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Highly flexible, transparent, and conductive polytetrafluoroethylene (PTFE)/AgPdCu (APC)/indium zinc oxide (IZO) hybrid films are developed for use in transparent and flexible thin‐film heaters (FTFHs) integrated into electric vehicles. By controlling the thickness of each layer, PTFE/APC/IZO multilayer electrodes with a low sheet resistance of 9.73 Ω/sq and high transmittance of 80.08% at a wavelength of 550 nm and outstanding mechanical flexibility even though it is prepared at room temperature is obtained. In multilayer electrodes, each component plays a specific role, this is, IZO acts as a transparent barrier, APC is the main conduction path, and PTFE is the adhesive layer. Notably, the optimal PTFE/APC/IZO multilayer exhibited superior mechanical flexibility compared with that of the IZO/Ag/IZO multilayer owing to the soft PTFE adhesive layer. The FTFH with the optimized PTFE/APC/IZO multilayer demonstrated a high saturation temperature of 101.9 °C at a low input voltage of 12 V owing to the low sheet resistance and stability provided by the IZO barrier layer. Therefore, the PTFE/APC/IZO hybrid electrodes prepared via a continuous sputtering process provide an effective strategy for achieving high‐performance transparent FTFHs for next‐generation electric vehicles. [ABSTRACT FROM AUTHOR]

To realize flexible and wearable electronic devices in the future, it is important to develop flexible transparent electrodes while replacing indium tin oxide‐based transparent electrodes. Herein, a highly conductive transparent electrode based on hybrid materials of MXene nanosheet films and Ag nanowires (AgNWs) is reported, which synergistically combines the advantageous properties of each material. MXene/AgNW/colorless polyimide (cPI) hybrid electrode is prepared utilizing reverse sequential processing of MXene nanosheets and AgNWs and exhibits significantly improved conductivity and transmittance compared with the MXene/cPI electrode. Furthermore, owing to the abundant hydrophilic termination groups (‐O and ‐OH) on the MXene surface, the MXene/AgNW/cPI hybrid electrode shows hydrophilic surface properties and a highly uniform film. Therefore, the MXene/AgNW/cPI hybrid electrode exhibits higher transmittance at 550 nm to 79% than MXene/cPI electrode (59%) and considerably lower sheet resistance (13.08 ohm sq−1) than MXene/cPI electrode (113.6 ohm sq−1). Flexible organic photovoltaic devices fabricated with MXene/AgNW/cPI hybrid electrode achieve higher power conversion efficiency of 10.3% compared with 6.70% of the corresponding MXene/cPI electrode. These results provide the great potential of Ti3C2‐based MXene hybrid electrode as a flexible transparent electrode, paving the way for various and wider range of applications include solar cells and light‐emitting diodes. [ABSTRACT FROM AUTHOR]

Aqueous rechargeable zinc‐ion batteries (ARZBs) are intriguing for electrochemical energy storage applications because of their safety and cost‐effectiveness. Regarding cathode materials, rapid development has been observed with the organic‐based cathode materials that offer much higher structural integrity upon successive (de‐)insertion of charge carries ions. Even though promising results demonstrated with organic electrodes, they still suffer from the short cycle‐life due to their discharge products solubility in electrolyte. Herein, electrochemical performance and charge storage mechanism of the synthesized polyphosphazene‐based inorganic‐organic hybrid electrode containing pyrene‐4,5,9,10‐tetraone (PTO) redox active lateral group, poly[(bis(2‐amino‐4,5,9,10‐pyrenetetraone)], abbreviated as (PPAPT), were investigated in ARZBs. The charge storage mechanism of PPAPT was examined by various ex‐situ [Fourier transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD), scanning electron microscopy and energy dispersive X‐ray spectroscopy (SEM‐EDS), X‐ray photoelectron spectroscopy (XPS)] and in‐situ [pH change with bromocresol green indicator and electrochemical quartz crystal microbalance (EQCM)] characterization techniques as well as computational density functional theory (DFT) revealing that the PPAPT electrode (de‐)coordinates both zinc and proton. The electrode and its discharge product are insoluble in the electrolyte demonstrated by UV‐vis analysis and exhibited a stable cycling performance with a discharge capacity of 125.4 mAh g−1 after 1000 cycles at a current density of 10 C. [ABSTRACT FROM AUTHOR]

Recently metal‐organic framework (MOF) derived electrode materials have grown considerable research interest in the field of supercapacitor (SC) technology. Herein, MOF‐derived Zr‐Mn‐oxide is successively combined with solution‐free CuO nanowires not only to avoid the structural limitations of MOF but also to fabricate a positive‐negative hybrid electrode material. The MOF‐derived mixed metal oxide prepared through in situ fabrication allows the uniform and unidirectional growth of oriented Zr‐Mn‐oxide@CuO@Cu. The hybrid electrode exhibited over 100% stability after 20,000 cycles in a three‐electrode setup with a wide potential window range of 1.2 V (−0.6 to 0.6 V). Further, the obtained Zr‐Mn‐oxide@CuO@Cu hybrid electrode exhibited 14.1‐ and 5.5‐fold higher capacity over its MOF‐derived Zr‐Mn‐oxide counterpart (−0.6 to 0.1 V) and CuO (0.0 to 0.5 V), respectively. Additionally, the hybrid device with hybrid Zr‐Mn‐oxide@CuO@Cu as the positive electrode and reduced graphene oxide as the negative electrode also displayed promising energy and power densities. Furthermore, density functional theory calculations are employed to study the hybrid electrode material's properties. Overall, the unidirectional and vertically aligned MOF‐derived Zr‐Mn‐oxide@CuO@Cu hybrid electrode material with notable electrochemical performance can be useful for the fabrication of next‐generation supercapacitor electrodes. [ABSTRACT FROM AUTHOR]

Photorechargeable supercapacitors are perfect energy storage devices, particularly for solar cells that output electricity only during sunshine hours. The lower energy density of supercapacitors is due to fewer redox‐active sites, poor electrolyte accessibility at the electrodes, and charge loss during charge transfer from solar cells to the supercapacitor. Here, an electrolyte‐accessible organic–inorganic hybrid electrode with synergistic pseudocapacitance of Ti3C2Tx and high theoretical specific capacity CO active centers to enhance the energy density of the supercapacitor is proposed. Density functional theory (DFT) calculations show that the covalent cross‐linking of organic molecules changes the charge density redistribution of Ti3C2Tx, enhances ion absorption and storage, and increases the energy density of the supercapacitors. Based on these DFT calculation results, hybrid electrodes are successfully prepared using p‐phenylene diisocyanate to covalently cross‐link pseudocapacitors Ti3C2Tx with anthraquinone such as 1‐hydroxyanthraquinone (HA) or 1‐amino‐4‐bromoanthraquinone‐2‐sodium sulfonate (ABS). The Ti3C2Tx‐HA hybrid electrodes exhibit high areal specific capacity (2532.5 mF cm−2), excellent ion absorption storage capability, and long‐term stability. The asymmetric supercapacitor yields a decent area specific capacity (1686.72 mF cm−2 at 0.25 mA cm−2) and energy density (599.72 mWh cm−2 at a power density of 200 mW cm−2). These high‐energy‐density supercapacitors are coupled with perovskite solar cells to prepare photorechargeable supercapacitors with fast energy storage. [ABSTRACT FROM AUTHOR]

Intrinsically stretchable organic photovoltaics (is-OPVs) hold significant promise for integration into self-powered wearable electronics. However, their potential is hindered by the lack of sufficient consistency between optoelectronic and mechanical properties. This is primarily due to the limited availability of stretchable transparent electrodes (STEs) that possess both high conductivity and stretchability. Here, a hybrid STE with exceptional conductivity, stretchability, and thermal stability is presented. Specifically, STEs are composed of the modified PH1000 (referred to as S-PH1000) and silver nanowires (AgNWs). The S-PH1000 endows the STE with good stretchability and smoothens the surface, while the AgNWs enhance the charge transport. The resulting hybrid STEs enable is-OPVs to a remarkable power conversion efficiency (PCE) of 16.32%, positioning them among the top-performing is-OPVs. With 10% elastomer, the devices retain 82% of the initial PCE after 500 cycles at 20% strain. Additionally, OPVs equipped with these STEs exhibit superior thermal stability compared to those using indium tin oxide electrodes, maintaining 75% of the initial PCE after annealing at 85 °C for 390 h. The findings underscore the suitability of the designed hybrid electrodes for efficient and stable is-OPVs, offering a promising avenue for the future application of OPVs., (© 2024 Wiley‐VCH GmbH.)

