Search

In recent years, paper‐based functional materials have received extensive attention in the field of energy storage due to their advantages of rich and adjustable porous network structure and good flexibility. As an important energy storage device, paper‐based supercapacitors have important application prospects in many fields and have also received extensive attention from researchers in recent years. At present, researchers have modified and regulated paper‐based materials by different means such as structural design and material composition to enhance their electrochemical storage capacity. The development of paper‐based supercapacitors provides an important direction for the development of green and sustainable energy. Therefore, it is of great significance to summarize the relevant work of paper‐based supercapacitors for their rapid development and application. In this review, the recent research progress of paper‐based supercapacitors based on cellulose was summarized in terms of various cellulose‐based composites, preparation skills, and electrochemical performance. Finally, some opinions on the problems in the development of this field and the future development trend were proposed. It is hoped that this review can provide valuable references and ideas for the rapid development of paper‐based energy storage devices. [ABSTRACT FROM AUTHOR]

Due to their rich and adjustable porous network structure, paper-based functional materials have become a research hotspot in the field of energy storage. However, reasonably designing and making full use of the rich pore structure of paper-based materials to improve the electrochemical performance of paper-based energy storage devices still faces many challenges. Herein, we propose a structure engineering technique to develop a conductive integrated gradient porous paper-based (CIGPP) supercapacitor, and the kinetics process for the influence of gradient holes on the electrochemical performance of the CIGPP is investigated through experimental tests and COMSOL simulations. All results indicate that the gradient holes endow the CIGPP with an enhanced electrochemical performance. Specifically, the CIGPP shows a significant improvement in the specific capacitance, displays rich frequency response characteristics for electrolyte ions, and exhibits a good rate performance. Also, the CIGPP supercapacitor exhibits a low self-discharge and maintains a stable electrochemical performance in different electrolyte environments because of gradient holes. More importantly, when the CIGPP is used as a substrate to fabricate a CIGPP-PANI hybrid, it still maintains good electrochemical properties. In addition, the CIGPP supercapacitor also shows excellent stability and sensitivity for monitoring human motion and deaf-mute voicing, showing potential application prospects. This study provides a reference and feasible way for the design of structure-engineered integrated paper-based energy storage devices with outstanding comprehensive electrochemical performance. [ABSTRACT FROM AUTHOR]

Recently, with the continuous development of human society and the continuous innovation of technologies, the intelligence era has arrived. Various intelligent electronic devices continue to be developed, in which flexible wearable electronic devices are highly favored by people. To meet the requirements of the normal operation of intelligent devices, the key point lies in the development of new smart energy storage devices. Accordingly, smart supercapacitors have been widely focused on and studied by researchers recently with the introduction of intelligent functions, such as electrochromism, self‐healing, and shape memory, into supercapacitors to broaden their application fields and promote their smart development. This can meet not only people's energy needs but also people's diverse personality needs and make our life more convenient, fast, and more intelligent than ever. Therefore, it is very important to summarize related work on smart supercapacitors. Although researchers have performed much research on smart supercapacitors, there is still little literature summary on the related work of different smart supercapacitors. Accordingly, this paper mainly introduces the research progress on electrochromic, self‐healing, shape memory, and self‐charging smart supercapacitors in recent years and discusses the development prospects and challenges of smart supercapacitors. [ABSTRACT FROM AUTHOR]

