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• rGO/PANI@PANI film is prepared by chemical and electrochemical polymerization. • rGO/PANI film acts as the working electrode for gradient PANI electrodeposition. • The rGO/PANI@PANI electrode shows high specific capacitance and rate capability. • The symmetric device attains high energy density and excellent cyclic stability. In this study, we present the construction of the hierarchical graphene/polyaniline (PANI) supercapacitor electrode composites through a two-step PANI deposition approach of in-situ chemical and electrochemical polymerization. The graphene oxide (GO)/PANI colloid synthesized by chemical method undergoes the water evaporation and GO reduction to form the hydrated reduced GO (rGO)/PANI films on carbon cloth (CC) substrates. The resulting integrated rGO/PANI/CC films could be directly used as the electrodes to electrodeposit supplemental PANI on the subsurface/surface to obtain the rGO/PANI@PANI/CC electrodes with PANI distribution gradient. Benefited from the hierarchical PANI loading on the porous graphene scaffold with efficient PANI utilization in the electrochemical process, the as-prepared electrode can deliver a superior capacitance of 1131.6 F g−1 at 2 A g−1 with a high retention of 87.7% at 40 A g–1. Meanwhile the all-solid-state symmetric device achieves a large energy density of 52.6 Wh kg−1 and prominent cyclic stability. The excellent electrochemical performances of the electrodes manifest the feasibility of this reported strategy designing new carbon-based composites towards high energy-storing system with promising application prospect. [Display omitted] [ABSTRACT FROM AUTHOR]

A redox reversible composite anode with Fe-Ni alloy nanoparticles in situ growth on SrLaFeO 4 -type and LaFeO 3 -type oxide substrates has been prepared for intermediate temperature solid oxide fuel cell (IT-SOFC) by reducing perovskite precursor La 0.4 Sr 0.6 Fe 0.75 Ni 0.1 Nb 0.15 O 3-δ (LSFNNb) in wet H 2 at 900 °C for 1 h. The anode has shown an excellent electrochemical catalytic activity for oxidation of hydrogen with much smaller E a (25.1 ∼ 68.9 kJ mol −1 ) than the value (>160 kJ mol −1 ) at Ni-YSZ anode. A scandium stabilized zirconia (ScSZ) electrolyte supported SOFC with the anode achieves maximum power densities of 0.71, 0.52, 0.35, and 0.21 W cm −2 at 800, 750, 700 and 650 °C, respectively in wet H 2 (3% H 2 O), and the corresponding R p of 0.16, 0.21, 0.35, and 0.60 Ω cm 2 under OCV. Moreover, the single cell shows stable power output during ∼105 h operation at 800 °C under 0.7 V in wet H 2 after a initial degradation, indicating that R-LSFNNb is an excellent candidate as anode of IT-SOFC. [ABSTRACT FROM AUTHOR]

• Graphene/PANI/MnO 2 composites are fabricated by facile two-step electrodeposition. • Graphene hydrogel films act as working electrodes for sequential electrodeposition. • The ternary composite electrode exhibits excellent capacitive performance. • The symmetric device performs well in rate capacity, stability and energy density. The incorporation of various capacitive materials to fabricate multi-component electrodes has emerged as a feasible methodology toward high-performance supercapacitors. In this paper, a facile two-step electrodeposition method is proposed to construct polyaniline (PANI)/MnO 2 hybrid nanostructure on reduced graphene oxide (RGO) matrix for the ternary supercapacitor electrodes. By the sequential potentiostatic methods, PANI is first electropolymerized on RGO hydrogel films before MnO 2 granules are electrodeposited on the RGO/PANI conductive substrates to obtain the free-standing composite films. The resulting RGO/PANI/MnO 2 ternary composite electrodes present significantly promoted capacitive properties compared with the binary RGO/PANI electrodes. Particularly, the optimized electrode and corresponding all-solid-state device could achieve the high specific capacitances of 942.6 and 205.0 F g–1 at 1 A g–1 with superb capacitance retention of 86.4% and 80.3% at 30 A g–1, respectively. The device delivers a maximum energy density of 41.0 Wh kg–1 and demonstrates outstanding capacitance holdings of 96.1% after 10,000 cycles at 30 A g−1, 87.8% after 5000 cycles at 10 A g−1, and 82.5% after 3000 cycles at 5 A g−1, respectively. The prominent electrochemical performances of the ternary composite can be ascribed to the fact that graphene supplies the conductive matrix to immobilize the active pseudocapacitive constituents, while PANI and MnO 2 can compensate each other to surmount the disadvantages of inferior conductivity or stability. [Display omitted] [ABSTRACT FROM AUTHOR]

