Interacted Ternary Component Ensuring High-Security Eutectic Electrolyte for High Performance Sodium-Metal Batteries.

Due to the intrinsic flame-retardant, eutectic electrolytes are considered a promising candidate for sodium-metal batteries (SMBs). However, the high viscosity and ruinous side reaction with Na metal anode greatly hinder their further development. Herein, based on the Lewis acid-base theory, a new eutectic electrolyte (EE) composed of sodium bis(trifluoromethanesulfonyl)imide (NaTFSI), succinonitrile (SN), and fluoroethylene carbonate (FEC) is reported. As a strong Lewis base, the ─C≡N group of SN can effectively weaken the interaction between Na+ and TFSI-, achieving the dynamic equilibrium and reducing the viscosity of EE. Moreover, the FEC additive shows a low energy level to construct thicker and denser solid electrolyte interphase (SEI) on the Na metal surface, which can effectively eliminate the side reaction between EE and Na metal anode. Therefore, EE-1:6 + 5% FEC shows high ionic conductivity (2.62 mS cm-1) and ultra-high transference number of Na+ (0.96). The Na||Na symmetric cell achieves stable Na plating/stripping for 1100 h and Na||Na3V2(PO4)3/C cell shows superior long-term cycling stability over 2000 cycles (99.1% retention) at 5 C. More importantly, the Na||NVP/C pouch cell demonstrates good cycling performance of 102.1 mAh g-1 after 135 cycles at 0.5 C with an average coulombic efficiency of 99.63%.

Coordination Engineering of Defective Cobalt-Nitrogen-Carbon Electrocatalysts with Graphene Quantum Dots for Boosting Oxygen Reduction Reaction.

Developing efficient and robust metal-nitrogen-carbon electrocatalysts for oxygen reduction reaction (ORR) is of great significance for the application of hydrogen-oxygen fuel cells and metal-air batteries. Herein, a coordination engineering strategy is developed to improve the ORR kinetics and stability of cobalt-nitrogen-carbon (Co-N-C) electrocatalysts by grafting the oxygen-rich graphene quantum dots (GQDs) onto the zeolite imidazole frameworks (ZIFs) precursors. The optimized oxygen-rich GQDs-functionalized Co-N-C (G-CoNOC) electrocatalyst demonstrates an increased mass activity, nearly two times higher than that of pristine defective Co-N-C electrocatalyst, and retains a stability of 90.0% after 200 h, even superior to the commercial Pt/C. Comprehensive investigations demonstrate that the GQDs coordination can not only decrease carbon defects of Co-N-C electrocatalysts, improving the electron transfer efficiency and resistance to the destructive free radicals from H2 O2 , but also optimize the electronic structure of atomic Co active site to achieve a desired adsorption energy of OOH- , leading to enhanced ORR kinetics and stability by promoting further H2 O2 reduction, as confirmed by theoretical calculations and experimental results. Such a coordination engineering strategy provides a new perspective for the development of highly active noble-metal-free electrocatalysts for ORR.

Dual Molecules Cooperatively Confined In-Between Edge-oxygen-rich Graphene Sheets as Ultrahigh Rate and Stable Electrodes for Supercapacitors.

Noncovalent modification of carbon materials with redox-active organic molecules has been considered as an effective strategy to improve the electrochemical performance of supercapacitors. However, their low loading mass, slow electron transfer rate, and easy dissolution into the electrolyte greatly limit further practical applications. Herein, this work reports dual molecules (1,5-dihydroxyanthraquinone (DHAQ) and 2,6-diamino anthraquinone (DAQ)) cooperatively confined in-between edge-oxygen-rich graphene sheets as high-performance electrodes for supercapacitors. Cooperative electrostatic-interaction on the edge-oxygen sites and π-π interaction in-between graphene sheets lead to the increased loading mass and structural stability of dual molecules. Moreover, the electron tunneling paths constructed between edge-oxygen groups and dual molecules can effectively boost the electron transfer rate and redox reaction kinetics, especially at ultrahigh current densities. As a result, the as-obtained electrode exhibits a high capacitance of 507 F g-1 at 0.5 A g-1 , and an unprecedented rate capability (203 F g-1 at 200 A g-1 ). Moreover, the assembled symmetrical supercapacitor achieves a high energy density of 17.1 Wh kg-1 and an ultrahigh power density of 140 kW kg-1 , as well as remarkable stability with a retention of 86% after 50 000 cycles. This work may open a new avenue for the efficient utilization of organic materials in energy storage and conversion.

