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Ammonia borane (NH3BH3, AB) has attracted attention as a carbon-free energy source owing to its non-toxicity, high solubility in water, and high stability under ambient conditions. Unlike its traditional application as an efficient hydrogen storage material, AB has the potential to be used in alkaline fuel cells directly as an anode fuel. The direct ammonia borane fuel cell (DABFC) with a high equilibrium voltage of 1.616 V possesses high capacity and energy density with a value of 5200 A h kg−1 and 8400 W h kg−1, respectively. The AB oxidation reaction (ABOR) as the anodic reaction of the DABFC is the key to improving the electrochemical performance of the whole fuel cell. Up to now, there has been no report summarizing the direct application of AB as a fuel. In this mini-review, the mechanism, catalysts, applications, and challenges of AB applied as a fuel are discussed. [ABSTRACT FROM AUTHOR]

Modified graphene/muscovite (MGMu) nanocomposite was synthesized with muscovite (Mu) and silane coupling agent modified graphene oxide through a simple hydrothermal method that exhibited excellent dispersion stability in oil. Compared with the base oil sample, the average friction coefficient and wear scar diameter of the MGMu oil sample decreased by 64.4 and 20.0%, respectively, and the microhardness of its wear scar was increased by 16.1%. The MGMu showed better tribological performance than its individual component due to the synergetic effect between the two components. The lubrication mechanism was proposed according to the morphology, chemical composition, and microhardness of the surface of wear scars. MGMu as an oil additive could fill between the friction pairs, cling to some asperities, and occur relative sliding between unit layers, thus playing a role in lubrication. It was found that MGMu would react with the surface of the friction pair during the friction process to generate Fe2O3, SiO2, SiC, and new aluminosilicate, which formed a self-repairing layer with high hardness. This chemically reactive film exhibited a lower shear strength, which made the oil sample containing MGMu have a lower coefficient of friction. [ABSTRACT FROM AUTHOR]

The synthesis of multi‐carbon products through electrochemical CO2 reduction reactions has attracted great interest from researchers. Herein, nitrogen‐ and carbon‐doped copper nanocatalyst (NC−Cu) containing abundant Cu−N−C active sites was prepared by thermal decomposition of the complexes containing copper and melamine. The NC−Cu catalyst exhibited an ideal current density of 22 mA cm−2 at −0.93 V versus reversible hydrogen electrode (vs. RHE) in CO2‐saturated 0.5 M KHCO3 medium, with ethanol as the predominant product at −0.93 V (vs. RHE) and a maximum Faraday efficiency of 31 %. The current density of the catalyst remained almost unchanged after 20 h of electrolysis, indicating its excellent stability. The excellent catalytic ability is attributed to the abundant Cu−N−C active sites of NC−Cu with 3D porous microstructure. [ABSTRACT FROM AUTHOR]

Long-cycle stability and high-energy density are big challenges for developing high-performance hybrid supercapacitor (HSC) electrode materials. In this work, molybdenum-doped Co3O4 nanosheets arrays on nickel foam (noted as MoxCo1.5−xO/NF) are successfully prepared via facile one-step electrodeposition followed by annealing for hybrid supercapacitors. The experimental and calculated results indicate that the band gap modification and conductivity enhancement of MoxCo1.5−xO lead to excellent capacitive performance due to the doping of Mo into Co3O4. The as-prepared Mo0.25Co1.25/NF electrode demonstrates a high specific capacity of 128.2 mAh g−1 (923 F g−1) at 1 A g−1 (60% higher than the undoped Co3O4) and superior cycle stability with 95.2% capacity retention after 10,000 cycles at 10 A g−1. The assembled HSC delivers high-energy density of 64.3 Wh kg−1 at the power density of 794.1 W kg−1 and with 87.7% capacity retention after 10,000 cycles. This work can present a new strategy to fabricate the three-dimensional high-performance integrated electrode materials by a facile electrodeposition for heteroatom-doped transition metal oxide for high-performance supercapacitors. [ABSTRACT FROM AUTHOR]