Three graphite materials with different structures, including graphite nanofiber (GNF), graphite nanosheet (GNS), and graphite nanoball (GNB), were used as the catalytic films on the counter electrodes (CEs) of dye–sensitized solar cells (DSSCs). Compared to GNF and GNS, GNB not only provides a higher degree of defects in the sp 2 plane structure but also possesses aboundant hydroxyl functional groups as the electro-catalytic active sites for I 3 − reduction; thereby, the intrinsic heterogeneous rate constant ( k 0 ) and effective electro-catalytic surface area ( A e ) of GNB-based CE are both higher than the values of GNF-based and GNS-based CEs. The GNB-based DSSC with showed the power conversion efficiency ( η ) of 7.88%, while those GNF-based and GNS-based DSSCs showed η ’s of 3.60% and 2.99%, respectively. Moreover, it is also observed that the η of the GNB-based DSSC (7.88%) is quite close to that of a Pt-based DSSC ( η =8.38%); this implies that the GNB can become a potential candidate to replace the expensive Pt, owing to its low-cost. [ABSTRACT FROM AUTHOR]

As the catalytic material for the counter electrode (CE) of a dye-sensitized solar cell (DSSC), a composite film of nickel nanoparticles (Ni-NPs) and poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) was deposited on an FTO glass substrate, by using a home-made polymeric dispersant, poly(oxyethylene)-segmented imide (POEM). Scanning electron microscopy (SEM), atomic force microscopy (AFM), and energy dispersive X-ray spectroscopy (EDX) were used to characterize the films. A solar-to-electricity conversion efficiency (η) of 7.81% was achieved for the DSSC using Ni-NPs/PEDOT: PSS, while the DSSC with the Pt CE showed a ηof 7.63%. The best composite film showed a high stability, when it was subjected to potential cycling for 100 cycles in an electrolyte containing the redox couple, iodide/triiodide (I - /I 3 − ), while the Pt film showed a considerable decrease in its stability. In replacing the conventional sputtered Pt film as the CE in a DSSC, the Ni-NPs/PEDOT: PSS film exhibited multiple advantages of higher power conversion efficiency, higher stability of the catalytic film, and less expensive material cost. The photovoltaic parameters of the cells were substantiated by incident photon-to-current conversion efficiency (IPCE) spectra, electrochemical impedance spectroscopy (EIS), Tafel polarization plots, and cyclic voltammetry (CV). [ABSTRACT FROM AUTHOR]

Highlights: [•] Double-shelled Mn2O3 hollow microspheres are prepared by a multi-step. [•] synthesis procedure. [•] Solid, hollow and yolk-structured Mn2O3 spheres are prepared for comparison. [•] The double-shelled hollow Mn2O3 is superior in electrochemical properties. [ABSTRACT FROM AUTHOR]

Abstract: Three-dimensional (3D) porous amorphous SnO2 thin films were deposited on Ni foam substrates by Electrostatic Spray Deposition (ESD) technique as anodes for Li-ion batteries. These films display good capacity retention of 94.8% after 100 cycles at 0.5C and rate capability of 362mAh/g at 10C. The improved performance originates from the fact that the 3D porous structure offers a “buffer zone” to accommodate the large volume change during cycling, and the foam-like substrate maximizes the contact area between electrode and electrolyte. The facile ESD method can be potentially extended to prepare other 3D porous functional materials. [Copyright &y& Elsevier]