Tin Nanodots Derived From Sn2+ /Graphene Quantum Dot Complex as Pillars into Graphene Blocks for Ultrafast and Ultrastable Sodium-Ion Storage.

Tin (Sn) is considered to be an ideal candidate for the anode of sodium ion batteries. However, the design of Sn-based electrodes with maintained long-term stability still remains challenging due to their huge volume expansion (≈420%) and easy pulverization during cycling. Herein, a facile and versatile strategy for the synthesis of nitrogen-doped graphene quantum dot (GQD) edge-anchored Sn nanodots as the pillars into reduced graphene oxide blocks (NGQD/Sn-NG) for ultrafast and ultrastable sodium-ion storage is reported. Sn nanodots (2-5 nm) anchored at the edges of "octopus-like" GQDs via covalent SnOC/SnNC bonds function as the pillars that ensure fast Na-ion/electron transport across the graphene blocks. Moreover, the chemical and spatial (layered structure) confinements not only suppress Sn aggregation, but also function as physical barriers for buffering volume change upon sodiation/desodiation. Consequently, the NGQD/Sn-NG with high structural stability exhibits excellent rate performance (555 mAh g-1 at 0.1 A g-1 and 198 mAh g-1 at 10 A g-1 ) and ultra-long cycling stability (184 mAh g-1 remaining even after 2000 cycles at 5 A g-1 ). The confinement-induced synthesis together with remarkable electrochemical performances should shed light on the practical application of highly attractive tin-based anodes for next generation rechargeable sodium batteries.

Advanced Li-Ion Batteries with High Rate, Stability, and Mass Loading Based on Graphene Ribbon Hybrid Networks.

To optimize the cycle life and rate performance of lithium-ion batteries (LIBs), ultra-fine Fe2 O3 nanowires with a diameter of approximately 2 nm uniformly anchored on a cross-linked graphene ribbon network are fabricated. The unique three-dimensional structure can effectively improve the electrical conductivity and facilitate ion diffusion, especially cross-plane diffusion. Moreover, Fe2 O3 nanowires on graphene ribbons (Fe2 O3 /GR) are easily accessible for lithium ions compared with the traditional graphene sheets (Fe2 O3 /GS). In addition, the well-developed elastic network can not only undergo the drastic volume expansion during repetitive cycling, but also protect the bulk electrode from further pulverization. As a result, the Fe2 O3 /GR hybrid exhibits high rate and long cycle life Li storage performance (632 mAh g-1 at 5 A g-1 , and 471 mAh g-1 capacity maintained even after 3000 cycles). Especially at high mass loading (≈4 mg cm-2 ), the Fe2 O3 /GR can still deliver higher reversible capacity (223 mAh g-1 even at 2 A g-1 ) compared with the Fe2 O3 /GS (37 mAh g-1 ) for LIBs.

Nanocellulose: a promising nanomaterial for advanced electrochemical energy storage.

Nanocellulose has emerged as a sustainable and promising nanomaterial owing to its unique structures, superb properties, and natural abundance. Here, we present a comprehensive review of the current research activities that center on the development of nanocellulose for advanced electrochemical energy storage. We begin with a brief introduction of the structural features of cellulose nanofibers within the cell walls of cellulose resources. We then focus on a variety of processes that have been explored to fabricate nanocellulose with various structures and surface chemical properties. Next, we highlight a number of energy storage systems that utilize nanocellulose-derived materials, including supercapacitors, lithium-ion batteries, lithium-sulfur batteries, and sodium-ion batteries. In this section, the main focus is on the integration of nanocellulose with other active materials, developing films/aerogel as flexible substrates, and the pyrolyzation of nanocellulose to carbon materials and their functionalization by activation, heteroatom-doping, and hybridization with other active materials. Finally, we present our perspectives on several issues that need further exploration in this active research field in the future.

Amorphous Red Phosphorus Embedded in Sandwiched Porous Carbon Enabling Superior Sodium Storage Performances.

