Cellulose nanofiber derived carbon aerogel with 3D multiscale pore architecture for high-performance supercapacitors.
TL;DR: In this article, 3D interconnected hierarchical porous carbon aerogels (CNFAs) through engineering the pyrolysis chemistry of CNF are developed to improve the carbon yield and suppress the volume shrinkage, as well as have robust mechanical properties.
Abstract: Carbon materials are highly promising electrode materials for supercapacitors, due to their hierarchical porous structure and large specific surface area. However, the limited specific capacitance and inferior rate capability significantly prevent their practical application. Herein, 3D interconnected hierarchical porous carbon aerogels (CNFAs) through engineering the pyrolysis chemistry of CNF are developed. The obtained CNFAs effectively improve the carbon yield and suppress the volume shrinkage, as well as have robust mechanical properties. As a supercapacitor electrode, the CNFAs-17% electrode exhibits an ultrahigh capacitance of 440.29 F g−1 at 1 A g−1, significantly superior to most reported biomass-based carbon materials. Moreover, the CNFAs-17% assembled symmetric supercapacitor (SSC) achieves an outstanding rate capability (63.29% at 10 mA cm−2), high areal energy density (0.081 mWh cm−2), and remarkable cycling stability (nearly 100% capacitance retention after 7000 cycles). This work offers a simple, effective strategy towards the preparation of promising electrode materials for high-performance energy storage applications.
Citations
More filters
TL;DR: In the face of increasingly severe electromagnetic wave (EMW) pollution, the research of biomass-based carbon materials due to the advantages of being green, renewable, environment-friendly, porous and light has become...
89 citations
TL;DR: In this paper , the authors designed lignin/polypyrrole composite electrode films with microporous and mesoporous structures by electrostatic spinning, carbonization, and in situ polymerization methods.
Abstract: Tailoring the structure and properties of lignin is an important step toward electrochemical applications. In this study, lignin/polypyrrole (PPy) composite electrode films with microporous and mesoporous structures were designed effectively by electrostatic spinning, carbonization, and in situ polymerization methods. The lignin can not only reduce the cost of carbon fiber but also increase the specific surface area of composite films due to the removal of carbonyl and phenolic functional groups of lignin during carbonization. Besides, the compact three-dimensional (3D) conductive network structures were constructed with PPy particles densely coated on the lignin nanofibers, which was helpful to improve the conductivity and fast electron transfer during the charging and discharging processes. The synthesized lignin carbon fibers/PPy anode materials had good electrochemical performance in 1 M H2SO4 electrolyte. The results showed that, at a current density of 1 A g-1, the lignin carbon nanofibers/PPy (LCNFs/PPy) had a larger specific capacitance of 213.7 F g-1 than carbon nanofibers (CNFs), lignin carbon nanofibers (LCNFs), and lignin/PPy fiber (LPAN/PPy). In addition, the specific surface area of LCNFs/PPy reached 872.60 m2 g-1 and the average pore size decreased to 2.50 nm after being coated by PPy. Therefore, the independent non-binder and self-supporting conductive film is expected to be a promising electrode material for supercapacitors with high performance.
15 citations
13 citations
TL;DR: This review discusses the fundamentals and technologies of supercapacitors and utilized materials (including cellulose), and the efficacy of CNS or carbonized-CNS based materials in developing sustainable energy storage devices is highlighted.
Abstract: Sustainable biomass has attracted a great attention in developing green renewable energy storage devices (e.g., supercapacitors) with low-cost, flexible and lightweight characteristics. Therefore, cellulose has been considered as a suitable candidate to meet the requirements of sustainable energy storage devices due to their most abundant nature, renewability, hydrophilicity, and biodegradability. Particularly, cellulose-derived nanostructures (CNS) are more promising due to their low-density, high surface area, high aspect ratio, and excellent mechanical properties. Recently, various research activities based on CNS and/or various conductive materials have been performed for supercapacitors. In addition, CNS-derived carbon nanofibers prepared by carbonization have also drawn considerable scientific interest because of their high conductivity and rational electrochemical properties. Therefore, CNS or carbonized-CNS based functional materials provide ample opportunities in structure and design engineering approaches for sustainable energy storage devices. In this review, we first provide the introduction and then discuss the fundamentals and technologies of supercapacitors and utilized materials (including cellulose). Next, the efficacy of CNS or carbonized-CNS based materials is discussed. Further, various types of CNS are described and compared. Then, the efficacy of these CNS or carbonized-CNS based materials in developing sustainable energy storage devices is highlighted. Finally, the conclusion and future perspectives are briefly conferred.
8 citations
TL;DR: In this article , a hierarchical porous carbon aerogel derived from sodium alginate/melamine composite (SAM) was fabricated by directional freeze-drying combined with simple carbonization and activation process, which achieved a high specific capacitance of 441.80 F/g at a current density of 0.5 A/g.
8 citations
References
More filters
TL;DR: The state-of-the-art progress toward mechanisms, new materials, and novel device designs for supercapacitors is summarized and key technical challenges are highlighted regarding further research in this thriving field.