Abstract A novel ruthenium complex capped with three triphenylamine units was synthesized and was high-rate anodically electropolymerized to form dense thin films of 33-nm thickness/per potential cycle on indium-tin oxide (ITO) electrodes. The films were studied by UV–vis absorption and X-ray photoelectron spectroscopy, atomic force microscopy, scanning electron microscopy, X-ray diffraction, cyclic voltammetry and photoelectrochemical measurements. Electrical conductivity of an electropolymerized film has also been measured by two-probe method. The results revealed that even the monolayer metallopolymeric thin films presented surface-controlled RuIII/II and TPA+1/0 associated redox behaviours and exceptionally strong photocurrent generation properties. As irradiated with white light at 100 mW/cm2, a monolayer film-modified ITO electrode without an applied bias voltage in 0.1 M Na 2 SO 4 aqueous solution showed a significant cathodic photocurrent of 10.7 μA cm−2, which compares favorably with those previously reported for indium-tin oxide electrodes modified by Ru(II) complex-based electrostatically self-assembled and solvent-casting films under similar experimental conditions. The mechanism of the cathodic photocurrent generation mechanism is discussed. [ABSTRACT FROM AUTHOR]

SO 2 is one of the critical poisoning species to Pt based catalysts of proton exchange membrane fuel cells (PEMFCs). Catalysts suffer severe performance degradation even trace amount of SO 2 presenting in the hydrogen or air. To enhance the SO 2 electrooxidation of Pt catalyst, we prepared Pt/CeO 2 /C composite catalysts via a one-pot synthesis method. The CeO 2 nanoparticles initially deposited on carbon black, and followed by Pt nanoparticles selectively nucleating on CeO 2 surface. The rich Pt-CeO 2 interface facilitates the oxygen migration, enhancing SO 2 electrooxidation and ORR activity. The catalysts containing 10 and 20 wt.% CeO 2 show the best performance, i.e., peak potentials of SO 2 electrooxidation are 0.06 and 0.09 V lower than Pt/C, respectively, ORR mass activity is over twofold greater, and area-specific activity is one fourth higher than Pt/C. Oxygen provided by CeO 2 reduced the SO 2 coverage on Pt surface and changed the dominant adsorbing state of SO 2 , hence, is vital to the SO 2 electrooxidation. Besides, accelerated durability test confirmed that CeO 2 could also improve the durability of Pt based catalysts. [ABSTRACT FROM AUTHOR]

Polypyrrole (PPy) with various morphologies were synthesized by chemical oxidative polymerization and further used as the counter electrode (CE) in dye–sensitized solar cells (DSSCs). The conventional anionic surfactant, docusate sodium salt (AOT), cationic surfactant, cetylmethyl ammonium bromide (CTAB), and the newly developed polymeric dispersant, poly(oxyethylene)–imide (POEM), were employed in the PPy synthesis. Scanning electron microscopy images (SEM) revealed diversified morphologies of the synthesized PPy nanoparticles with irregular sheet (IS), hierarchical nanosphere (HNS), and nanosphere (NS), corresponded to the choice of the commercial surfactants AOT and CTAB, as well as the home–made POEM, respectively. Fourier transform spectroscopy (FT–IR) and X–ray diffraction (XRD) analysis were used to confirm the PPy structures and crystalline properties. When fabricated into films and used as CE in DSSCs, the PPy–HNS demonstrated the superior cell efficiency of 6.71 ± 0.16% to those of PPy–IS (5.46 ± 0.31) and PPy–NS (6.31 ± 0.24), respectively. The excellent electrocatalytic ability of PPy–HNS was essentially attributed to its high electrochemical surface area ( A e ), which was quantitatively calculated through a rotating disk electrode system by using the Koutecky–Levich equation. Brunauer–Emmett–Teller (BET) surface area measurement, electrochemical impedance spectroscopy (EIS), and cyclic voltammetry (CV) were also used to substantiate the explanation for the DSSC performances. [ABSTRACT FROM AUTHOR]