The red P anode for sodium ion batteries has attracted great attention recently due to the high theoretical capacity, but the poor intrinsic electronic conductivity and large volume expansion restrain its widespread applications. Herein, the red P is successfully encapsulated into the cube shaped sandwich-like interconnected porous carbon building (denoted as P@C-GO/MOF-5) via the vaporization-condensation method. Superior cycling stability (high capacity retention of about 93% at 2 A g-1 after 100 cycles) and excellent rate performance (502 mAh g-1 at 10 A g-1 ) can be obtained for the P@C-GO/MOF-5 electrode. The superior electrochemical performance can be ascribed to the successful incorporation of red P into the unique carbon matrix with large surface area and pore volume, interconnected porous structure, excellent electronic conductivity and superior structural stability.

In Situ Nanoreactors: Controllable Photoluminescent Carbon-Rich Polymer Nanodots Derived from Fatty Acid under Photoirradiation.

Amphiphilic nanoreactors have been recently used to fabricate photoluminescent carbon-rich polymer nanodots (PCPNs). However, the applications of PCPNs have been limited by their requirements for high temperature and toxic organic solvents or catalysts and the difficult control of their luminescent properties. Herein, a novel and facile strategy is reported for the synthesis of controllable PCPNs. This strategy involves the use of in situ vesicular nanoreactors under mild photoirradiation with fatty acid as the precursor. The conjugation degree of the uniformly sized PCPNs can be increased by extending photoreaction time, thus enabling the tuning of the optical properties of PCPNs. The PCPNs, which feature controllable and outstanding luminescent properties, low cytotoxicity, and biocompatibility, are successfully applied in bioimaging and as fluorescent ink. The present strategy is an attractive and facile platform for the preparation of carbon-rich nanomaterials with controllable photoluminescence.

Vertically Oriented Graphene Nanoribbon Fibers for High-Volumetric Energy Density All-Solid-State Asymmetric Supercapacitors.

Graphene fiber based micro-supercapacitors (GF micro-SCs) have attracted great attention for their potential applications in portable and wearable electronics. However, due to strong π-π stacking of nanosheets for graphene fibers, the limited ion accessible surface area and slow ion diffusion rate leads to low specific capacitance and poor rate performance. Here, the authors report a strategy for the synthesis of a vertically oriented graphene nanoribbon fiber with highly exposed surface area through confined-hydrothermal treatment of interconnected graphene oxide nanoribbons and consequent laser irradiation process. As a result, the as-obtained fiber shows high length specific capacitance of 3.2 mF cm-1 and volumetric capacitance of 234.8 F cm-3 at 2 mV s-1 , as well as excellent rate capability and outstanding cycling performance (96% capacitance retention after 10 000 cycles). Moreover, an all-solid-state asymmetric supercapacitor based on graphene nanoribbon fiber as negative electrode and MnO2 coated graphene ribbon fiber as positive electrode, shows high volumetric capacitance and energy density of 12.8 F cm-3 and 5.7 mWh cm-3 (normalized to the device volume), respectively, much higher than those of previously reported GF micro-SCs, as well as a long cycle life with 88% of capacitance retention after 10 000 cycles.

High Volumetric Energy Density Asymmetric Supercapacitors Based on Well-Balanced Graphene and Graphene-MnO2 Electrodes with Densely Stacked Architectures.

The well-matched electrochemical parameters of positive and negative electrodes, such as specific capacitance, rate performance, and cycling stability, are important for obtaining high-performance asymmetric supercapacitors. Herein, a facile and cost-effective strategy is demonstrated for the fabrication of 3D densely stacked graphene (DSG) and graphene-MnO2 (G-MnO2 ) architectures as the electrode materials for asymmetric supercapacitors (ASCs) by using MnO2 -intercalated graphite oxide (GO-MnO2 ) as the precursor. DSG has a stacked graphene structure with continuous ion transport network in-between the sheets, resulting in a high volumetric capacitance of 366 F cm-3 , almost 2.5 times than that of reduced graphene oxide, as well as long cycle life (93% capacitance retention after 10 000 cycles). More importantly, almost similar electrochemical properties, such as specific capacitance, rate performance, and cycling stability, are obtained for DSG as the negative electrode and G-MnO2 as the positive electrode. As a result, the assembled ASC delivers both ultrahigh gravimetric and volumetric energy densities of 62.4 Wh kg-1 and 54.4 Wh L-1 (based on total volume of two electrodes) in 1 m Na2 SO4 aqueous electrolyte, respectively, much higher than most of previously reported ASCs in aqueous electrolytes.

Schottky Junction and D-A1 -A2 System Dual Regulation of Covalent Triazine Frameworks for Highly Efficient CO2 Photoreduction.

