Curved Fragmented Graphenic Hierarchical Architectures for Extraordinary Charging Capacities

Abstract

An approach to assemble hierarchically ordered 3D arrangements of curved graphenic nanofragments for energy storage devices is described. Assembling them into well-defined interconnected macroporous networks, followed by removal of the template, results in spherical macroporous, mesoporous, and microporous carbon microball (3MCM) architectures with controllable features spanning nanometer to micrometer length scales. These structures are ideal porous electrodes and can serve as lithium-ion battery (LIB) anodes as well as capacitive deionization (CDI) devices. The LIBs exhibit high reversible capacity (up to 1335 mAh g ), with great rate capability (248 mAh g at 20 C) and a long cycle life (60 cycles). For CDI, the curved graphenic networks have superior electrosorption capacity (i.e., 5.17 mg g in 0.5 × 10 m NaCl) over conventional carbon materials. The performance of these materials is attributed to the hierarchical structure of the graphenic electrode, which enables faster ion diffusion and low transport resistance.

A Covalently Integrated Reduced Graphene Oxide–Ion‐Exchange Resin Electrode for Efficient Capacitive Deionization

“…1.72 1.96 2015 [67] N-doped electrospun rGO-carbon nanofiber composite (NG-CNF) ≈100 μS cm −1 3.91 2015 [68] SO 3 H-graphene-carbon nanofibers 400 9.54 2015 [69] SO 3 H/NH 2 graphene/activated carbon 500 10.3 2014 [36] Hierarchical hole-enhanced 3D graphene 80 8.0 2018 [70] Spherical macroporous 0.5 × 10 −3 m 5.7 2018 [71] 3D intercalated graphene nanocomposite 500 22.09 2018 [72] MgAl-Ox/G nanohybrids 500 13.6 2018. [37] 3D channel-structured graphene (CSG) 295 9.6 2019 [73] CO 2 activated rGO(AGE) 500 6.26 2019 [39] GO/hierarchical porous carbon 55.72 7.74 2018 [74] SiO 2 activated GO (GR/NMC) 500 18.4 2018 [75] p-phenylenediamine functionalized GO ≈100 μS cm −1 7.88 2018 [76] Mesoporous G@MC heterostructured 500 24.3 J2018 [77] Graphene/Co 3 O 4 composite 250 18.63 2018 [78] N-doped graphitic carbon polyhedrons 500 17.77 2019 [79] EAIERs 802 μS cm Figure 4B,C, and Figures S8, S9, and S11, Supporting Information).…”

Impact of Faradaic Interlayer Confinement and Carbon‐Centered Macrostructure Designs for Ion Capture and the Recovery of Elements

“…[6] as the zero-to three-dimensional architecture of carbon nanomaterials may be controlled on numerous length scales at low cost. [7] By providing a voltage between two electrodes, ions are removed from the salty fluid, and the excess electrode surface charge is balanced through a process called electrosorption, in which dissolved ions are adsorbed into an electric double layer (EDL) within the electrode pore. [8] Because of EDL mechanism, CDI technique has similarity with the ion-adsorption-based energy storage used in supercapacitors.…”

Nitrogen, phosphorus co-doped eave-like hierarchical porous carbon for efficient capacitive deionization

“…9 Although various new concepts of electrochemical desalination have been proposed, the development of highperformance electrode materials is also essential for constructing efficient CDI devices. Various porous carbons, including activated carbon (AC), 10 carbon nanotubes (CNTs), 11,12 graphene, 13 carbon aerogels, 14 and biomass-derived carbon 15 have been widely used as electrode materials for CDI. However, the uncontrolled pore structures, single elemental compositions, and undesirable morphologies reduce the utilization rate of their surface areas and pores, thereby leading to unoptimized or low desalination capacities.…”