• A novel active layer configuration with enhanced interfacial effect is proposed. • Reduced graphene oxide film is cut into two for each polyaniline electrodeposition. • The twin composite films are parallelly assembled for supercapacitor electrode. • The electrode displays excellent specific capacitance and cycling stability. • The all-solid-state device exhibits high energy density toward application potential. For the traditional supercapacitors based on the graphene@polyaniline (PANI) film prepared by electropolymerization, the interfacial contact between the graphene substrate and PANI shell plays a vital role in improving the PANI stability and the electrochemical capacitance of the active layer. In this work, we propose a novel strategy that the reduced graphene oxide (RGO) hydrogel film with given size could be divided into two for respective PANI electrodeposition and the two graphene@PANI films are assembled parallelly on carbon cloth to obtain the supercapacitor electrode. Owing to the additional lateral RGO/PANI interface, the resulting electrode delivers a high specific capacitance of 949 F g−1 at 1 A g−1 and 760 F g−1 even at the high current density of 20 A g−1. The corresponding binder-free symmetric supercapacitor device could attain a maximum energy density of 18.2 Wh kg−1 and a maximum power density of 4.75 kW kg−1, with a high capacitance retention of 93.1% after 10000 charge/discharge cycles. These superior properties of the electrodes based on the parallel RGO/PANI films testify the rational design of the active layer configuration for enhanced interfacial effect. This work would provide a novel pathway towards the preparation of high-performance supercapacitor electrodes. [Display omitted] [ABSTRACT FROM AUTHOR]

Chalcogenodiazolo [3,4- c ]pyridine, an important analogue of benzothiadiazole (BT), have stronger electron-accepting nature and unique electrochemistry and electrochromic advantages over BT in the NIR region, inspiring us to explore chalcogenodiazolo [3,4- c ]pyridine-based donor-acceptor-type (D-A) conjugated polymers. Herein, a series of chalcogenodiazolo [3,4- c ]pyridine and alkyl substituted 3,4-propylenedioxythiophenes (ProDOTs) bearing D-A-type conjugated precursors were synthesized by Stille coupling, and electropolymerized to yield the corresponding polymers. The electrochemistry behavior and electrochromic properties of the polymers were comparatively investigated by cyclic voltammetry (CV) and spectroelectrochemistry in detail. All the precursors revealed strong orange/purple/pink/bluish violet light emission with fluorescence quantum yields ranging from 0.09 to 0.60. Electrochromic results demonstrated that chalcogenodiazolo [3,4- c ]pyridine-ProDOTs polymers revealed relatively good transmittance changes ( ΔT %) of 38%, high coloration efficiency of 370 cm 2  C −1 in the near-infrared (NIR) region and excellent switching stability (less than 4% after 2000 cycles). In comparison with polymers from chalcogenodiazolo [3,4- c ]pyridine and thiophene, 3-alkylthiophene and EDOT, these polymers displayed higher coloration efficiency and better stability, resulting from the introduction of ProDOTs donor units. From these results, chalcogenodiazolo [3,4- c ]pyridine-ProDOTs can be further explored as green and NIR electrochromic materials towards indoor electrochromic products and flexible displays. [ABSTRACT FROM AUTHOR]

Heteroatom-doped carbon nanomaterials with well-defined porous are used as anode materials for SIBs due to their exceptional structural characteristics. In this work, porous N-doped carbon networks composed with ultrathin carbon nanosheets were synthesized via the direct pyrolysis of Vitamin B5. The content of nitrogen, specific surface area, porous structure of the N-doped carbon nanosheet networks were adjusted by changing reaction temperatures. The formation mechasim of the ultrathin N-doped carbon nanosheet networks was also proposed. The generation of calcium carbonate/calcium oxide used as a self-template renders the formation of the porous structure via thermal treatment. The optimized samples possess a superior lithium and sodium storage: 1534 mAh g −1 at 100 mA g −1 vs. Li/Li + and 335 mAh g −1 at 100 mA g −1 vs. Na/Na + , with nearly 100% cycling Coulombic efficiency, remarkable cycling retention and high rate capacity. Additionally, good electrocatalytic activity for ORR via a 4e −1 pathway determines that the resulting primary Zn-air battery showed high discharge power energy density (80 mW cm −2 ), high reversibility and stability over continuous cycles. [ABSTRACT FROM AUTHOR]