Currently, hybrid composites are considered promising materials in energy applications. Among various approaches for synthesizing hybrid composites, the solution combustion approach has attracted significant research interest worldwide due to its high versatility, efficiency, simplicity, scalability, reproducibility, and cost-effectiveness. Further, solution combustion synthetic techniques have recently been regarded as one of the more facile methods for developing effective supercapacitor electrodes. This paper provides the synthesis of vanadium pentoxide (V2O5), nickel oxide-vanadium pentoxide (NiO/ V2O5), and nickel oxide-vanadium pentoxide-Graphene (NiO/ V2O5@Graphene) nano-composites using solution combustion method. The importance of the hybridization of transition metal oxide with other-transition metal oxide and carbon derivatives is studied systematically. The obtained materials are characterized by X-ray diffraction, UV-Visible spectroscopy, Fourier transform infrared spectroscopy, Field emission scanning electron microscopy, Energy-dispersive X-ray analysis, Cyclic voltammetric analysis, Galvanostatic charge-discharge, and Electrochemical impedance. The average crystalline sizes are calculated as 27 nm, 24 nm, and 14 nm for V2O5, NiO/ V2O5, and NiO/ V2O5@Graphene nano-composites. The UV-Visible, Fourier transform infrared, and Energy-dispersive X-ray spectroscopy analysis confirms the formation of synthesized materials. Field emission scanning electron microscopy provides the distribution of NiO/ V2O5 nano-composite over the graphene sheet. The electrochemical performance of V2O5 is improved drastically with the simultaneous hybridization of two metal oxides. Further, the addition of graphene makes a small enhancement in the specific capacitance of the nano-composites. The order of specific capacitance is V2O5 (328 F/g) ˂ NiO/V2O5 (918 F/g) ˂ NiO/V2O5@Graphene (939 F/g). The solution resistance and charge transfer resistance of the modified electrodes are in the order of V2O5 (1.59 Ω) ˃ NiO/V2O5 (0.85 Ω) ˃ NiO/V2O5@Graphene (0.73 Ω) and V2O5 (5.66 Ω) ˃ NiO/V2O5 (1.35 Ω) ˃ NiO/V2O5@Graphene (0.17 Ω) respectively, which supports the enhancement in specific capacitance upon hybridization. The obtained materials are cost-effective, low-toxic, and efficient, hence would be appropriate for industrial use.

Metal‐mesh transparent conductive electrodes (TCEs)‐based flexible perovskite solar cells (FPSCs) have been intensively explored to improve the efficiency and stability of the devices, whereas undesired metal‐induced decomposition of perovskite during film formation process could undermine the performance and stability of device. In this work, the authors construct a novel flexible hybrid electrode combining silver (Ag) mesh‐embedded poly(ethylene terephthalate) film (PET/Ag‐mesh) with a thin indium tin oxide (ITO) layer, named PET/Ag‐mesh/ITO, which exhibits outstanding photoelectric properties, chemical stability, and mechanical durability. They introduce the thin ITO film as a barrier layer to protect perovskite from the metal‐induced degradation. In comparison, the PET/Ag‐mesh/ITO based FPSCs achieve an optimized power conversion efficiency (PCE) of 18.10%, which is among the highest reported values for metal‐mesh based FPSCs to date. Owing to the excellent properties of PET/Ag‐mesh/ITO, the corresponding FPSCs demonstrate extraordinary mechanical and thermal stability, which is comparable to that of their rigid ITO‐based counterparts. [ABSTRACT FROM AUTHOR]

Present work describes the superficial incorporation of the RuO2 in pristine PPy matrix by simply immersing the pristine PPy FE in 20 ml of 1 μM aqueous solution of RuCl3 to soak it in PPy matrix followed by drying. XRD shows mostly amorphous nature but there are peaks confirming the existence of tetragonal as well as rutile structures of RuO2. The characteristic peak at 1563 cm−1 in FTIR confirms the formation of PPy. SEM image of the prepared hybrid flexible electrodes (HFEs) exhibits spherical structures embedded in PPy matrix. EDX pattern of the HFE shows the peaks for C, N, O and Ru. The prepared HFEs were electrochemically analyzed by cyclic voltammetry, galvanostatic charge discharge and electrochemical impedance spectroscopy. The observed maximum SC was found to be 1010.4 F g−1 at 5 mV s−1 in 0.2 M Na2SO4. [ABSTRACT FROM AUTHOR]

Hybrid nanocomposites comprised of metal oxide nanoparticles and three-dimensional (3D) graphene possess the advantages of metal oxide and graphene, which have generated extensive attention. Here, we fabricate flexible micro-supercapacitors (MSCs) based on hybrid materials of single-walled carbon nanotubes (SWCNT)-bridged laser-induced graphene fibers (LIGF) decorated with manganese dioxide (MnO 2) nanoparticles. SWCNT is deposited on the LIGF surface and the space between LIGF, which can bridge LIGF to form more conductive paths and provide more active areas to grow with MnO 2 nanoparticles. Profiting from the synergistic effect between conductive SWCNT-bridged LIGF network and the MnO 2 nanoparticles with high theoretical capacitance, the obtained flexible MSCs based on LIGF-C4/MnO 2 hybrid electrodes deliver an outstanding areal capacitance of 156.94 mF cm−2, which is about 8 times higher than that of LIGF-MnO 2 based MSC (20 mF cm−2). Additionally, the LIGF-C4/MnO 2 MSCs also exhibit considerable areal energy density of 21.8 μWh cm−2, long-term cycling stability, remarkable modular integration capability, and exceptional mechanical flexibility (with 90.5% capacitance retention after 1200 bending cycles). Therefore, the design of hybrid electrode materials proposed in this work offers a facile and novel method to develop flexible energy storage devices with high performance, suggesting great prospects for applications in future various wearable electronics. [Display omitted] • A highly conductive network is successfully prepared by the SWCNT bridging the laser-induced graphene fibers (LIGF). • Abundant MnO 2 nanoparticles are anchored on the SWCNT-bridged LIGF substrate via facile chemical bath deposition. • The flexible MSCs based on the LIGF-C4/MnO 2 composite materials deliver a superb areal capacitance of 156.94 mF cm−2. [ABSTRACT FROM AUTHOR]

Fiber‐based supercapacitors (FSCs) that display small volume, robust weavability, high power density, and long‐term stability, have urgently become the indispensable power supplies in smart wearable industries. Graphene fiber is regarded as an ideal FSCs electrode due to its remarkable natures of anisotropic framework, adjustable layer spacing, porous structures, large specific‐surface‐area, processable electroactivity, and high electronical and mechanical properties. This review, mainly focuses on the graphene fiber‐based supercapacitors (GFSCs), with respect to fiber preparation, micro‐nanostructure modulation, supercapacitor construction, performance optimization, and wearable applications. Various fiber fabrication strategies, including wet‐spinning, dry‐spinning, film conversion, confined hydrothermal self‐assembly, and microfluidic‐spinning are presented for fiber's structure manipulation and large‐scale production. Advanced nanostructures and electroactivity with various building principles, such as oriented alignment, porous network, hierarchical, and heterogeneous skeleton, engineered active‐sites, and mechanical regulation are discussed for boosting charge transfer, and ionic kinetic diffusion and storage. Especially, the optimizing approaches for regular unit alignment, enhanced interlayer interactions, modulated structural nano‐architecture are presented to deliver high capacitance and energy density. Moreover, the flexibility and stretchability of graphene fiber, together with wearable applications of power supply are highlighted. Finally, a short summary, current challenges and future perspectives for designing high energy density GFSCs are proposed. [ABSTRACT FROM AUTHOR]