• A MOF@CNF/rGO-Vitrimer composite electrode was fabricated via a simple method. • The as-obtained supercapacitor shows a remarkable cycling stability of 97.42% after 20,000 cycles. • The introduction of Vitrimer endows the supercapacitor with shape-memory functionality. • This work provides new ideas for the customizable design of energy storage devices. With the rapid development of flexible electronic devices towards small, light, and high-performance, people's requirements for electrode materials that affect energy storage devices are also increasing. It is crucial to prepare composite electrode materials with excellent comprehensive performance through reasonable design. This study successfully prepared a novel Ni-metal-organic framework (Ni-MOF) @ cellulose nanofibers (CNF)/reduced graphene oxide (rGO) -Vitrimer (MOF@CNF/rGO-V) electrode material through freeze-drying and solvent-thermal methods. In the hybrid, CNF not only prevents the stacking of rGO but also serves as a flexible substrate for loading Ni-MOF, while the porous structure of the CNF aerogel provides numerous channels for electrolyte ions to store and transport. The presence of Ni-MOF loaded on the conductive substrate contributes to a high pseudo-capacitance, ultimately yielding a composite material with a high specific capacitance (189.9 F g −1). Furthermore, when the composite was assembled into a symmetric supercapacitor device, it exhibited an energy density of 35.61 W h kg−1 at a power density of 641.07 W kg−1 and a remarkable cycling stability of up to 96.59% after experiencing 20,000 cycles. In addition, the introduction of Vitrimer successfully prevented electrode material detachment or fracture during use while maintaining excellent electrochemical and mechanical properties, imparting shape-memory functionality. The as-fabricated MOF@CNF/rGO-V composite electrode material holds significant promise and attractiveness in the field of flexible wearable electronics. [Display omitted] [ABSTRACT FROM AUTHOR]

Cellulose nanofiber (CNF) materials have attracted increasing attention in the field of energy storage and sensing due to their flexibility, environmental protection and sustainability. However, CNF materials have poor conductivity and low utilization effciency, which limits their applications. Improving the conductivity and utilization efficiency of CNFs while retaining their advantages is of great significance for developing wide applications of biomass resources. In this work, noncarbonized CNF@graphene quantum dot (GQD) film with good flexibility was fabricated through a combination of electrolysis and liquid dispersion. The as-obtained hybrid film shows excellent electrochemical storage performance, mechanical properties and sensing characteristics. Specifically, the film presents a specific capacitance of 118 mF cm− 2 even at a ultrahigh scan rate of 1000 mV s− 1, and a high capacitance retention higher than 93% at different current densities after 5000 cycles. Additionally, the assembled supercapacitor based on the hybrid film possesses high power and energy density at the same time (782 mW cm− 2 and 596 µWh cm− 2). These results demonstrate that the hybrid film possesses excellent rate performance and cycle stability. In addition, the film is sensitive to movement of the human body. [ABSTRACT FROM AUTHOR]

In this work, a high-performance electrode material has been fabricated by the incorporation of carbon nanotubes (CNTs) and polyaniline (PANI) on a carbon foams (CF) to improve its electrochemical performance. The microstructure and performance of as-prepared material was characterized in detail. Results showed that the resultant material exhibited a high gravimetric capacitance up to 467.1 F g−1, higher energy density of 104. 2 Wh kg−1 and power density of 3000 W kg−1 at a current density 3 A g−1 when the electrochemical doping time of PANI equals to 20 min. Furthermore, it appeared a good cycling stability with capacitance retention of 94.5% after 10000 cycles. The enhanced electrochemical performance can be attributed to the unique carbon nanostructure and synergistic effects of active materials CNTs and PANI. It indicates that this novel CF/CNTs/PANI-20 composite is a promising candidate for electrochemical capacitors. [ABSTRACT FROM AUTHOR]