Covalent triazine frameworks (CTFs) are emerging as a promising molecular platform for photocatalysis. Nevertheless, the construction of highly effective charge transfer pathways in CTFs for oriented delivery of photoexcited electrons to enhance photocatalytic performance remains highly challenging. Herein, a molecular engineering strategy is presented to achieve highly efficient charge separation and transport in both the lateral and vertical directions for solar-to-formate conversion. Specifically, a large π-delocalized and π-stacked Schottky junction (Ru-Th-CTF/RGO) that synergistically knits a rebuilt extended π-delocalized network of the D-A1 -A2 system (multiple donor or acceptor units, Ru-Th-CTF) with reduced graphene oxide (RGO) is developed. It is verified that the single-site Ru units in Ru-Th-CTF/RGO act as effective secondary electron acceptors in the lateral direction for multistage charge separation/transport. Simultaneously, the π-stacked and covalently bonded graphene is regarded as a hole extraction layer, accelerating the separation/transport of the photogenerated charges in the vertical direction over the Ru-Th-CTF/RGO Schottky junction with full use of photogenerated electrons for the reduction reaction. Thus, the obtained photocatalyst has an excellent CO2 -to-formate conversion rate (≈11050 µmol g-1 h-1 ) and selectivity (≈99%), producing a state-of-the-art catalyst for the heterogeneous conversion of CO2 to formate without an extra photosensitizer.

Metal-organic framework-mediated construction of confined ultrafine nickel phosphide immobilized in reduced graphene oxide with excellent cycle stability for asymmetric supercapacitors.

Transition metal phosphides (TMPs) with unique metalloid features have been promised great application potential in developing high-efficiency electrode materials for electrochemical energy storage. Nevertheless, sluggish ion transportation and poor cycling stability are the critical hurdles limiting their application prospects. Herein, we presented the metal-organic framework-mediated construction of ultrafine Ni2P immobilized in reduced graphene oxide (rGO). Nano-porous two-dimensional (2D) Ni-metal-organic framework (Ni-MOF) was grown on holey graphene oxide (Ni(BDC)-HGO), followed by MOF-mediated tandem pyrolysis (carbonization and phosphidation; Ni(BDC)-HGO-X-P, X denoted carbonization temperature and P represented phosphidation). Structural analysis revealed that the open-framework structure in Ni(BDC)-HGO-X-Ps had endowed them with excellent ion conductivity. The Ni2P wrapped by carbon shells and the PO bonds linking between Ni2P and rGO ensured the better structural stability of Ni(BDC)-HGO-X-Ps. The resulting Ni(BDC)-HGO-400-P delivered a capacitance of 2333.3 F g-1 at 1 A g-1 in a 6 M KOH aqueous electrolyte. More importantly, Ni(BDC)-HGO-400-P//activated carbon, the assembled asymmetric supercapacitor with an energy density of 64.5 Wh kg-1 and a power density of 31.7 kW kg-1, almost maintained its initial capacitance after 10,000 cycles. Furthermore, in situ electrochemical-Raman measurements were exploited to demonstrate the electrochemical changes of Ni(BDC)-HGO-400-P throughout the charging and discharging processes. This study has further shed light on the design rationality of TMPs for optimizing supercapacitor performance.

Bioinspired design of Na-ion conduction channels in covalent organic frameworks for quasi-solid-state sodium batteries.

Solid polymer electrolytes are considered among the most promising candidates for developing practical solid-state sodium batteries. However, moderate ionic conductivity and narrow electrochemical windows hinder their further application. Herein, inspired by the Na+/K+ conduction in biological membranes, we report a (-COO-)-modified covalent organic framework (COF) as a Na-ion quasi-solid-state electrolyte with sub-nanometre-sized Na+ transport zones (6.7-11.6 Å) created by adjacent -COO- groups and COF inwalls. The quasi-solid-state electrolyte enables selective Na+ transport along specific areas that are electronegative with sub-nanometre dimensions, resulting in a Na+ conductivity of 1.30×10-4 S cm-1 and oxidative stability of up to 5.32 V (versus Na+/Na) at 25 ± 1 °C. Testing the quasi-solid-state electrolyte in Na||Na3V2(PO4)3 coin cell configuration demonstrates fast reaction dynamics, low polarization voltages, and a stable cycling performance over 1000 cycles at 60 mA g-1 and 25 ± 1 °C with a 0.0048% capacity decay per cycle and a final discharge capacity of 83.5 mAh g-1.