Designing robust and cost‐effective electrocatalysts based on Earth‐abundant elements is crucial for large‐scale hydrogen production through electrochemical water splitting. Here, nitrogen‐doped carbon engrafted Mo2N/CoN hybrid nanosheets that are seamlessly oriented on hierarchical nanoporous Cu scaffold (Mo‐/Co‐N‐C/Cu), as highly efficient electrocatalysts for alkaline hydrogen evolution reaction are reported. The constituent heterostructured Mo2N/CoN nanosheets work as bifunctional electroactive sites for both water dissociation and adsorption/desorption of hydrogen intermediates while the nitrogen‐doped carbon bridges electron transfers between electroactive sites and interconnective Cu current collectors by making use of Mo‐/Co‐N‐C bonds and intimate C/Cu contacts at interfaces. As a consequence of unique architecture having electroactive sites to be sufficiently accessible, self‐supported nanoporous Mo‐/Co‐N‐C/Cu hybrid electrodes exhibit outstanding electrocatalysis in 1 m KOH, with a negligible onset overpotential and a low Tafel slope of 47 mV dec−1. They only take overpotential of as low as 230 mV to reach current density of 1000 mA cm−2. When coupled with their electro‐oxidized derivatives that mediate efficiently the oxygen evolution reaction, the alkaline water electrolyzer can achieve ≈100 mA cm−2 at 1.622 V in 1 m KOH electrolyte, ≈0.343 V lower than the device constructed with commercially available Pt/C and Ir/C nanocatalysts immobilized on nanoporous Cu electrodes. [ABSTRACT FROM AUTHOR]

Developing high-performing and scalable electrode materials for supercapacitors and batteries has been of tremendous interest for the world's forthcoming clean and renewable energy transition. As a versatile material, Two-dimensional graphitic carbon nitride (g-CN) has been utilized in electrochemical energy storage (EES) applications due to its nitrogen-rich adsorption sites, cost-effective production, and tunable electronic structure. The electrochemical performance of pristine g-CN has been boosted by forming hybrid architectures with highly conductive carbon-based materials, such as graphene, reduced graphene oxide, carbon nanofibers, carbon nanotubes, and beyond (e.g., MXene). Using such heterogeneous compositions for EES applications has significantly increased in recent years. This study reviews the g-CN/carbon nanomaterial (CNM) hybrids, considering the dimensionality in nanomaterials, and underscores the influence of the material's dimensionality and the synthesis/fabrication routes. The effect of structural and physicochemical changes on the electrode's electrochemical performance after hybridization is presented comparatively. Besides, the comprehensive review outlines challenges and future improvements in g-CN/CNM hybrid materials for outstanding developments in energy storage systems. [Display omitted] • Graphitic carbon nitride (g-CN)/carbon nanomaterial (CNM) hybrids are reviewed for supercapacitor and battery applications. • The impact of the CNM-type on the hybrid electrode's performance is examined through a chemical and physical perspective. • An overview of how hybrid electrode synthesis affects ion/electron transport, surface area, and porosity is provided. • Design-oriented control of the physicochemical properties for enhanced electrochemical performance is exemplified. • g-CN/CNM nanoarchitectures are emphasized as electrode materials with the potential for easy scalability. [ABSTRACT FROM AUTHOR]

To meet the requirement of clean and efficient energy storage system for practical applications, supercapacitors (SCs), which are promising candidates for the next‐generation energy storage devices, have received tremendous attention. Herein, a hybrid electrode consisting of copper nanowires (Cu NWs) and carbon nanotubes (CNTs) is prepared by simple vacuum‐filtration method. Both Cu NWs and CNTs have excellent conductivities, high aspect ratios, and large surface areas, in which the two kinds of materials are evenly dispersed and are entangled with each other. The electrochemical performance characterization of the Cu@CuO NWs/CNTs hybrid electrode shows high specific capacitance of 1.7 F cm−2 and excellent cycling characteristics of 97.4% after 5000 cycles. The hybrid electrode of Cu@CuO NWs/CNTs with one‐dimensional (1D) structure provides significant advantages in terms of electron/ion transport pathways. The SC devices with excellent electrochemical performance and stability clearly demonstrate their broad applications as low‐cost, high‐performance power supplies for electronic devices. [ABSTRACT FROM AUTHOR]

The application of non-linear signal analysis techniques to biomedical data is key to improve our knowledge about complex physiological and pathological processes. In particular, the use of non-linear techniques to study electroencephalographic (EEG) recordings can provide an advanced characterization of brain dynamics. In epilepsy these dynamics are altered at different spatial scales of neuronal organization. We therefore apply non-linear signal analysis to EEG recordings from epilepsy patients derived with intracranial hybrid electrodes, which are composed of classical macro contacts and micro wires. Thereby, these electrodes record EEG at two different spatial scales. Our aim is to test the degree to which the analysis of the EEG recorded at these different scales allows us to characterize the neuronal dynamics affected by epilepsy. For this purpose, we retrospectively analyzed long-term recordings performed during five nights in three patients during which no seizures took place. As a benchmark we used the accuracy with which this analysis allows determining the hemisphere that contains the seizure onset zone, which is the brain area where clinical seizures originate. We applied the surrogate-corrected non-linear predictability score (ψ), a non-linear signal analysis technique which was shown previously to be useful for the lateralization of the seizure onset zone from classical intracranial EEG macro contact recordings. Higher values of ψ were found predominantly for signals recorded from the hemisphere containing the seizure onset zone as compared to signals recorded from the opposite hemisphere. These differences were found not only for the EEG signals recorded with macro contacts, but also for those recorded with micro wires. In conclusion, the information obtained from the analysis of classical macro EEG contacts can be complemented by the one of micro wire EEG recordings. This combined approach may therefore help to further improve the degree to which quantitative EEG analysis can contribute to the diagnostics in epilepsy patients.

We report a gel polymer electrolyte (GPE) supercapacitor concept with improved pathways for ion transport, thanks to a facile creation of a coherent continuous distribution of the electrolyte throughout the electrode. Poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) was chosen as the polymer framework for organic electrolytes. A permeating distribution of the GPE into the electrodes, acting both as integrated electrolyte and binder, as well as thin separator, promotes ion diffusion and increases the active electrode–electrolyte interface, which leads to improvements both in capacitance and rate capability. An activation process induced during the first charge–discharge cycles was detected, after which, the charge transfer resistance and Warburg impedance decrease. We found that a GPE thickness of 12 μm led to optimal capacitance and rate capability. A novel hybrid nanocomposite material, formed by the tetraethylammonium salt of the 1 nm-sized phosphomolybdate cluster and activated carbon (AC/TEAPMo12), was shown to improve its capacitive performance with this gel electrolyte arrangement. Due to the homogeneous dispersion of PMo12 clusters, its energy storage process is non-diffusion-controlled. In the symmetric capacitors, the hybrid nanocomposite material can perform redox reactions in both the positive and the negative electrodes in an ambipolar mode. The volumetric capacitance of a symmetric supercapacitor made with the hybrid electrodes increased by 40% compared to a cell with parent AC electrodes. Due to the synergy between permeating GPE and the hybrid electrodes, the GPE hybrid symmetric capacitor delivers three times more energy density at higher power densities and equivalent cycle stability compared with conventional AC symmetric capacitors.

