3D Exfoliated Carbon Paper toward Highly Loaded Aqueous Energy Storage Applications

Abstract

Commercial electrodes need high mass loadings to realize superior energy and power densities. However, good electrochemical properties are usually achieved in the electrodes with ultrathin active materials (e.g., <1 mg cm−2). Good performance and high mass loading are often mutually exclusive characteristics. Herein, a unique 3D exfoliated carbon paper (EC) is demonstrated using a facile electrochemical method to support high mass loading MnO2 materials. The 3D‐interconnected graphene/graphite network, highly porous structure, as well as the strong interaction between the active materials and the substrate, allow efficient charge transport in the composite electrode, addressing the traditional limitations in high mass loading electrodes. The deposited MnO2 (mass loading: 9.5–10 mg cm−2) achieves a remarkable capacitive performance with high areal and gravimetric capacitances of 5.1 F cm−2 and 537 F g−1, respectively. A Zn–MnO2 battery is also assembled using MnO2/EC as the cathode. An excellent specific capacity of 368 mAh g−1 is also delivered. This MnO2/EC outperforms most of the reported MnO2‐based electrodes with similar loadings for capacitive and Zn‐ion battery applications, highlighting the great application potential of the 3D carbon paper support in electrochemical energy storage.

Constructing Advanced Aqueous Zinc‐Ion Batteries with 2D Carbon‐Rich Materials

“…h) SEM image of Na:MnO 2 /GCF cathode. Reproduced with permission [77b] . Copyright 2020, John Wiley and Sons.…”

In situ generation of exfoliated graphene layers on recycled graphite rods for enhanced capacitive performance of Ni–Co binary hydroxide

“…Also, the deconvolution of O 1s of FEGR indicates the formation of surface functional groups which is consistent with the deconvolution of its C 1s. [48][49][50] Further investigation was done to conrm the presence of the functional groups and defects that are introduced to the surface of the FEGR during the electrochemical partial exfoliation using the FT-IR spectra, Raman spectroscopy, and contact angle measurements. Fig.…”

“…It is clearly obvious from these results that there is an increase in the degree of disorder (roughness) of FEGR electrode due to the inserted functional groups and defects that are generated during the production of graphene on the surface of bulk graphite by electrochemical exfoliation. 41,44,46,49,[53][54][55] Also, the more broadening and increase in the wavenumber of G band in FEGR electrode compared to the RGR electrode conrms the more defects formed at the surface of FEGR electrode. 52 The decrease of full width at half a maximum of the 2D band of FEGR electrode compared to RGR is a good indication of the successful exfoliation of graphite into graphene layers as obtained from the SEM analysis, see Fig.…”

A Review on Nano-/Microstructured Materials Constructed by Electrochemical Technologies for Supercapacitors

“…It is the most used electrochemical approach for graphene production due to its high exfoliation efficiency. With inorganic acids (e.g., H 2 SO 4 [ 78 , 84 ], HNO 3 [ 85 , 86 ], and H 3 PO 4 [ 87 ]) or salts (e.g., KNO 3 [ 88 ] and (NH 4 ) 2 SO 4 [ 89 ]) as supporting electrolytes, a high exfoliation potential (e.g., 3–10 V) can generate single-layer or multilayer graphene sheets from graphite. For example, Parvez et al exfoliated graphite foils in sulfuric acid aqueous solutions with concentrations of 0.1, 1, and 5 M [ 84 ].…”

“…The seamless integration between the top layer and the graphite bottom ensured fast electron conduction pathways. Besides improving electrolyte wettability, the oxygen moieties served as anchoring sites for depositing guest materials for polyaniline [ 27 ], polypyrrole [ 105 ], manganese oxides [ 86 ], vanadium oxides [ 37 ], iron oxides [ 35 , 106 ], nickel–cobalt double hydroxides [ 106 ], and molybdenum-based materials [ 28 ].

Fig.

…”