• Multi-functional cellulose-based hybrid with layered conductive network structure are fabricated. • TONF fibers intertwined to form a conductive layer provides a fast path for electron transfer and ion diffusion. • The hybrid exhibits a high specific capacitance and energy density. • The layered conductive network structure gives the hybrid excellent electromagnetic shielding properties. In this work, a conductive TEMPO-cellulose nanofibers(TONF)/conductive carbon black(CCB)/ Vinasse activated carbon(VAC)(TCA) composite was constructed by electrostatic adsorption, freeze-drying, and hot pressing. In this composite, a conductive TONF composite with good electrical conducting properties was constructed by electrostatic adsorption between TONF and CCB. And the conductive TONF can be used as an ideal dispersant to effectively prevent accumulation between VACs. In addition, TONF imparts TCA composites with excellent mechanical properties. Due to the layered conductive network structure formed by the effective tight stacking between the highly conductive TONF layer and the VAC, the assembled supercapacitor exhibits a high specific capacitance of 263F g−1 (672 mF cm−2), energy density of 23.8 Wh kg−1, and power density of 5.7 KW kg−1. What's more, the assembled supercapacitor can exhibit excellent cycle stability after 12,000 cycles. In addition, An intelligent electromagnetic(EMI) shielding TCA-V composite material with shape memory function was prepared by introducing a dynamically cross-linked polymer Vitrimer. In summary, TCA composites have excellent integration properties, especially electrochemical properties with good stability performance and excellent EMI shielding properties. These remarkable features make nano cellulose/carbon-matrix composites have great attraction and potential in the field of supercapacitors and intelligent EMI shielding. [ABSTRACT FROM AUTHOR]

In this paper, a facile method is designed to fabricate three-dimensional (3D) graphene (GR)/manganese dioxide (MnO2) nanowall electrode material. The 3D GR/MnO2 hybrid is prepared by a combination of electrochemical deposition (ELD) and electrophoresis deposition (EPD), followed by thermal reduction (TR). Firstly, the 3D graphene oxide (GO)/MnO2 hybrid is obtained by the ELD-EPD method. Secondly, the 3D GR/MnO2 hybrid is obtained through hydrogen reduction at a certain temperature. The as-fabricated hybrid has been characterized by scanning electron microscope (SEM), transmission electron microscope (TEM) and Raman spectroscopy. The electrochemical properties have been also measured by cyclic voltammetry. The results showed that the 3D GR/MnO2 nanowalls hybrid has a high specific capacitance of 266.75Fg and a high energy density of 25.36Whkg. Moreover, a high specific capacitance (240.15Fg) at a high scan rate of 200mVs (90% capacity retention) has been also obtained. Additionally, the hybrid can serve directly as the electrodes of supercapacitor without adding binder. This work provides a novel road to fabricate a binder-free 3D GR-based hybrid for high-performance energy storage devices. 3D RGO-MnO2 hybrid has been successfully obtained by a combination of electrochemical deposition and electrophoresis deposition, followed by thermal reduction. The as-prepared 3D RGO-MnO2 hybrid proved its potential applications in electrochemical supercapacitors, besides the facile method and controllable structure may provide its use in large scale production and application. [ABSTRACT FROM AUTHOR]

This paper describes the characterization of a three-dimensional (3D) reduced graphene oxide (RGO)-carbon nanotube (CNT)-polyaniline (PANI) hybrid fabricated by combining electrophoretic deposition (EPD) and floating catalyst chemical vapor deposition (FCCVD), followed by in - situ anodic electrochemical polymerization (AEP). Firstly, the RGO-CNT is prepared by combining EPD of GO onto nickel foams (NF) and then growth of uniformly aligned CNT on the surface of RGO via FCCVD. Secondly, the 3D RGO-CNT-PANI hybrid is successfully fabricated by in situ AEP of aniline monomers onto the surface of the RGO-CNT. The structures and morphologies of the hybrid have been characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy, X - ray diffraction (XRD) and X-ray photoelectron spectrometer (XPS). Electrochemical properties are studied by cyclic voltammetry, galvanostatic charge/discharge measurements, and electrochemical impedance spectroscopy. The results reveal that the as-prepared hybrid based on the two - electrode system displays very high specific capacitance of 741 F g −1 with a high energy density of 92.4 Wh kg −1 and high power density of 6.3 kW kg −1 at the scan rate of 10 mV s −1 . Additionally, the hybrid shows good cycling stability with a retention ratio of 95% after 5000 cycles. These attractive results suggest that this 3D RGO-CNT-PANI hybrid has a great potential as an electrode material for high performance supercapacitors. [ABSTRACT FROM AUTHOR]