Increasing performance demand associated with the short lifetime of consumer electronics has triggered fast growth in electronic waste, leading to serious ecological challenges worldwide. Herein, a robust strategy for judiciously constructing flexible perovskite solar cells (PSCs) that can be conveniently biodegraded is reported. The key to this strategy is to capitalize on meniscus‐assisted solution printing (MASP) as a facile means of yielding cross‐aligned silver nanowires in one‐step, which are subsequently impregnated in a biodegradable elastomeric polyester. Intriguingly, the as‐crafted hybrid biodegradable electrode greatly constrains the solvent evaporation of the perovskite precursor solution, thereby generating fewer nuclei and in turn resulting in the deposition of a large‐grained dense perovskite film that exhibits excellent optoelectronic properties with a power conversion efficiency of 17.51% in PSCs. More importantly, the hybrid biodegradable electrode‐based devices also manifest impressive robustness against mechanical deformation and can be thoroughly biodegraded after use. These results signify the great potential of MASP for controllably assembling aligned conductive nanomaterials for biodegradable electrodes. As such, it represents an important endeavor toward environmentally friendly, multifunctional and flexible electronic, optoelectronic, photonic, and sensory materials and devices. [ABSTRACT FROM AUTHOR]

The application of non-linear signal analysis techniques to biomedical data is key to improve our knowledge about complex physiological and pathological processes. In particular, the use of non-linear techniques to study electroencephalographic (EEG) recordings can provide an advanced characterization of brain dynamics. In epilepsy these dynamics are altered at different spatial scales of neuronal organization. We therefore apply non-linear signal analysis to EEG recordings from epilepsy patients derived with intracranial hybrid electrodes, which are composed of classical macro contacts and micro wires. Thereby, these electrodes record EEG at two different spatial scales. Our aim is to test the degree to which the analysis of the EEG recorded at these different scales allows us to characterize the neuronal dynamics affected by epilepsy. For this purpose, we retrospectively analyzed long-term recordings performed during five nights in three patients during which no seizures took place. As a benchmark we used the accuracy with which this analysis allows determining the hemisphere that contains the seizure onset zone, which is the brain area where clinical seizures originate. We applied the surrogate-corrected non-linear predictability score (ψ), a non-linear signal analysis technique which was shown previously to be useful for the lateralization of the seizure onset zone from classical intracranial EEG macro contact recordings. Higher values of ψ were found predominantly for signals recorded from the hemisphere containing the seizure onset zone as compared to signals recorded from the opposite hemisphere. These differences were found not only for the EEG signals recorded with macro contacts, but also for those recorded with micro wires. In conclusion, the information obtained from the analysis of classical macro EEG contacts can be complemented by the one of micro wire EEG recordings. This combined approach may therefore help to further improve the degree to which quantitative EEG analysis can contribute to the diagnostics in epilepsy patients. [ABSTRACT FROM AUTHOR]

Soft electronics that seamlessly interface with skin are of great interest in health monitoring and human–machine interfaces. However, achieving mechanical softness, skin adhesiveness, and high conductivity concurrently has always been a major challenge due to the difficulty in bonding dissimilar materials while retaining their respective properties. Herein, the mechanically interlocked hydrogel–elastomer hybrid is reported as a viable solution to this problem. Hydrogels with low moduli and high adhesiveness are employed as the substrate, while porous elastomer webs are used as matrices to load conductive films and lock the hydrogels through a mechanically interlocked structure. The bonding strength between the hydrogel and elastomer in the interlocking hybrid structure is 14.3 times of that obtained via the physical stacking method. As a proof of concept, interlocking hybrids are used as on‐skin electrodes for electrophysiological signal recording including electromyography and electrocardiography. The robust hybrid electrodes are able to detect signals after multiple cycles. The proposed strategy not only is an effective approach to achieve interlocking structures, but also provides a new perspective for soft and stretchable electronics. [ABSTRACT FROM AUTHOR]

Alkali‐activated functionalized carbon nanotubes (AFCNTs) and 2D nanostructured MoS2 are investigated as a novel hybrid material for energy‐storage applications. The nanoflower‐like 2D MoS2 is grown on the surface of AFCNT using the controlled one‐step hydrothermal technique. The activation of functionalized carbon nanotubes results in greater performance due to the improved surface area. The Brunauer–Emmett–Teller (BET) surface area of the AFCNTs is found to be 594.7 m2 g−1 which is almost 30 times of the as‐prepared carbon nanotubes (CNTs). The improved surface area with attached hydroxyl and carboxylic functional groups helps in the attachment of MoS2 nanoflowers onto the AFCNT, thus reducing the interfacial resistance and providing an easy path for electron transfer. The electrochemical analysis shows a high specific capacitance of 516 F g−1 at 0.5 A g−1 with a corresponding energy density of 71.76 Wh kg−1, which is an encouraging reported value from AFCNT and MoS2 hybrid material. To the best of our knowledge, herein, the first report on AFCNTs and 2D MoS2 nanostructured hybrid electrode material for supercapacitor applications is provided, and promising results in terms of specific capacitance, energy density, and power density by boosting the properties of individual material are explained. [ABSTRACT FROM AUTHOR]

This paper reports on the preparation of polyaniline-carbon nanotube (PANi-CNT) hybrid electrodes via a facile electro-co-deposition method. In the process, carboxylated CNTs, which serve as counter anions in the electrodes, are incorporated into PANi. Supercapacitive properties of PANi-CNT hybrid electrodes are observed to depend on the degree of carboxylation of CNTs. Electrochemical measurements show two key results. First, the incorporation of CNTs observably improves the supercapacitive properties of PANi electrodes. Second, the CNTs with higher degree of carboxylation result in further improvement in supercapacitive properties of the hybrid electrodes. The former observation is attributed to the high electrical conductivity and large surface area of CNTs, which improve the electrical conductivities of the hybrids and facilitate the dispersion of PANi. The latter is in line with the fact that more CNTs are incorporated into the hybrids due to higher degree of carboxylation. The PANi-CNT electrodes prepared by CNTs with higher degree of carboxylation demonstrate remarkable supercapacitive performances, including high specific capacitance of 578.2 F g−1 and good rate performance. They also have superior cycling stability, showing 88.2% of capacitance retention after 10,000 cycles. [ABSTRACT FROM AUTHOR]

[Display omitted] • A radical polymer PETM was used to construct flexible hybrid electrodes. • PETM demonstrates multiple functions in the electrodes. • Thick electrodes were studied to achieve high energy density. • DFT calculations were conducted to verify the superiority of PETM. The combination of high output and high energy storage performance at the same time is a long-standing and formidable challenge in electrode technology. Herein, a multifunctional radical polymer binder, poly (ethylene-alt-TEMPO maleate) (PETM) is first introduced to construct flexible self-standing organic/inorganic hybrid electrodes, PETM/lithium iron phosphate (LFP)/single-walled carbon nanotubes (SWNT). Notably, PETM plays multifunctional roles in the PETM/LFP/SWNT electrodes as a polymer binder, electrochemical mediator, and auxiliary active material. First, PETM provides strong adhesive strength to generate robust structural integrity, allowing a three-dimensional hierarchical consecutive structure. Second, together with the electrochemical mediation of PETM, the hybrid structure greatly expedites electron/ion transportation, thus bringing fast redox reaction kinetics and high output. Third, PETM offer additional energy storage owing to the electro-activeness of radical groups. Coupled with the self-supporting property of the electrode without any redundant electro-inactive components, the electrode energy density can be substantially improved. Profiting from those advantages, the formed electrode achieves exceptional rate performance (97.5 mA h/g at 20 C), extraordinary specific/areal capacity (173 mA h g−1/8.2 mA h cm−2 at 0.1 C), and ultralong-life cycle under ultrahigh rate (over 2000 cycles at 20 C). More importantly, the electrode can be utilized as a flexible cathode in flexible batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] • Self-stabilised dispersion polymerised PANI/graphene nanoflake hybrid electrodes show a synergetic electrochemical performance. • The hybrid electrodes with 2:1 PANI/graphene nanoflake ratio show the highest specific capacitance of 454.9F g−1. • A symmetric supercapacitor using this electrode delivers an energy density of 25.4 Wh kg−1 even at a high-power density of 10 kW kg−1. • The supercapacitor retains 89.2% of its initial capacitance even after 10,000 continuous charge–discharge cycles at a current density of 5 A g−1. In this study, we prepared hybrid electrodes of self-stabilized dispersion polymerized (SSDP) polyaniline (PANI) and graphene nanoflakes by a facile solution intercalation approach. Unlike the conventional electrode preparation methods, the SSDP PANI dispersion was prepared by adopting the secondary doping method. The preparation of hybrid electrodes by a unique combination of these methods eliminates the use of binders and imparts excellent electrochemical properties to these electrodes due to synergistic effects. The optimized electrode (PG 2:1) demonstrates a specific capacitance of 454.9 F g−1 at a current density of 0.5 A g–1 and the symmetric supercapacitor using this electrode, achieved an energy density of 33.2 Wh kg−1 at a power density of 1 kW kg−1. Furthermore, even at a high-power density of 10 kW kg−1, the device delivers an energy density of 25.4 Wh kg−1. Interestingly, the symmetric supercapacitor retains 89.2 % of its initial capacitance even after 10,000 continuous charge–discharge cycles at a current density of 5 A g–1. The performance of these devices was also tested for different bending angles and was found to exhibit excellent stability. The superior performance of this hybrid electrode offers significant potential for the development of efficient binder-free flexible supercapacitors for portable and wearable devices. [ABSTRACT FROM AUTHOR]