A Nanostructured Moisture-Absorbing Gel for Fast and Large-Scale Passive Dehumidification.

Dehumidification is significant for environmental sustainability and human health. Traditional dehumidification methods involve significant energy consumption and have negative impact on the environment. The core challenge is to expose hygroscopic surfaces to the air, and appropriately store the captured water and avoid surface inactivation. Here, a nanostructured moisture-absorbing gel (N-MAG) for passive dehumidification, which consists of a hydrophilic nanocellulose network functionalized by hygroscopic lithium chloride, is reported. The interconnected nanocellulose can transfer the captured water to the internal space of the bulky N-MAG, eliminating water accumulation near the surfaces and hence enabling high-rate moisture absorption. The N-MAG can reduce the relative humidity from 96.7% to 28.7% in 6 h, even if the space is over 2 × 104 times of its own volume. The condensed water can be completely confined in the N-MAG, overcoming the problem of environmental pollution. This research brings a new perspective for sustainable humidity management without energy consumption and with positive environmental footprint.

Atomically Interfacial Engineering on Molybdenum Nitride Quantum Dots Decorated N-doped Graphene for High-Rate and Stable Alkaline Hydrogen Production.

The development of low-cost, high-efficiency, and stable electrocatalysts for hydrogen evolution reaction (HER) under alkaline conditions is a key challenge in water electrolysis. Here, an interfacial engineering strategy that is capable of simultaneously regulating nanoscale structure, electronic structure, and interfacial structure of Mo2 N quantum dots decorated on conductive N-doped graphene via codoping single-atom Al and O (denoted as AlO@Mo2 N-NrGO) is reported. The conversion of Anderson polyoxometalates anion cluster ([AlMo6 O24 H6 ]3- , denoted as AlMo6) to Mo2 N quantum dots not only result in the generation of more exposed active sites but also in situ codoping atomically dispersed Al and O, that can fine-tune the electronic structure of Mo2 N. It is also identified that the surface reconstruction of AlOH hydrates in AlO@Mo2 N quantum dots plays an essential role in enhancing hydrophilicity and lowering the energy barriers for water dissociation and hydrogen desorption, resulting in a remarkable alkaline HER performance, even better than the commercial 20% Pt/C. Moreover, the strong interfacial interaction (MoN bonds) between AlO@Mo2 N and N-doped graphene can significantly improve electron transfer efficiency and interfacial stability. As a result, outstanding stability over 300 h at a current density higher than 100 mA cm-2 is achieved, demonstrating great potential for the practical application of this catalyst.

Template-directed synthesis of pomegranate-shaped zinc oxide@zeolitic imidazolate framework for visible light photocatalytic degradation of tetracycline.

The development of photocatalysts for efficient tetracycline (TC) degradation under visible light is urgently needed yet remains a great challenge. Most semiconductor photocatalysts with low specific surface area are easy to agglomerate in solution and unfavorable for enriching pollutants. Herein, we present the preparation of pomegranate-shaped zinc oxide@zeolitic imidazolate framework (ZnO@ZIF-8) by in situ growth of ZIF-8 on a petal-shaped ZnO template that enhances the adsorption and photocatalytic degradation of TC. ZnO@ZIF-8 exhibits an excellent photostability and a TC photodegradation efficiency of 91% under visible light (λ > 420 nm) in 50 min at room temperature, which can be recycled over five times without any loss of activity. Moreover, the plausible photocatalysis reaction mechanism and the degradation intermediates are elucidated with the aid of three-dimensional excitation-emission matrix spectra and liquid chromatography-mass spectrometry system. This study offers new insights into the design of antibiotic degradation photocatalysts and the development of photocatalysts with broad-spectrum responses for efficient TC elimination.

Recent Developments of Transition Metal Compounds-Carbon Hybrid Electrodes for High Energy/Power Supercapacitors.