As an environmentally friendly energy storage device, supercapacitors have the advantages of low pollution and fast charging and discharging speed, which have attracted extensive attention of researchers. Aerogels are considered as a potential electrode material for supercapacitors due to its excellent characteristics such as light weight, low density, porosity. In last decades, although researchers have done a lot of work in the field of aerogels as electrodes of supercapacitors, the updating speed of knowledge is faster and faster. In addition, electrolyte also has an important influence on the energy storage characteristics of supercapacitors. Therefore, this mini review paper aims to compare the influence of different electrolytes on the energy storage performance of supercapacitors and summarize the recent research on the application of aerogel electrodes in supercapacitors in the past three years, in terms of various aerogel electrodes, material structure design, preparation methods, and related electrochemical performance. Finally, in view of the existing problems and challenges in the field, the author also gives his own views and prospects. Hopefully, this mini review can provide some more comprehensive information and reference for the further development and exploration of various electrolyte and aerogel electrodes of supercapacitors with excellent comprehensive electrochemical performance. [Display omitted] • The recent research on various electrolyte and aerogel materials are summarized. • The advantages and disadvantages of different aerogel materials are analyzed. • Electrochemical performances of asymmetric supercapacitor are compared. • The outlook and opinions on the existing problems and challenges are given. [ABSTRACT FROM AUTHOR]

Due to its natural and rich porous structure, biomass wood-based materials have potential applications in electronic devices such as supercapacitors and sensors, which is also in line with the concept of green and sustainable development and has attracted extensive attention of more and more researchers. However, due to the poor conductivity of wood-based materials, in order to enhance their conductivity, they have to be carbonized or compounded with other materials with good conductivity. Here, we first synthesized the rGO-LiOH/wood micro-spring composite with high strength, high specific capacitance, high elasticity and elastic recovery rate via vacuum suction and carbonization. The as-obtained wood-based hybrid is applied to supercapacitors and sensors, and shows good supercapacitance and sensing characteristics. Under a scan rate of 200 mV s−1, the specific capacitance is 352 F g−1, the energy density is 48.89 Wh kg−1, the power density reaches 9780 W kg−1, and the capacitance retention still maintains at 98% (346 F g−1) after experiencing 1000 cycles, showing excellent energy storage and working stability. More importantly, the composite still shows stable energy storage effect under repeated compression rebound conditions. After 5000 compression-recovery, a high elastic recovery rate of 91.67% and high capacitance retention of approximately 80% are still obtained. These outstanding properties highlight the great application potential of the rGO-LiOH/wood micro-spring composite in biomass based wearable electronics, portable power supply equipment and sensors. [Display omitted] • A novel rGO-LiOH/wood micro-spring composite is fabricated. • The hybrid shows excellent capacitance retention and elastic recovery capacity. • The rGO-LiOH supports the arch structure of carbonized wood without being damaged. • Porous structure of wood provides channels for electrolyte ions to transfer. • More ways are explored for sustainable utilization of high value biomass resources. [ABSTRACT FROM AUTHOR]

[Display omitted] • Flower-like CoS, NiS nanofibers with Co, Ni nanoparticles hybrid was loaded into CLFW. • The obtained CLFW@(Co, Ni)-(CoS, NiS) hybrid shows good supercapacitive performance. • The natural porous structure of wood provides numerous electrolyte ions channels. • Cross-linked NiS, CoS nanofibers form new pores for transport of electrolyte ions. • Expect to provide more possible applications for renewable wood-based materials. A novel hybrid composed of carbonization lignin-free wood as an effective scaffold for loading CoS, NiS nanofibers with Co, Ni flower-like structure attached Co, Ni nanoparticles is fabricated as electrode material for high-performance supercapacitor. For the resultant, the natural porous pipe structure of wood provides a large number of electrolyte ions channels for the hybrid. The flower-like NiS, CoS distributed along the carbonized wood pipe gather together to form NiS nanofibers. These NiS and CoS nanofibers interweave with each other to form some new pores, which is helpful for the transport of electrolyte ions. As a result, the synergistic effect of these components endows the wood-based hybrid with good supercapacitive performance: high gravity (volumetric) energy densities of 46 Wh kg−1 (66 Wh L-1) are obtained, meanwhile sustaining high gravity (volumetric) power densities of 68 kW kg−1 (50 kW L-1). [ABSTRACT FROM AUTHOR]