Electrochemical capacitors have faced the limitations of low energy density for decades, owing to the low capacity of electric double-layer capacitance (EDLC)-type positive electrodes. In this work, we reveal the functions of interlayer confined water in iron vanadate (FeV 3 O 8.7 · n H 2 O) for sodium-ion storage in nonaqueous electrolyte. Using an electrochemical quartz crystal microbalance, in situ Raman, and ex situ X-ray diffraction and X-ray photoelectron spectroscopy, we demonstrate that both nonfaradaic (surficial EDLC) and faradaic (pseudocapacitance-dominated Na + intercalation) processes are involved in the charge storages. The interlayer confined water is able to accelerate the fast Na + intercalations and is highly stable (without the removal of water or co-intercalation of [Na-diglyme] + ) in the nonaqueous environment. Furthermore, coupling the pseudocapacitive FeV 3 O 8.7 · n H 2 O with EDLC-type activated carbon (FeVO-AC) as the positive electrode brings comprehensive enhancements, displaying the enlarged compaction density of ∼2 times, specific capacity of ∼1.5 times, and volumetric capacity of ∼3 times compared to the AC electrode. Furthermore, the as-assembled hybrid sodium-ion capacitor, consisting of an FeVO-AC positive electrode and a mesocarbon microbeads negative electrode, shows a high energy density of 108 Wh kg -1 at 108 W kg -1 and 15.3 Wh kg -1 at 8.3 kW kg -1 . Our results offer an emerging route for improving both specific and volumetric energy densities of electrochemical capacitors.

Hybrid electrodes for lithium‐ion batteries (LIBs) based on the dimensional combination of various nanomaterials have been widely investigated in recent years. This is an inevitable development trend that seeks to inherit and promote the remarkable achievements of the double designs for an ideal electrode in both performance and stability. However, a clear and in‐depth understanding of the origin of the common progress trends, as well as the opportunities and challenges of such designs, are somewhat elusive due to the lack of detailed reviews of the field. Herein, we present a review of the hybrid electrodes arising from triple and quadruple combinational dimensions in LIB applications. The critical challenges of normal electrode operation are discussed in a detailed way to better understand how interactions and synergistic effects in hybrid design affect the mechanical aspects, electrochemical properties, performance and cycle life of batteries. Finally, the developments and innovations in future electrodes based on these higher‐dimensional hybrid designs are presented. [ABSTRACT FROM AUTHOR]

We have evaluated the electrocatalytic activity of hybrid electrodes containing Fe(II) phthalocyanine and tested these electrodes for l -cysteine oxidation and l -cystine reduction. The hybrid electrodes consisted of pristine multi-walled carbon nanotubes and functionalized with COOH, NH 2 groups (MWCNT-p, MWCNT-c and MWCNT-a). These MWCNTs were modified with iron (II) phthalocyanine (FePc). The characterization of the hybrid systems was performed using X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and AFM with the purpose of elucidating the type of interaction between FePc and MWCNTs. The Fe(II)/(I) and Fe(III)/(II) redox potentials associated with the metal center where evaluated using cycling voltammetry. The redox processes are slightly affected by the presence of MWCNTs. The activity for both reactions increases substantially by the presence of modified MWCNTs essentially by an area effect. However, when the currents are normalized by the amount of active sites estimated from the surface coverages of FePc, the activities are still higher for FePc attached to MWCNTs. The data for l -cysteine oxidation fits well on a volcano correlation published previously for several metal phthalocyanines and metalporphyrins. Image 1 [ABSTRACT FROM AUTHOR]

In recent years, the electrochemical sensors are used extensively due to their unique properties, especially in the biomedical research. Conducting polymers are well known for their inbuilt charge transfer properties and biocompatibility. Modification of conducting polymers using metal particles, metal oxides, and carbon materials enhance the sensitivity, stability, and reproducibility of the electrode which enhances the overall sensor performance. In this present review, we discuss recent achievements of electrochemical biosensors and sensor performance of various nanostructured conducting polymers and various metal oxides. Various synthesis methodologies of nanostructured conducting polymers and metal oxide-based hybrid sensors are also discussed. Analytical performance of nanohybrids of metal oxides incorporated with conducting polymers such as polyaniline, polypyrrole, polythiophene and their derivatives is elaborated. The characteristics of conducting polymer-based hybrids, metal oxide-based hybrids, and their application in biosensors are reviewed. • The review covers a variety of metal oxide and conducting polymer based sensors. • Latest fabrication techniques to overcome previous sensor limitations have been covered. • Recently reported sensors have been thoroughly discussed. • Recent improvements in sensor parameters have been thoroughly covered. [ABSTRACT FROM AUTHOR]

• Nanostructured TiO 2 hybrids showed excellent performance in detecting various biological markers. • Various parameters have an influence for the electrochemical and sensing properties. • Nanostructured hybrids improved the selectivity and stability of various biosensors. Biosensors are promising biotechnology products that can be widely used for environmental monitoring, food analysis, and healthcare diagnostics. To detect analytes of interest, the use of nanotechnology in bio-analytical devices is advantageous for increased sensitivity, device simplification, and rapid sensing with multiple capabilities. Depending on the application, biosensors can be fabricated from different materials. TiO 2 is a semiconductor material and has received significant attention for various applications such as sensors, solar cells, water splitting, etc. The wide applicability of recently developed novel composition and structure of TiO 2 materials has accelerated the development and miniaturization of biosensor devices. This study focuses on recent achievements in TiO 2 nanostructured hybrids-based biosensors for detecting various biological markers important for healthcare. [ABSTRACT FROM AUTHOR]

Abstract Making composites of low-dimension oxides and carbons is one of the most effective strategies towards better energy storage materials. Among various carbons, biomass derived carbons with many distinguishing features show great advantages. We report herein a highly ordered mollusc-shell derived 3D carbon networks (MSDCN) for high-performance composite electrode materials. When Ni(OH) 2 is chosen as a conjoined component, the obtained Ni(OH) 2 /MSDCN composite exhibits a high specific capacity of 81 mAh g−1 at a high current density of 30 A g−1, and shows no obvious capacity fading during long life cycling at 6 A g−1. Symmetric solid-state energy storage devices based on Ni(OH) 2 /MSDCN are also assembled, which demonstrates a high energy density of 10.7 W h kg−1 at a power density of 0.51 KW kg−1 with good cycling stability over 10000 cycles. Red light-emitting diode (LED, 2 V) can be easily lightened by the prepared solid-state devices. Meanwhile, the successful synthesis of Co 3 O 4 nanocube/MSDCN and MnO 2 nanowire/MSDCN composites further reveal the high application potential of the MSDCN for high performance energy storage devices. Highlights • 3D carbon network (MSDCN) are prepared from mollusc shells. • Solid-state device based on the prepared hybrid Ni(OH) 2 /MSDCN exhibits good electrochemical property. • The proposed MSDCN can be a common substrate for high-performance metal oxides/carbon hybrid electrodes. [ABSTRACT FROM AUTHOR]

Mechanical motion sensing and monitoring is an important component in the field of industrial automation. Rotary motion is one of the most basic forms of mechanical motion, so it is of great significance for the development of the entire industry to realize rotary motion state monitoring. In this paper, a triboelectric rotary motion sensor (TRMS) with variable amplitude differential hybrid electrodes is proposed, and an integrated monitoring system (IMS) is designed to realize real-time monitoring of industrial-grade rotary motion state. First, the operating principle and monitoring characteristics are studied. The experiment results indicate that the TRMS can achieve rotation speed measurement in the range of 10–1000 rpm with good linearity, and the error rate of rotation speed is less than 0.8%. Besides, the TRMS has an angle monitoring range of 360° and its resolution is 1.5° in bidirectional rotation. Finally, the applications of the designed TRMS and IMS prove the feasibility of self-powered rotary motion monitoring. This work further promotes the development of triboelectric sensors (TESs) in industrial application.

