn 2 p 3/2 and 2 p 1/2 ) was estimated to be ~23 eV, which is consistent with the results of a previous report 25,34‐36 . Similarly, a comparison of the Co 2 p core‐level spectra for all the samples is shown in Figure 6C.…”

“…X‐ray diffraction (XRD) patterns of all samples are shown in Figure 1. For all samples, the diffraction peaks are located at 2 θ values around 18.70°, 31.29°, 36.68°, 38.70°, 44.68°, 55.68°, 59.47°, 65.09°, and 77.30°, which correspond to the (111), (220), (311), (222), (400), (422), (511), (440), and (533) planes of standard ZnCo 2 O 4 (Joint Committee on Powder Diffraction Standards Card No: 23‐1390), 9,25 respectively. The average crystallite sizes of PVP‐L@6 (PVP lower concentration [10 mg] at lower reaction time [180°C/6 h]), PVP‐H@6 (PVP higher concentration [50 mg] at lower reaction time [180°C/6 h]), PVP‐L@12 (PVP lower concentration [10 mg] at higher reaction time [180°C/12 h]), and PVP‐H@12 (PVP higher concentration [50 mg] at higher reaction time [180°C/12 h]) were approximately 17.1, 16.5, 16.1, and 16.2 nm, respectively, determined from the (311) diffraction peak using Scherer's formula 26,27 …”

“…For all the samples, the difference in binding energies between the spin-orbit interactions of the two transitions (Zn 2p 3/2 and 2p 1/2 ) was estimated to be $23 eV, which is consistent with the results of a previous report. 25,[34][35][36] Similarly, a comparison of the Co 2p core-level spectra for all the samples is shown in Figure 6C. The asymmetric spectra exhibited three different regions of peaks, which were related to the Co in the +2 and +3 states, along with a satellite peak.…”

“….70 ,44.68 , 55.68 , 59.47 , 65.09 , and 77.30 , which correspond to the (111), (220), (311), (222), (400), (422), (511), (440), and (533) planes of standard ZnCo 2 O 4 (Joint Committee on Powder Diffraction Standards Card No: 23-1390),9,25 respectively. The average crystallite sizes of PVP-L@6 (PVP lower concentration [10 mg] at lower…”

In situ microwave-assisted solvothermal synthesis via morphological transformation of ZnCo2O4 3D nanoflowers and nanopetals to 1D nanowires for hybrid supercapacitors

“…Cobalt-based oxides, with their advantages of great theoretical specific capacity and significant redox response, are an excellent battery-type cathode material for hybrid supercapacitor applications. 16,17 Also, spinel metal cobaltites such as NiCo 2 O 4 , 18 MnCo 2 O 4 , 19 CuCo 2 O 4 , 20 MgCo 2 O 4 , 21 and ZnCo 2 O 4 22 are favorable electrode materials for hybrid supercapacitors because of their low electrical resistivity and excellent redox performance than the pristine metal oxides. The zinc cobaltite (ZnCo 2 O 4 ; ZCO) has been viewed as a capable electrode material for supercapacitors, 23 Li-ion batteries, 24 and electrocatalysts 25 because of cost-benefit and scalable alternative; moreover, it has several benefits such as low price, abundant resources and environmental friendliness.…”