[Display omitted] • A multifunctional CWCC-rGO@PVA wood based hybrid is successfully fabricated. • The hybrid possesses high flexibility and deformable properties. • The free protons from PVA endow the hybrid with humidity sensitive characteristics. • Porous wood provides space and channels for electrolyte ions to storage and transfer. • Explore more possibilities of sustainable utilization of biomass resources. Wood, as a kind of biomass material, has potential application value in many aspects. In this paper, we designed and prepared a carbonized wood cell chamber-reduced graphene oxide@PVA (CWCC-rGO@PVA) composite material with high specific capacitance, high flexibility, deformability and power generation ability from ambient water using carbonized wood cell chamber (CWCC) as the substrate. GO, as an intermediate product, binds with CWCC in the form of C–C bonds, and the as-obtained intermediate product CWCC-rGO combines with PVA to form hydrogen bonds. The resultant final hybrid CWCC-rGO@PVA shows outstanding electrochemical performance including a high specific capacitance of 288F g−1, capacitance retention of 91%, energy density of 36 Wh kg−1 and power density of 3600 W kg−1. In addition, PVA not only contributes to the high flexibility and deformability of the CWCC-rGO@PVA hybrid, but also has abundant free protons that endow the composite with sensitive sensing properties, so it can serve as a sensor to detect physiological signals of human movement. More importantly, the hydroxylates rich in CWCC-rGO-PVA form hydrogen bonds with the water in the ambient environment, generating a current of up to 5.7 μA under the action of the concentration gradient, which indicates that the CWCC-rGO@PVA can generate electricity by water. [ABSTRACT FROM AUTHOR]

As a kind of green renewable resource from trees, wood has abundant porous structure, which makes it have great potential in the field of energy storage. However, poor conductivity and limited energy storage capacity hinder the application of wood in the field of energy storage. Here, a novel carbonization lignin-free wood (CLFW)@Co-CoS hybrid is designed and fabricated by a combination of vacuum filtration and carbonization. The CLFW@Co-CoS hybrid assembled into wood-based supercapacitor presents a high areal energy density of 610 μWh cm−2, meanwhile maintaining a high areal power density of 192 mW cm−2. There are two main reasons for the excellent capacitance characteristics: one thing is that wood has a natural and abundant porous structure, which provides more space and channels for the storage and transport of electrolyte ions. The other thing is that CoS and Co can provide high capacitance, and numerous new pores are created by the interweaving of CoS nanofibers with flower-like structure. Additionally, Co nanoparticles attached to CoS and wood have more active sites, which endows the hybrid with excellent ORR properties. Thus, this bifunctional material with excellent electrochemical performance and outstanding ORR properties has huge potential in the field of energy storage and catalysis. Unlabelled Image • Co/CoS nanofibers immobilized in carbonization wood as bifunctional hybrid for supercapacitor and electrocatalyst. • The porous wood and the pores formed by cross-linked CoS nanofibers contribute a high areal power density of 192 mW cm−2. • The high capacitance provided by Co and CoS endows wood-based composites with a high areal energy density of 610 μWh cm−2. • The hybrid shows a high oxygen reduction reaction onset potential of 0.9 V, close to commercial Pt / C. [ABSTRACT FROM AUTHOR]