Regarding the demand for new technologies for energy storage devices, supercapacitors can bridge the gap between conventional capacitors and batteries in terms of energy and power densities. It is reported that metal oxides (MOs), such as oxides of iron (Fe 2 O 3), nickel (NiO), and manganese (MnO 2 , Mn 2 O 3), among others, can act as a nucleus to obtain composites, interconnecting the polymer chains, with dimensions ranging from micrometer to nanometers, in addition to producing a porous morphology, which would be able to reach high specific surface areas. In this study, polyaniline (PANI) and its respective composites with iron oxides (Fe 2 O 3) (PANI/Fe 2 O 3), oxides nickel (NiO) (PANI/NiO) and manganese (MnO 2 , Mn 2 O 3) (PANI/Mn x O y) are developed, characterized, and compared. The field emission gun-scanning electron microscopy (FEG-SEM) images display that composites present porous morphology and dimensions ranging from micrometer, which can reach high specific surface areas. The Raman data exhibits that characteristic bands of polyaniline present in the composite materials underwent significant changes, which can be attributed to interactions of imine groups with metallic oxides. These interactions can be of the electrostatic, metal-organic, or hydrogen bonding type and directly influence the charge transfer and conductivity process, thus contributing to the increase in electrochemical performance. By electrochemical analyses, the nanocomposite materials synergism is proved, especially for PANI/Mn x O y. By electrochemical impedance spectroscopy (EIS), capacitive profiles of synthesized materials are clear with a phase angle close to 90° in lower frequencies regions associated with smaller impedance modulus values in the whole analyzed frequency range. PANI/Mn x O y composite also shows the highest capacitance value evaluated from a galvanostatic charge and discharge (GCD) of 115.78 F g−1. This is reinforced by its higher specific capacitance, energy, and power values of 205.55 F g−1, 21.9 W kg−1, and 1850 Wh kg−1, respectively, per CV. [Display omitted] [ABSTRACT FROM AUTHOR]

Hybridizing powdery carbons with transition metal phosphides (TMPs) can effectively address the issues of sluggish kinetics and volume expansion associated with TMPs in supercapacitors (SCs). However, the practical use of powdery TMPs/carbon materials in SCs is limited by tedious electrode preparation process, unfavorable performance, and inferior cycling stability. Herein, we develop carbon membrane-based hybrid electrodes (Co 2 P@CTF) by the direct carbonization of Co-containing tofu (TF) aerogel prepared by coagulating soybean proteins using Co2+ ions. During carbonization, the cross-linked protein frameworks were transformed into a porous, mechanically strong, and conductive carbon matrix, whereas the Co species were in situ self-phosphorized to be highly dispersed carbon-coated Co 2 P nanoparticles without using external phosphorus sources. The best Co 2 P@CTF electrode (Co 2 P@CTF-1000) demonstrates a high areal capacitance (C a) of 2.44 F cm−2 at 1.0 mA cm−2. Moreover, a symmetric SC assembled with Co 2 P@CTF-1000 deliveries a C a of 1.33 F cm−2 at 1.0 mA cm−2, achieves an energy density of 90 μWh cm−2 at a power density of 699.4 μW cm−2, and retains a 104.8% capacitance with a nearly unit coulomb efficiency at 10 mA cm−2 after 50000 cycles. This study offers an effective strategy towards carbon membrane-supported TMPs hybrid electrodes based on the direct self-phosphorization mechanism for the practical applications in SCs. • Porous carbon membrane-supported Co 2 P hybrid electrodes (Co 2 P@CTF) are developed. • The Co ions can be in situ self-phosphorized to form highly dispersed Co 2 P nanoparticles. • The Co 2 P@CTF electrodes feature good mechanical strength and electrolyte wettability. • The Co 2 P@CTF electrodes exhibit high areal capacitance and rate capability. • A Co 2 P@CTF-based SC exhibits high energy density and good cycling stability. [ABSTRACT FROM AUTHOR]

Abstract: A rod‐like hollow cobalt tungstate/non‐stoichiometric cobalt sulfide (CoWO4/Co1−xS) hybrid is successfully grown in situ on nickel foam through a simple two‐step hydrothermal process. Owing to the unique hollow structure, the as‐synthesized CoWO4/Co1−xS hybrid electrode possesses a large surface area and delivers a high specific capacitance of 1894.5 F ⋅ g−1 at a current density of 1 A ⋅ g−1. By using the CoWO4/Co1−xS hybrid electrode as the anode and an activated carbon (AC) electrode as the cathode, an asymmetric supercapacitor of CoWO4/Co1−xS//AC exhibits a high capacitance of 103.1 F ⋅ g−1 and high specific capacitance retention of 87.27 % after 5000 cycles. Furthermore, the asymmetric supercapacitor demonstrates a maximum power density of 4000 W ⋅ kg−1 at an energy density of 22.5 Wh ⋅ kg−1. The superior performance of the device can be ascribed to distinctive structure and positive synergistic effects in the hybrid. The facile preparation process and excellent performance presented here indicate the CoWO4/Co1−xS hybrid to be a promising candidate electrode material for supercapacitor applications. [ABSTRACT FROM AUTHOR]

Abstract: Ionic soft actuators, which exhibit large mechanical deformations under low electrical stimuli, are attracting attention in recent years with the advent of soft and wearable electronics. However, a key challenge for making high‐performance ionic soft actuators with large bending deformation and fast actuation speed is to develop a stretchable and flexible electrode having high electrical conductivity and electrochemical capacitance. Here, a functionally antagonistic hybrid electrode with hollow tubular graphene meshes and nitrogen‐doped crumpled graphene is newly reported for superior ionic soft actuators. Three‐dimensional network of hollow tubular graphene mesh provides high electrical conductivity and mechanically resilient functionality on whole electrode domain. On the contrary, nitrogen‐doped wrinkled graphene supplies ultrahigh capacitance and stretchability, which are indispensably required for improving electrochemical activity in ionic soft actuators. Present results show that the functionally antagonistic hybrid electrode greatly enhances the actuation performances of ionic soft actuators, resulting in much larger bending deformation up to 620%, ten times faster rise time and much lower phase delay in a broad range of input frequencies. This outstanding enhancement mostly attributes to exceptional properties and synergistic effects between hollow tubular graphene mesh and nitrogen‐doped crumpled graphene, which have functionally antagonistic roles in charge transfer and charge injection, respectively. [ABSTRACT FROM AUTHOR]

As typical energy storage devices, the extensive application of the supercapacitors is largely restricted by their relatively low energy storage efficiency, which motivates the development of various advanced electrode materials with sophisticated architectural design. Herein, we put forward a robust and controllable approach to construct a series of hybrid nanoarchitectures consisting of nanoflower-shaped MnO 2 nanocrystals grown on super-thin Ti 3 C 2 T x MXene nanosheets (MNF/Ti 3 C 2 T x) via a convenient co-precipitation process. Such a delicate configuration enables the nanoarchitectures to provide prominent structural merits, such as 2D thin-sheet structure with large surface area, porous MnO 2 nanoflower frameworks, activated electronic structure, and high electron conductivity. As a consequence, the optimized MNF/Ti 3 C 2 T x electrode manifests superior electrochemical capacitive properties with a maximum specific capacitance of 348.5 F g−1 at 0.5 A g−1, excellent rate property, and reliable cycling stability with 91.9% retention of initial capacitance after 5000 cycles, all of which are more competitive than those of conventional MnO 2 and Ti 3 C 2 T x electrodes. [Display omitted] • The stereoassembly of ε-MnO 2 nanoflowers on 2D Ti 3 C 2 T x MXene nanosheets is achieved. • MXene nanosheets are able to optimize the electronic and geometric structures of MnO 2. • The nanoflower-shaped MnO 2 affords numerous accessible electrochemically active sites. • The derived nanoarchitectures are expected to serve as promising electrode materials for supercapacitors. [ABSTRACT FROM AUTHOR]