Due to their rapid power delivery, fast charging, and long cycle life, supercapacitors have become an important energy storage technology recently. However, to meet the continuously increasing demands in the fields of portable electronics, transportation, and future robotic technologies, supercapacitors with higher energy densities without sacrificing high power densities and cycle stabilities are still challenged. Transition metal compounds (TMCs) possessing high theoretical capacitance are always used as electrode materials to improve the energy densities of supercapacitors. However, the power densities and cycle lives of such TMCs-based electrodes are still inferior due to their low intrinsic conductivity and large volume expansion during the charge/discharge process, which greatly impede their large-scale applications. Most recently, the ideal integrating of TMCs and conductive carbon skeletons is considered as an effective solution to solve the above challenges. Herein, we summarize the recent developments of TMCs/carbon hybrid electrodes which exhibit both high energy/power densities from the aspects of structural design strategies, including conductive carbon skeleton, interface engineering, and electronic structure. Furthermore, the remaining challenges and future perspectives are also highlighted so as to provide strategies for the high energy/power TMCs/carbon-based supercapacitors.

Wood-Derived Carbon with Selectively Introduced C═O Groups toward Stable and High Capacity Anodes for Sodium Storage.

Biomass-derived carbon is a promising sustainable anode material for sodium-ion batteries (SIBs). Although the electrochemical performance can be improved by introducing functional groups, the selective introduction of single functional groups into biomass carbon remains difficult. Here, we overcome this challenge by developing a wood-derived carbon with selectively introduced C═O groups by combining tetramethoxysilane (TMOS) with wood cellulose pulps. The integration of TMOS introduces abundant C═O groups into the carbon during the polycondensation and pyrolysis process. The C═O groups play a dominant role in anode surface-controlled processes, and this leads to improvements in pseudo-capacity and fast electrode process kinetics. Besides, the introduction of C═O groups generates oxygen functional active sites that promote Na+ adsorption and creates a sufficiently large graphene interlayer distance. The as-obtained carbon shows a high capacity of 330 mAh g-1 at 40 mA g-1 and excellent cycling stability. Moreover, our strategy is simple and uses wood cellulose pulps as precursors. It therefore enables low-cost and large-scale synthesis of carbon anode materials for SIBs.

Sandwiching Sulfur into the Dents Between N, O Co-Doped Graphene Layered Blocks with Strong Physicochemical Confinements for Stable and High-Rate Li-S Batteries.

The development of lithium-sulfur batteries (LSBs) is restricted by their poor cycle stability and rate performance due to the low conductivity of sulfur and severe shuttle effect. Herein, an N, O co-doped graphene layered block (NOGB) with many dents on the graphene sheets is designed as effective sulfur host for high-performance LSBs. The sulfur platelets are physically confined into the dents and closely contacted with the graphene scaffold, ensuring structural stability and high conductivity. The highly doped N and O atoms can prevent the shuttle effect of sulfur species by strong chemical adsorption. Moreover, the micropores on the graphene sheets enable fast Li+ transport through the blocks. As a result, the obtained NOGB/S composite with 76 wt% sulfur content shows a high capacity of 1413 mAh g-1 at 0.1 C, good rate performance of 433 mAh g-1 at 10 C, and remarkable stability with 526 mAh g-1 at after 1000 cycles at 1 C (average decay rate: 0.038% per cycle). Our design provides a comprehensive route for simultaneously improving the conductivity, ion transport kinetics, and preventing the shuttle effect in LSBs.

3D Carbon Frameworks for Ultrafast Charge/Discharge Rate Supercapacitors with High Energy-Power Density.

Carbon-based electric double layer capacitors (EDLCs) hold tremendous potentials due to their high-power performance and excellent cycle stability. However, the practical use of EDLCs is limited by the low energy density in aqueous electrolyte and sluggish diffusion kinetics in organic or/and ionic liquids electrolyte. Herein, 3D carbon frameworks (3DCFs) constructed by interconnected nanocages (10-20 nm) with an ultrathin wall of ca. 2 nm have been fabricated, which possess high specific surface area, hierarchical porosity and good conductive network. After deoxidization, the deoxidized 3DCF (3DCF-DO) exhibits a record low IR drop of 0.064 V at 100 A g-1 and ultrafast charge/discharge rate up to 10 V s-1. The related device can be charged up to 77.4% of its maximum capacitance in 0.65 s at 100 A g-1 in 6 M KOH. It has been found that the 3DCF-DO has a great affinity to EMIMBF4, resulting in a high specific capacitance of 174 F g-1 at 1 A g-1, and a high energy density of 34 Wh kg-1 at an ultrahigh power density of 150 kW kg-1 at 4 V after a fast charge in 1.11 s. This work provides a facile fabrication of novel 3D carbon frameworks for supercapacitors with ultrafast charge/discharge rate and high energy-power density.