• A smart integrated bifunctional paper-based device is fabricated. • The paper device shows good reshaping, shape-memory and self-healing properties. • The supercapacitor with separator-free delivers high energy and power densities. • Introduction of vitrimer improves the cycle stability of the paper-based device. Smart devices based on paper-based composite materials are attracting increasing attention for applications in wearable and flexible energy storage and strain sensors, due to their outstanding flexibility and light weight properties. Although the paper materials are modified by various methods to overcome the shortcomings of poor conductivity and obtain various smart properties, the functionalized paper-based materials generally have poor swelling, mechanical strength and cycle stability in the electrochemical process, which seriously affects the application of paper-based devices in energy storage. Herein, for the first time a new class of symmetrical integrated smart paper-based supercapacitors with binder-free was fabricated by incorporating vitrimer (V) into original paper with pencil-drawing (OPD) loading polyaniline nanofibers (PN). The resultant OPD@PN-V supercapacitor show high gravimetric and areal specific energy density of 56 Wh kg−1 and 785 μWh cm−2 and simultaneously maintains high gravimetric and areal specific power density of 78 kW kg−1 and 286 mW cm−2, substantially surpassing the performance of conventional supercapacitors device with separator. More importantly, the introduction of vitrimer greatly enhances the cycle stability of the supercapacitor, and the supercapacitor also displays good reshaping, shape-memory and self-healing properties, which greatly broadens the application scenarios of supercapacitors. Besides, the OPD@PN-V device also shows a great potential in detecting the movement of human. [ABSTRACT FROM AUTHOR]

Recently, with the concept of building a resource-conserving and environment-friendly society, the idea of developing green, sustainable and multifunctional materials has become increasingly urgent. So, how to explore more possible ways for efficient and sustainable utilization of biomass resources is very important. In this paper, a novel eco-friendly and sustainable 3D bifunctional carbon microtubes@nitrogen-doped reduced graphene oxide (CMT@N-RGO) hybrid based biomass material is firstly fabricated by combining dipping and chemical vapor deposition methods. Then the CMT@N-RGO hybrid is served as an excellent carbonaceous scaffold for constructing hierarchical hybrid with high-performance in energy storage and electrocatalysis. Finally, we have successfully prepared CMT@N-RGO/MnO 2 and CMT@N-RGO/PANI hybrid with good supercapacitive and excellent oxygen reduction reaction (ORR). In short, the as-fabricated hybrid served as electrodes of supercapacitor present fast charge/discharge rate, excellent rate performance, and outstanding capacitance retention of 95% (93%) and high energy efficiency of 65–77% (61–72%) for both. In addition, the hybrid acted as an efficient electrocatalyst in the oxygen reduction reaction shows a larger positive onset potential of −0.12 V and half-wave potential of −0.21 V, which can be comparable to that of commercial Pt/C electrode. The improved capacitive and electrocatalytic properties are mainly attributed to the synergistic effects between the CMT and N-RGO/PANI (MnO 2). In a word, these attractive results demonstrate that the 3D CMT@N-RGO/PANI (MnO 2) hybrid are promising high-performance bifunctional material for supercapacitors and ORR catalyst. Hopefully, it can open up a versatile way for us to devise and manufacture more various multifunctional biomass-based material with outstanding electrochemical properties, excellent oxygen reduction reaction performance and other outstanding properties. Image 1 • CMT@N-RGO hybrid presents fast charge/discharge and high rate performance. • The cross-linked CMT can function as a bridge for the transmission of electrons. • N, PANI and MnO 2 can provide electrocatalysts and pseudocapacitance performance. • The fabricated hybrid show good bifunctional properties for supercapacitor and ORR. • Explore more possible ways for sustainable utilization of biomass resources. [ABSTRACT FROM AUTHOR]