A facile, time-saving and one-step process to prepare graphene-based materials with excellent comprehensive capacitive performance is very promising for practical applications. Here, porous nitrogen-doped graphene/carbon nanotubes composite (PNGC) with loosened structure was prepared by pyrolysis method and the porous structure of PNGC was controlled by combined action of urea and low-cost lignosulfonate. PNGC is equipped with porous structure and thin graphene nanosheets, and meanwhile possess numerous active sites and high surface areas. Importantly, PNGC exhibits a high specific capacitance of 246.6 F g −1 at a current density of 0.5 A g −1 and high stability of 96.5% capacitance retention ratio after 2000 cycles at 100 mV s −1 , indicating an excellent performance of PNGC. Furthermore, the corresponding mechanism of pore formation in PNGC is hence proposed. This work of obtaining PNGC is of paramount importance for the future practical application of electrode materials for supercapacitor application. [ABSTRACT FROM AUTHOR]

• TMSO additive effectively removes trace H 2 O and corrosive HF from the electrolyte. • TMSO increases the inorganic content in SEI/CEI layers to enhance ionic conductivity and stability. • TMSO builds a stable CEI layer to improve the SMBs stability in FEC-containing electrolytes. • SMBs exhibited remarkable electrochemical performance in the reformulated electrolyte. Rechargeable sodium batteries have become an important complement to lithium secondary batteries and other energy devices due to their lithium-like operating mechanism and abundant sodium resources. Sodium metal batteries (SMBs) with high energy density can be applied in more aspects, but still faces more prominent challenges such as sodium dendrite growth and severe electrode-electrolyte interface reactions. Fluoroethylene carbonate (FEC) additive can effectively improve the stability of sodium metal anode due to the formation of a stable solid electrolyte interfacial (SEI) layer on sodium surface. However, the protective effect is not sufficient in suppressing sodium dendrite and corrosion of electrolyte as its easily ring-opening polymerization induced by Lewis acid (especially PF 5) in carbonate electrolytes. Here, 3-Trimethylsilyl-2-oxazolidinone (TMSO) as a multifunctional additive that not only removes H 2 O and HF from the electrolyte, but also inhibits the decomposition of NaPF 6 and improves the stability of FEC-containing electrolytes. Besides, TMSO can form a stable cathode electrolyte interfacial (CEI) layer on Na 3 V 2 (PO 4) 3 (NVP) cathode surface, alleviating NVP cracking and structural pulverization and thus endowing the long-term cycling stability of NVP cathode with low interfacial resistance. Notably, with the optimized electrolyte, the Na||NVP metal battery exhibits stable cycle performance with a capacity retention of 93.1% after 1400 cycles at room temperature and higher capacity retention of 96.6% for 270 cycles at 55 °C. [Display omitted] [ABSTRACT FROM AUTHOR]

Nickel hexacyanoferrate (NiHCF) flower-like nanosheets coated three dimensional (3D) hierarchical porous Ni composite films are successfully prepared by the combination of hydrogen-bubble template electro-deposition and electrochemical polymerization methods. The novel 3D porous NiHCF/Ni composite films demonstrate excellent electrochemical performance as binder-free integrated electrodes for supercapacitors in KNO 3 neutral electrolyte. Comparing to the NiHCF coated on smooth Ni film, the 3D hierarchical porous NiHCF/Ni film electrodes exhibit about 10 times larger specific capacitance in KNO 3 neutral electrolyte. The 3D porous NiHCF/Ni film electrodes also illustrate good long-term stability for about 18,000 charge-discharge cycles. The improvement of electrochemical performance might be ascribed to the large specific area, highly conductive pathway and fast ion diffusion for the flower-like NiHCF nanosheets directly growth on the 3D hierarchical porous interconnected conductive scaffold current collectors. [ABSTRACT FROM AUTHOR]

