Three-Dimensional Core-Branch α-Fe2O3@NiO/Carbon Cloth Heterostructured Electrodes for Flexible Supercapacitors

Abstract

A convenient and scalable hydrothermal method was developed for the fabrication of the core-branch Fe 2 O 3 @NiO nanorods arrays directly grown on flexible carbon cloth (denoted as Fe 2 O 3 @NiO/CC). Such a unique architecture was applied as an electrode of the supercapacitors. As a result, the Fe 2 O 3 @NiO/CC exhibited a high areal capacitance ∼800 mF cm −2 at 10 mA cm −2 , which was about 10 times increase with respect to Fe 2 O 3 nanorods array grown on carbon cloth (Fe 2 O 3 /CC). The Fe 2 O 3 @NiO/CC also had the long life cycle (96.8 % capacitance retention after 16,000 cycles) and remarkable rate capability (44.0 % capacitance loss at a very large current density of 100 mA cm −2). The superior performance of the Fe 2 O 3 @NiO/CC should be ascribed to the reduction of the contact resistance and the free-standing structure of the flexible electrode. This study provides a novel strategy to construct high-performance flexible electrode materials with unique core-branch structure by incorporating two different pseudocapacitive materials.

Metal‐oxide nanomaterials recycled from E‐waste and metal industries: A concise review of applications in energy storage, catalysis, and sensing

“…26, Copyright 2018 Wiley, C, TEM images showing the comparison of raw red mud in the raw, unprocessed state (a‐b) and (c‐d) after 10‐hour ball milling, spherical NPs have been obtained, image adapted with permission from Ref. 29, Copyright 2019 Wiley [Colour figure can be viewed at wileyonlinelibrary.com]…”

“…The waste‐derived porous activated material, therefore, can be used as an effective negative electrode for flexible energy storage applications. But, it is to be noted that a similar material (the core‐branch Fe 2 O 3 @NiO nanorods arrays directly grown on flexible carbon cloth) synthesized using hydrothermal route exhibited better performance with an exceptional cycling performance of 96.8% initial capacitance retention at a current density of 20 mA cm −2 even after 16 000 cycles 29 …”

“…B, Ragone plot demonstrating that waste‐based red mud and waste FeO x show superior behavior as supercapacitors to non‐waste based AC/FCO (mixed metal)‐based and RuO 2 supercapacitors (adapted with permission from Ref. 29, Copyright 2019 Wiley) [Colour figure can be viewed at wileyonlinelibrary.com]…”

Porous Fe2O3 Nanorods on Hierarchical Porous Biomass Carbon as Advanced Anode for High-Energy-Density Asymmetric Supercapacitors

“…Carbon materials play a role as negative electrodes, using the electrical double layer to accumulate energy, while the specific capacitance is trapped at an intermediate level of 100-200 F g −1 (Zhu et al, 2011;Sahu et al, 2017;Wang et al, 2019). Recent studies have reported that pseudocapacitive anodes can deliver higher charge storage capacities than carbon materials, such as MoO 3 (Zhang et al, 2019), V 2 O 5 (Guo et al, 2015), WO 3 (Yun T. G. et al, 2019), TiN Sun et al, 2020, Fe 3 (Arun et al, 2019), FeOOH (Chen et al, 2016), and Fe 2 O 3 (Yun X. et al, 2019;Le et al, 2020;Zhang et al, 2020). Among them, α-Fe 2 O 3 is chosen as a potential candidate for ASCs because of its natural abundance, eco-friendly nature, excellent physicochemical stability, large theoretical capacitance (∼3,625 F g −1 ), and high hydrogen evolution potential in aqueous solution (Han et al, 2014;Nithya and Arul, 2016;.…”

Flexible FeVOx porous nanorods on carbon cloth for long-life aqueous energy storage

“…3c, we have observed that CFV x displays improved area specific capacitance and rate property compared to previously estimated vanadium-based, iron-based electrode materials. 20–24 The CFV x electrode also displays an outstanding cycling property with a capacitance retention of 97.14% over 12 000 cycles (Fig. 3e).…”