Abstract: Notably, many significant breakthroughs for a new generation of supercapacitors have been reported in recent years, related to theoretical understanding, material synthesis and device designs. Herein, we summarize the state-of-the-art progress toward mechanisms, new materials, and novel device designs for supercapacitors. Firstly, fundamental understanding of the mechanism is mainly focused on the relationship between the structural properties of electrode materials and their electrochemical performances based on some in situ characterization techniques and simulations. Secondly, some emerging electrode materials are discussed, including metal–organic frameworks (MOFs), covalent organic frameworks (COFs), MXenes, metal nitrides, black phosphorus, LaMnO3, and RbAg4I5/graphite. Thirdly, the device innovations for the next generation of supercapacitors are provided successively, mainly emphasizing flow supercapacitors, alternating current (AC) line-filtering supercapacitors, redox electrolyte enhanced supercapacitors, metal ion hybrid supercapacitors, micro-supercapacitors (fiber, plane and three-dimensional) and multifunctional supercapacitors including electrochromic supercapacitors, self-healing supercapacitors, piezoelectric supercapacitors, shape-memory supercapacitors, thermal self-protective supercapacitors, thermal self-charging supercapacitors, and photo self-charging supercapacitors. Finally, the future developments and key technical challenges are highlighted regarding further research in this thriving field.
1,397 citations
TL;DR: The synthesis of ultra-low-density three-dimensional macroassemblies of graphene sheets that exhibit high electrical conductivities and large internal surface areas are reported, making these materials viable candidates for use in energy storage, catalysis, and sensing applications.
Abstract: We report the synthesis of ultra-low-density three-dimensional macroassemblies of graphene sheets that exhibit high electrical conductivities and large internal surface areas. These materials are prepared as monolithic solids from suspensions of single-layer graphene oxide in which organic sol−gel chemistry is used to cross-link the individual sheets. The resulting gels are supercritically dried and then thermally reduced to yield graphene aerogels with densities approaching 10 mg/cm3. In contrast to methods that utilize physical cross-links between GO, this approach provides covalent carbon bonding between the graphene sheets. These graphene aerogels exhibit an improvement in bulk electrical conductivity of more than 2 orders of magnitude (∼1 × 102 S/m) compared to graphene assemblies with physical cross-links alone (∼5 × 10−1 S/m). The graphene aerogels also possess large surface areas (584 m2/g) and pore volumes (2.96 cm3/g), making these materials viable candidates for use in energy storage, catalysis...
1,089 citations
TL;DR: A hollow graphene/conducting polymer composite fiber is created with high mechanical and electronic properties and used to fabricate novel fiber-shaped supercapacitors that display high energy densities and long life stability.
Abstract: A hollow graphene/conducting polymer composite fiber is created with high mechanical and electronic properties and used to fabricate novel fiber-shaped supercapacitors that display high energy densities and long life stability. The fiber supercapacitors can be woven into flexible powering textiles that are particularly promising for portable and wearable electronic devices.
620 citations
TL;DR: In this article, a series of novel porous carbon materials with different dimensions have been prepared by various methods using biomass as the raw material, which is an important field in the fabrication of supercapacitor electrode materials.
Abstract: The exploration of renewable, cost-effective, and environmentally friendly electrode materials with high adsorption, fast ion/electron transport, and tunable surface chemistry is urgently needed for the development of next-generation biocompatible energy-storage devices. In recent years, biomass-derived carbon electrode materials for energy storage have attracted significant attention because of their widespread availability, renewable nature, and low cost. More importantly, their inherent uniform and precise biological structures can be utilized as templates for fabricating electrode materials with controlled and well-defined geometries. Meanwhile, the basic elements of biomass are carbon, sulfur, nitrogen, and phosphorus. The special naturally ordered hierarchical structures as well as abundant surface properties of biomass-derived carbon materials are compatible with electrochemical reaction processes such as ion transfer and diffusion. To date, a series of novel porous carbon materials with different dimensions have been prepared by various methods using biomass as the raw material, which is an important field in the fabrication of supercapacitor electrode materials. Herein, we summarized recently reported biomass-derived carbon materials with one-dimensional, two-dimensional, and three-dimensional structures and their applications as carbon-based electrode materials for supercapacitors. Finally, the current challenges and future perspectives of the carbon-based electrode materials with respect to the supercapacitor's performance were closely highlighted.
597 citations
TL;DR: In this paper, a series of nanostructured hard carbon materials with controlled architectures is synthesized using a combination of in situ X-ray diffraction mapping, ex situ nuclear magnetic resonance (NMR), electron paramagnetic resonance, electrochemical techniques, and simulations.
Abstract: Hard carbon is one of the most promising anode materials for sodium-ion batteries, but the low Coulombic efficiency is still a key barrier. In this paper, a series of nanostructured hard carbon materials with controlled architectures is synthesized. Using a combination of in situ X-ray diffraction mapping, ex situ nuclear magnetic resonance (NMR), electron paramagnetic resonance, electrochemical techniques, and simulations, an “adsorption–intercalation” mechanism is established for Na ion storage. During the initial stages of Na insertion, Na ions adsorb on the defect sites of hard carbon with a wide adsorption energy distribution, producing a sloping voltage profile. In the second stage, Na ions intercalate into graphitic layers with suitable spacing to form NaC x compounds similar to the Li ion intercalation process in graphite, producing a flat low voltage plateau. The cation intercalation with a flat voltage plateau should be enhanced and the sloping region should be avoided. Guided by this knowledge, nonporous hard carbon material has been developed which has achieved high reversible capacity and Coulombic efficiency to fulfill practical application.
597 citations