• Arsenic abatement and removal of fluoride and silica from groundwater. • Al-Fe hybris electrodes are stacked in continuous electrocoagulation (EC) reactor. • World Health Organization recommendations for arsenic and fluoride were fulfilled. • Al and Fe react with silica producing flocs of aluminosilicates and iron silicates. • Arsenic adsorbs on aggregates, and fluoride substitutes a OH from aluminum flocs. This communication is about the removal of arsenic (As), fluoride (F −) and hydrated silica (HS) from real underground water (initial concentration: 28 µg L−1 arsenic, 1.55 mg L−1 F − , 155 mg L−1 HS, 35 mg L−1 sulfate, pH 7.4, and 470 µS cm−1 conductivity) by electrocoagulation (EC). The novel EC reactor consists of eight horizontally stacked cells using Fe and Al plates as sacrificial anodes with an upward flow. The abatement of As and the elimination at the same time of F − and HS was performed by analyzing the influence of the mean linear flow velocity (1.2 < u < 4.8 cm s−1) at different current densities (3 < j < 7 mA cm−2) imposed on the EC system. The best condition was carried out at j = 7 mA cm−2 and u = 1.2 cm s−1, achieving complete arsenic elimination, and a remaining F − concentration of 0.45 mg L−1, fulfilling the World Health Organization (WHO) guideline for arsenic (< 10 μg L−1) and fluoride (< 1.5 mg L−1). The remaining HS reached a value of 10 mg L−1. Spectroscopic techniques applied to the Fe-Al flocs evidenced the generation of iron oxides and hydroxides, as well as the formation of aluminosilicates. [Display omitted] [ABSTRACT FROM AUTHOR]

Biodiesel is a growing alternative to petroleum fuels and is produced by the catalyzed transesterification of fats in presence of an alcohol base. Transesterification processes using homogeneous catalysts are considered to be among the most efficient methods but rely on the feedstock quality and low water content in order to avoid undesirable saponification reactions. In this work, the electro-catalytic conversion of canola oil to biodiesel in a 1% aqueous methanolic and ethanolic reaction mixture was performed without the addition of external catalyst or cosolvent. An inexpensive stainless steel (SS) electrode and a hybrid SS electrode coated with an ion-exchange resin catalyst were used as cathode materials while the anode was composed of a plain carbon paper. The cell voltages were varied from 10 to 40 V and the reaction temperature maintained at 20 or 40°C. The canola oil conversion rates were found to be superior at 40°C without saponification reactions for cell voltages below 30 V. The conversion rates were as high as 87% for the hybrid electrode and 81% for the plain SS electrode. This work could inspire new process development for the conversion of high water content feedstock for the production of second-generation biodiesel.

In this work, the reduction and oxidation capacities of organic supporting electrolytes for ferricenium (Fc + ) and ferrocene (Fc) were investigated by micro and nano hybrid electrodes in this work. The Fc + can be produced in situ at the carbon electrode and collected simultaneously at the liquid/liquid (L/L) interface. The experiments were based on the generation/collection (G/C) technique and the redox capability of the supporting electrolytes was defined by the collection efficiency. Five common employed supporting electrolytes in the organic phase (TBADCC, TBATPB, TBATPBCl, TBATPBF and TBATPBF 5 ) were discussed and the experimental results indicated that the reduction power of these supporting electrolytes was weakened successively. The oxidation ability of cations of some supporting electrolytes (TPAsTPBF 5 , TBATPBF 5 and BTPPATPBF 5 ) were also tested using the same methodology, showing that TBA + and BTPPA + have little influence on this system in comparison with oxidation of Fc to Fc + by TPAs + . Besides, the different concentration of supporting electrolyte verse Fc was also studied to further prove the redox effect of supporting electrolytes on Fc + . [ABSTRACT FROM AUTHOR]

We explore different electrode microstructures and the associated implications on the electrochemical stability of activated carbon/lithium titanate (Li 4 Ti 5 O 12 , LTO) composite electrodes by incrementally increasing the LTO content. At low LTO concentrations, the electrochemical stability is progressively improved with respect to neat activated carbon based electrodes. This trend is abruptly changed for high LTO concentrations (72 mass%) as the electrolyte starts to decompose unexpectedly far below the electrochemical stability boundaries of the single materials. We attribute this to a loss of electrical percolation and local degradation spots caused by peculiarities of the carbon distribution: Initially the sub-micrometer-sized LTO solely occupies spaces between the large, micrometer-sized activated carbon. With increasing LTO content the activated carbon particles get separated in an insulating LTO matrix. Electrochemical stability can be reestablished with electronic conduction paths of well distributed sub-micrometer-sized carbon black particles. By this way, cell degradation can be reduced and the cycle life of cells with high LTO concentration is prolonged from 10 to >36,000 cycles. Finally, we propose a simple method to distinguish cell fading caused by electrolyte decomposition from cell fading caused by poor electrical percolation. [ABSTRACT FROM AUTHOR]

Transition-metal oxides show genuine potential in replacing state-of-the-art carbonaceous anode materials in lithium- or sodium-ion batteries because of their much higher theoretical capacity. However, they usually undergo massive volume change, which leads to numerous problems in both material and electrode levels, such as material pulverization, instable solid-electrolyte interphase, and electrode failure. Here, it is demonstrated that lithium-ion breathable hybrid electrodes with 3D architecture tackle all these problems, using a typical conversion-type transition-metal oxide, Fe3O4, of which nanoparticles are anchored onto 3D current collectors of Ni nanotube arrays (NTAs) and encapsulated by δ-MnO2 layers (Ni/Fe3O4@MnO2). The δ-MnO2 layers reversibly switch lithium insertion/extraction of internal Fe3O4 nanoparticles and protect them against pulverizing and detaching from NTA current collectors, securing exceptional integrity retention and efficient ion/electron transport. The Ni/Fe3O4@MnO2 electrodes exhibit superior cyclability and high-capacity lithium storage (retaining ≈1450 mAh g−1, ≈96% of initial value at 1 C rate after 1000 cycles). [ABSTRACT FROM AUTHOR]

Abstracts A novel heterogenous Co 3 O 4 -nanocube/Co(OH) 2 -nanosheet hybrid is prepared by a controllable facile one-pot hydrothermal reaction. The resulting Co 3 O 4 nanocubes are highly uniform in morphology, and are distributed uniformly on the individual Co(OH) 2 nanosheets. Such unique nanostructural features show significant advantages for applications as flexible supercapacitor electrodes in terms of enhanced durability and capacitance. The as-prepared electrode has offered a large capacitance of 1164 F g −1 at 1.2 A g −1 . When being paired with activated carbon, the resulting flexible all-solid-state device exhibited a maximum energy density of 9.4 mWh cm −3 . It is worthwhile noting that this as-assembled device showed little capacitance decay after over 5000 cycles with 97.4% retention of its original specific capacitance. Such a high performance outperforms most metal oxides-based electrodes and shows the advantages of the hybrid strategy, which shed light on exploring robust and cheap electrode materials for high-performance flexible supercapacitors. [ABSTRACT FROM AUTHOR]