The gram-scale synthesis of graphene based mesoporous SnO 2 composite (G-M-SnO 2 ) has been successfully realized based on kirkendall effect. When used as anode for lithium ion batteries, it delivers a high reversible capacity of 1354 mAhg −1 after 50 cycles at 100 mAg −1 and excellent rate capability of 664 mAhg −1 at 2 Ag −1 . The outstanding lithium storage performance mainly results from the synergistic effect of the ultrasmall SnO 2 and conductive graphene nanoparticles, which not only enhanced the conductivity of the whole electrode but also provide buffer matrix for the expansion of SnO 2 nanoparticles during charge-discharge process. Furthermore, the ultra-small size of SnO 2 shortens the diffusion length of Li + /e − in SnO 2 . [ABSTRACT FROM AUTHOR]

Highlights: [•] A one-step sol-gel route with resorcinol-formaldehyde resin is designed to synthesis LiNi0.5Mn1.5O4. [•] Fd-3m phase delivers an excellent high rate performance and stable cycling retention. [•] A double “w”-shape R-V curve is a potential tool to indicate structure transition. [Copyright &y& Elsevier]

Highlights: [•] A unique bowl-like hollow spherical Co3O4 structure is prepared through a simple, low-cost and mass-yield method. [•] Such a bowl-like hollow Co3O4 microsphere demonstrates extraordinary rate and cycling performance for Li-storage. [•] The sodium-storage behavior of Co3O4 is investigated for the first time. [ABSTRACT FROM AUTHOR]

Highlights: [•] A polyoxometalate-based composite film decorated by CdS nanoparticles was fabricated by LbL technique. [•] Incorporation of CdS nanoparticles greatly improved electron transfer ability and electrochromic performance. [•] The composite film exhibited good stability, quick switching time and high optical contrast. [•] The mild electrolyte of pH 7 was used in the electrochromic process of the composite film, which is friendly to the environment. [Copyright &y& Elsevier]

Abstract: The α-Fe2O3 powders composed of different flower-like or yarn-like clusters are prepared by a thermal decomposition process of iron alkoxide precursors, which are obtained via a simple reaction between iron acetylacetonate and ethylene glycol in an oil bath. X-ray diffraction, thermogravimetric analysis, scanning electron microscopy, Brunauer–Emmett–Teller measurement, and galvanostatic cell cycling are employed to characterize the structures and electrochemical performance of these α-Fe2O3 samples. The results show that these α-Fe2O3 electrodes have stable cycling performance with a reversible capacity of over 800mAhg−1 after 40 cycles. The sample with optimized structure shows the best rate performance with a high capacity of 622mAhg−1 at the current density of 4687mAg−1. The experimental results suggest that such an α-Fe2O3 powder is a promising anode material for high energy-density lithium-ion batteries. [Copyright &y& Elsevier]

Abstract: A plate-like carbon-coated Li3V2(PO4)3 (LVP/C) powder composed of nanoplates was synthesized by a hydrothermal route. The structure and electrochemical properties of the LVP/C are characterized by X-ray diffraction, scanning and transmission electron microscopy, and galvanostatic charge–discharge cycling. This LVP/C electrode exhibits good rate performance at room temperature with a specific capacity of 113.8 and 128.8mAhg−1 at 6C rate in the voltage range of 3.0–4.3V and 3.0–4.8V, respectively. The sample also shows good cycling performance with 91.4% and 85% of capacity retention after 200 cycles at 1C rate. Even at −20°C, the plate-like LVP/C delivers a stable cycling performance with a specific capacity of 120.7mAhg−1, being 95.3% of the capacity at room temperature, and after 80 cycles, the capacity retention is 97.2%. [Copyright &y& Elsevier]