A highly conductive and flexible composite film of Poly (3,4-ethylenedioxythiophene):polystyrene sulfonate and aramid nanofiber (PEDOT:PSS/ANFs) is prepared by vacuum-assisted filtration and post-treated by acid. The composite displays excellent mechanical integrity under bending together with flexibility, properties being attributed to the strong attachment of PEDOT:PSS onto the surface of the ANFs via hydrogen bonding and the ANF structure, respectively. The conductivity of the prepared composite is progressively enhanced by the post-treatment using sulfuric acids (1 M H 2 SO 4 and 1.5 M H 2 SO 4), reaching 20–25 times higher than that of untreated film. This enhancement is traced to the removal of the insulating PSS group together with an analyzable change in crystallization of the PEDOT:PSS component. However, excessive use of acid treatment is seen to reduce the mechanical strength, and, thus, ultimate loss of conductivity after frequent bending (up to 1000 times), only having 59% conductivity retention with high concentration acid treatment (1.5 M H 2 SO 4) compared to a high conductivity retention of 95% with 1.0 M H 2 SO 4. Adopting the relatively weaker acid enables a balance to be reached between these crucial factors of electrical conductivity versus mechanical integrity. The prepared film of PEDOT: PSS/ANFs treated by acid as an electrode of supercapacitor shows good electrochemical performances, including good volumetric specific capacitance (83.5 F/cm3 with 1.0 M H 2 SO 4 and 75 F/cm3 with 1.5 M H 2 SO 4 at 0.5 A/cm−3), cycle stability and capacitance retention of 83.3% and 87.5% after 2000 cycles, respectively. Furthermore, a solid flexible supercapacitor is finally assembled by the post-treatment of relatively low concentration acid with 1.0 M H 2 SO 4. The configured supercapacitor displays excellent volumetric energy density of 23.44 mW h/cm2 (power density of 399.95 mW/cm2) at a very wide operating potential window of 0–1.6 V and cycle stability. Therefore, it is quite feasible method to fabricate a highly conductive and flexible composite film using PEDOT:PSS and ANFs by vacuum filtration and acid post-treatment, which expects to be a promising flexible composite electrode material applied in the preparation of energy storage devices. • A highly conductive and flexible composite film of PEDOT:PSS/ANFs is fabricated. • PEDOT:PSS onto the surface of ANFs via hydrogen bonding is disclosed. • The conductivity of the prepared film is enhanced by acid post-treatment. • The influence on mechanical strength is discussed when applying acid post-treatment. • The electrochemical performance of PEDOT:PSS/ANFs film is explored and discussed. [ABSTRACT FROM AUTHOR]

The optimization of the electrodes structure is crucial for supercapacitors. Herein, we report a novel three-dimensional (3D) hierarchical multihole architecture of ternary reduced graphene oxide (rGO)/MnO 2 /carbon foam (CF) nanocomposites. Thereinto, CF not only firstly serves as conductive skeleton but also offers primary pore structure with nickel foam and supporter for electrochemical deposition (ECD) of MnO 2 . Furthermore, rGO covered on electrodes surface both prevents the exfoliation of MnO 2 and integrates with it to construct secondary pore structure. The configuration with three components synergistic effects leads to a high specific capacitance of 356.5 F g −1 at a scan rate of 10 mV s −1 and a long cycle life along with 93.6% specific capacitance retained after 2000 cycles. Also, it even remained 30.6 Wh kg −1 at a large power density of 13.5 kW kg −1 . [ABSTRACT FROM AUTHOR]

Three-dimensional (3-D) graphene foam/PANI nanorods were fabricated by hydrothermal treatment of graphene oxide (GO) solution and sequentially in-situ synthesis of PANI nanorods on the surface of graphene hydrogel. 3-D graphene foam was used as substrate for the growth of PANI nanorods and it increases the specific surface area as well as the double layer capacitance performance of the graphene foam/PANI nanorod composite. The length of the PANI nanorod is about 340 nm . PANI nanorods exhibited a short stick shape. These PANI nanorods agglomerate together and the growth orientation is anisotropic. The highest specific capacitance of 3-D graphene/PANI nanorod composite electrodes is 352 F g −1 at the scan rate of 10 mV s −1 . [ABSTRACT FROM AUTHOR]