Spinous α-Fe₂O₃hierarchical structures anchored on Ni foam for supercapacitor electrodes and visible light driven photocatalysts

Abstract

Spinous α-Fe2O3 hierarchical structures grown on a Ni foam substrate have been successfully obtained by a facile one-step hydrothermal method. The prepared products are functionalized as supercapacitor electrodes without adding any ancillary materials such as carbon black or binders. Their electrochemical properties show a high discharge areal capacitance (681 mF cm(-2) at 1 mA cm(-2)), good rate performance (495 mF cm(-2) at 5 mA cm(-2)) and long-term cycling stability (23.9% loss after 6000 repetitive cycles at 1 mA cm(-2)). Such excellent supercapacitive characteristics could be mainly attributed to their unique spatial structures which provide many active sites and enhance the combination between the electrode and Ni foam to support fast ion and electron transfer. In addition, the prepared α-Fe2O3 product is also used as a photocatalyst for the photocatalytic degradation of several harmful organic dyes under visible light illumination. By comparing the photocatalytic performance towards Congo red dye with other photocatalysts, it was observed that the prepared spinous α-Fe2O3 hierarchical structure exhibited superior photocatalytic performance. Finally, photocatalytic recycle tests showed the superiority of the prepared α-Fe2O3 product. This demonstrates that spinous α-Fe2O3 structures could be promising candidate materials for high-capacity, low-cost supercapacitor electrodes and environmentally friendly photocatalysts.

Flexible Polypyrrole@Fe2O3@Stainless Steel Yarn Composite Electrode for Symmetric Thread‐Like Supercapacitor with Extended Operating Voltage Window in Li2SO4‐Based Aqueous Electrolyte

“…i) Fe 2 O 3 has many merits including high theoretical specific capacitance, inexpensive price and low toxicity, which is a concerned pseudocapacitive material for SCs. [20][21][22] ii) The abundant metal iron source in SSY can be directly used to synthesize Fe 2 O 3 without the use of other ferric/ferrous chemicals, which is in agreement with the concept of resource conservation and low cost. iii) In-situ formation of Fe 2 O 3 on the surface of SSY (Fe 2 O 3 @ SSY) can avoid the introduction of additional current collectors, conducting additives, and polymer binders.…”

Emerging CoMn-LDH@MnO2 electrode materials assembled using nanosheets for flexible and foldable energy storage devices

“…However, single-structured products exhibit low capacitance, which restricts their further application. Therefore, designing CoMn-LDHs-based electrode materials is an efficient strategy to improve their total electrochemical performances through utilizing the synergistic relationships between different electrode materials [28][29][30] . Asymmetric supercapacitors can bridge the advantages of battery-type capacitors and electrochemical double-layer capacitors; they would boost voltage windows as well as capacitance storage ability [31] .…”

Porous α-Fe2O3@C Nanowire Arrays as Flexible Supercapacitors Electrode Materials with Excellent Electrochemical Performances

“…Hematite (α-Fe 2 O 3 ) is an environmentally friendly, low cost, non-toxic and stable electrode material. It possesses a high theoretical capacitance (3265 F g −1 ) and a suitable negative potential working voltage (−1.0 V–0 V) [ 20 , 21 , 22 , 23 , 24 ]. At present, α-Fe 2 O 3 has received extensive attention as high performance anode material for ASCs.…”