Abstract: Micrometer Li1.05Mn1.95O4 has been synthesized by solid state reactions with the nano-Mn3O4 as a precursor. X-ray diffraction, scanning electron microscopy and laser particle sizer are employed to investigate the structures, morphologies and particle size distributions of the powder. The micrometer Li1.05Mn1.95O4 exhibits good rate performance at room temperature with a specific capacity of 98.4mAhg−1 at 5C. The Li1.05Mn1.95O4/Li half cell also shows good cycling performance at elevated temperature with 90.5% of its initial capacity retained after 100 cycles at 1C. At −20°C, the Li1.05Mn1.95O4 delivers a stable cycling performance with a specific capacity of 84.5mAhg−1, being 84.1% of the capacity at room temperature. The cyclic voltammetry (CV) and rate performance measurements illustrate an increasing polarization with decreasing the temperature. In addition, the diffusion coefficients of lithium ions in Li1.05Mn1.95O4 at various temperatures (25, 0, −10 and −20°C) are determined to be in the magnitude of 10−10 to 10−12 cm2 s−1 by cyclic voltammetry (CV) method. [Copyright &y& Elsevier]

• A donor–acceptor copolymer from bisEDOT and isoindigo was firstly synthesized. • The polymer shows reversible and stable electrochromism with a low bandgap of 1.02 eV. • The polymer exhibits excellent EC performance with ΔT of 90% and CE up to 1025 cm2 C−1. • The fabricated ECDs reveal reversible and stable color change from green to sky-blue. High-performance electrochromic materials with high optical contrast, coloration efficiency, and excellent stability have always been critical for polymer electrochromics, and will boost diverse applications including flexible displays and wearable electronics. Herein, we develop a donor-acceptor-donor type copolymer from strong electron-withdrawing acceptor unit isoindigo and electron-donating moiety bis-EDOT by synthesizing and electropolymerizing its precursor (E)-1,1′-dihexyl-6,6′-bis(2,2′,3,3′-tetrahydro-[5,5′-bithieno[3,4-b][1,4]dioxin]-7-yl)-[3,3′-biindolinylidene]-2,2′‑dione (BisE−IDOH−BisE). Such polymer exhibits a low optical bandgap of 1.02 eV with stable and reversible electrochromism from kelly-green to sky blue. Further kinetic studies demonstrate that this polymer displays intriguing overall electrochromic performances throughout the NIR window with simultaneously high optical contrast up to 90%, high coloration efficiency of 1025 cm2 C−1, fast switching time of 1.1 s, and excellent reversible stability (< 4% loss upon 5000 cycling), which presents one of the best overall performances among the reported electrochromic polymers so far. With these amazing electrochromic properties, isoindigo-EDOT based polymers can be further developed towards device patterning and real applications like flexible indoor decoration displays and near infrared camouflage. [Display omitted] [ABSTRACT FROM AUTHOR]

Lithium-sulfur batteries are spotlighted as the promising next-generation batteries because of their high energy density and low-cost. Nevertheless, intrinsic low conductivity, notorious shuttle effect, and sluggish redox kinetics of sulfur cathode greatly impede their commercialization. Herein, we design and demonstrate a powerful combined strategy to build a novel hybrid architecture for hosting sulfur, which are achieved by growing Ni 2 P nanodot-enriched 3D graphene-like carbon onto carbon fiber paper (NP-3DGC@CFP) via a facile one-step carbonization approach. In the integrated NP-3DGC@CFP/S electrode: micro-mesoporous 3DGC provides abundant space and complicated pore structures to accommodate sulfur and physically confine polysulfide species; polar Ni 2 P nanodots chemically immobilize the lithium polysulfides and accelerate electrochemical reaction kinetics; flexible CFP serves as mechanical scaffold to support the electrode and avoids binder-related limitations. As a result, self-supported NP-3DGC@CFP/S cathode demonstrates an excellent combination of capacity, rate, cycling endurance (1409.4 mAh g−1 at 0.1 C, 538.2 mAh g−1 at 5 C, 786.3 mAh g−1 with 72.7% retention at 0.5 C for 300 cycles) and anti-self-discharge capability. Significantly, such cathode also shows satisfied cycling stability at a high sulfur loading of 6.5 mg cm−2 or at a high rate of 2 C, demonstrating its bright perspective for practical application. [ABSTRACT FROM AUTHOR]