Polymer solar cells (PSCs) possess the unique features of semitransparency and coloration, which make them potential candidates for applications in aesthetic windows. Here, the authors fabricate inverted semitransparent PSCs with high-quality hybrid Au/Ag transparent top electrodes and fine-tuned dielectric mirrors (DMs). It is demonstrated that the device color can be tailored and the light harvesting in the PSCs can be enhanced by matching the bandgap of the polymer donors in the active layer with the specifically designed maximum-reflection-center-wavelengths of the DMs. A detailed chromaticity analysis of the semitransparent PSCs from both bottom and top (mirror) views is also carried out. Furthermore, the inverted semitransparent PSCs based on PTB7-Th:PC71BM with six pairs of DMs demonstrate a maximum power conversion efficiency (PCE) of 7.0% with an average visible transmittance (AVT) of 12.2%. This efficiency is one of the highest reported for semitransparent PSCs, corresponding to 81.4% of the PCE from opaque counterpart devices. The device design and processing method are also successfully adapted to a flexible substrate, resulting in a device with a competitive PCE of 6.4% with an AVT of 11.5%. To the best of our knowledge, this PCE value is the highest value reported for a flexible semitransparent PSC. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide (rGO) is added to WO 3 and WS 2 to develop several hybrid electrode materials, including rGO/WO 3 , rGO/WS 2 , and rGO/WO 3 /WS 2 by a simple and cost-effective hydrothermal method to enhance the electrochemical performance. The structural/ morphological analysis of synthesized rGO/WO 3 , rGO/WS 2 , and rGO/WO 3 /WS 2 hybrids were extensively characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), Raman spectra, thermogravimetric analysis (TGA) and Brunauer-Emmett-Teller (BET) surface area. The extensive characterization shows that WO 3 /WS 2 nanoparticles were homogeneously dispersed throughout the surface of rGO. The rGO/WO 3 /WS 2 exhibits higher specific capacitance of 750 F/g at 10 mV/s as compared to rGO/WS 2 (481 F/g), rGO/WO 3 (382 F/g), and rGO (154 F/g). The rGO/WO 3 /WS 2 electrode was found to have R ct and R f values of 1.3 Ω cm2 and 1.5 Ω cm2, respectively. These values were found to be much lower than that of rGO electrode (47.2 Ω cm2 and 36.4 Ω cm2), indicating that the rGO/WO 3 /WS 2 has much less resistances, which may be one of the primary causes of the outstanding electrochemical properties of the rGO/WO 3 /WS 2. The retention capacity of 95.33 % upto 10,000 cycles at 1 A/g shows that this rGO/WO 3 /WS 2 hybrid electrode also exhibits good cycling stability. The rGO/WO 3 /WS 2 composites' respective energy and power densities are observed to be 702 Wh/kg and 5912 W/kg. The rGO/WO 3 /WS 2 hybrid has been shown to be a superior anode material in supercapacitors because of the synergistic interaction of WS 2 , rGO, and WO 3. These advantages include a bigger contact surface area, a shorter ion diffusion path, great charge transfer, and, most importantly, rGO's improved specific capacitance. It reveals that the rGO/WO 3 /WS 2 hybrids can be a promising electroactive material for supercapacitor applications. [Display omitted] • The rGO/WO 3 /WS 2 electrode was fabricated and characterized. • The incorporation of WO 3 /WS 2 in the rGO has improved the electrochemical performance. • The rGO/WO 3 /WS 2 electrode- retained 95.33 % of its specific capacitance after 10,000 cycles. • The rGO/WO 3 /WS 2 electrode showed specific capacitance of 750 F/g at 1 A/g. • The stability of the electrode was enhanced without altering its morphology. [ABSTRACT FROM AUTHOR]

CoFe 2 O 4 /Graphene Nanoribbons (GNRs) nanocomposite was successfully fabricated and utilised as an electrode active material for high-energy supercapacitor cells. Thanks to the outstanding physicochemical features of a graphene nanoribbon with excellent electrical conductivity and the synergistic effect with cobalt ferrite, as well as the pseudocapacitive effect. The CoFe 2 O 4 /GNRs nanohybrid offered an exceptional specific capacitance of 922 F g−1 (415 C g−1) at 1.0 A g−1 in 3.0 M KOH electrolyte in a standard 3-electrode set-up. Additionally, the impressive supercapacitive performance metrics showed that the suggested electrode had a distinctive morphology and could be a candidate for capacitive energy storage systems. These metrics included good cycle stability and 87% capacitance retention at the end of the 10,000th CV cycle. Moreover, the asymmetric supercapacitor cell (ASC) was designed by assembling CoFe 2 O 4 /GNRs and activated carbon (AC). The resultant ASC provided an improved specific capacitance of 487.85 F g−1 (683 C g−1) at 1.0 A g−1. At this current density value, the energy density and the power density values were computed as to be 132.8 Wh.kg−1 and 632.39 W kg−1. The highest power density was discovered to be 6730.76 W kg−1 at 10.0 A g−1, whereas the energy density was determined as 8.75 Wh.kg−1 at this current density. The results of the work proved that CoFe 2 O 4 /GNRs nanohybrids are up-and-coming electrode active materials for advanced electrochemical energy storage and conversion technologies. CoFe 2 O 4 /Graphene nanoribbons as a promising positive electrode material for high-energy density asymmetric supercapacitor. [Display omitted] • A viable tip to achieve a high-energy supercapacitor is to tailor advanced material. • Hybrids of carbon materials and metal-oxides are promising electrode materials. • CoFe 2 O 4 /Graphene Nanoribbons were fabricated and utilised in a supercapacitor cell. • CoFe 2 O 4 /Graphene Nanoribbons offered outstanding electrochemical characteristics. • Supremacy of hybrid nanocomposite was proven in an asymmetrical cell. [ABSTRACT FROM AUTHOR]

[Display omitted] • The rGO/TiS 2 /MoO 3 electrode is fabricated. • The incorporation of TiS 2 /MoO 3 in the reduced graphene oxide has improved the electrochemical performance. • The rGO/TiS 2 /MoO 3 electrodes retained 98.56 % of their specific capacitance after 8000 cycles. • The rGO/TiS 2 /MoO 3 nanocomposite electrode showed specific capacitance of 1044 mAh/g, for current density of 1 A/g. • The stability of the nanocomposite was enhanced without altering its morphology and chemical structure. Reduced graphene oxide (rGO) is added to MoO 3 and TiS 2 to develop several hybrid electrode materials, including rGO/MoO 3 , rGO/TiS 2 , and rGO/MoO 3 /TiS 2 to enhance the electrochemical performance. SEM/EDX, TEM, XRD, XPS, and Raman techniques are used to study the resulting hybrid electrode materials. The specific capacitance and charge–discharge stability of the synthesized rGO/MoO 3 , rGO/TiS 2 , and rGO/MoO 3 /TiS 2 electrode materials are assessed using galvanostatic and cyclic voltammetry testing. The rGO/MoO 3 /TiS 2 exhibits higher specific capacitance of 1043.72 mA h/g at 20 mV/s as compared to rGO/TiS 2 (625.61 mA h/g), rGO/MoO 3 (567.54 mA h/g), and rGO (154.40 mA h/g), among the examined. All electrochemical measurements were conducted in a 3 M KOH solution. The rGO/MoO 3 /TiS 2 electrode was found to have R ct value of 20.8 Ω.cm2. This value was much lower than that of the rGO electrode (89.8 Ω.cm2), indicating that the rGO/MoO 3 /TiS 2 exhibits much lower resistance, which causes the improved electrochemical performance of the rGO/MoO 3 /TiS 2. The retention of capacitance of 98.56 % after 8,000 cycles at 1 A/g shows that this rGO/MoO 3 /TiS 2 hybrid electrode also exhibits good cycling stability. The rGO/MoO 3 /TiS 2 composites' respective energy and power densities are determined to be 882 Wh/kg and 5773 W/kg. The good electrochemical performance of the rGO/TiS 2 /MoO 3 composite anode is closely related to its structure, in which the TiS 2 /MoO 3 nanoparticles are not only homogeneously anchored on the surface but also embedded in the interlayer of the rGO sheets; hence the volume change and aggregation of the TiS 2 /MoO 3 nanoparticles can be effectively hindered. On the other hand, rGO itself is an electronic conductor; the rGO and TiS 2 /MoO 3 nanoparticles connect closely, which offers large electrode/electrolyte contacting area, short path length for transporting of ions. [ABSTRACT FROM AUTHOR]