Ammonia borane (NH3BH3, AB), a carbon-free-energy material, has attracted enormous attention not only as the hydrogen storage source but also as the anodic fuel for direct AB fuel cells (DABFCs). The rational design of electrocatalysts for AB oxidation reaction (ABOR) is the key to improve the electrochemical performance of DABFCs. Herein, copper-doped nickel metaphosphates (Cu–Ni(PO3)2) with modulated electronic structure and abundant lattice defects through tuning dopant ratios are synthesized and applied towards ABOR for the first time. The optimal Cu–Ni(PO3)2 catalyst shows excellent electrocatalytic performance with an onset potential of −0.282 V versus the reversible hydrogen electrode (vs. RHE) which is superior to the published noble-metal and other transition metal electrocatalysts. And the density functional theory (DFT) computations verified that the active sites in the Cu–Ni(PO3)2 towards ABOR are the dopant Cu ions, the optimized Ni ions, and the induced lattice distortions, which indicates that the doping of Cu ions can indeed improve the electrocatalytic activity of the host catalyst Ni(PO3)2. This work provides a new candidate for the electrocatalyst of ABOR. [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li–S) batteries are widely regarded as the most promising batteries for the future due to their higher specific capacity and lower prices. Various strategies are utilized to alleviate the shortcomings of Li–S batteries failing to reach theoretical capacity. However, basic research at the molecular level continues to be lacking. Therefore, we use molecular dynamics to study the details of the solvated structure of Li–S batteries electrolyte and the nature of the transport process, revealing the relationship between the solvated structure of the electrolyte of LiPF6 and the organic solvent ethylene carbonate/dimethyl carbonate (EC/DMC). The electrolyte of Li2S4 was first simulated in a pure solvent environment. Then the LiPF6 salt was added to the model to simulate a typical electrolyte for a working Li–S battery. Regarding the rationality of the solvent system, various reference systems such as density, dielectric constant, viscosity and diffusion coefficient of the solvent were used for verification. And the detailed composition of the first solvation shell of the polysulfate ion and the coordination number of the ions are discussed. These results provide new insights into the use of EC/DMC electrolytes in Li–S batteries, while at the same time providing a basis for efficient future predictions of electrolyte structure and transport in complex electrode confinements. The radius of the first solvation shell of each component is the PF 6 − anion at about 0.22–0.28 nm, the DMC solvent at about 0.32–0.36 nm and the EC solvent at about 0.41 nm, respectively. The first solvation shell according to these distributions has a radius of about 0.5 nm. The coordination number in the first solvation shell is plotted, which is about 1.88 for PF 6 − , 1.86 for DMC, and about 0.14 for EC. In conclusion, 3.88 molecules are produced in the first solvation shell of the ion. [ABSTRACT FROM AUTHOR]

Cobalt‐glycolate (Co‐glycolate) is a kind of layered coordination polymer with abundant electrochemically active sites but low conductivity. The fabrication of heterostructures is a novel strategy to enhance the electrical conductivity. Herein, Co‐glycolate serves as a host substrate for the in situ growth of guest ZIF‐67 to build MOFs‐on‐CPs heterostructures (named Co‐glycolate /ZIF‐67) via a simple ligand‐exchange method as an anode for lithium‐ion batteries. A heterojunction interface with distorted lattice between the Co‐glycolate phase and the ZIF‐67 phase can be observed. Theoretical calculations and experimental results simultaneously prove that the formed heterojunction reduces the band gap and enhances the conductivity. Compared with both single components, optimized Co‐glycolate/ZIF‐67 shows a higher capacity and better cycling and rate performances due to the improved charge‐transfer rate of the heterostructure. Its specific capacity remains at 652 mAh g−1 after 800 cycles at 1 A g−1. These excellent electrochemical properties can be due to the smaller size, rough surface, and strong combination of a unique heterostructure as well as to the greatly reduced band gap of the individual components. A lithium‐storage mechanism for Co‐glycolate/ZIF‐67 was proposed. This work provides a new strategy for building MOFs‐on‐CPs heterostructures to improve the electrochemical performance of metal‐glycolate‐based electrode materials for energy‐storage and conversion systems. [ABSTRACT FROM AUTHOR]

Engineering delicate structures/morphologies and coordinated components of electrocatalysts are of great importance to optimize physicochemical properties of materials and thus enhance their electrocatalytic performance. Herein, we demonstrate a facile sequential template-engaged strategy for fabricating Co–Ni–Fe phosphide hollow nanoboxes with hierarchical structures and desired hetero-metal compositions (Co–Ni–Fe–P HNBs). Starting from ZIF-67 templates, binary-metal Co–Ni and ternary-metal Co–Ni–Fe HNBs are sequentially synthesized and further phosphidated into hetero-metal Co–Ni–Fe–P HNBs. As-resultant Co–Ni–Fe–P HNBs endow multiple structural and compositional merits that expose abundant active sites, accelerate mass/ion diffusion and optimize adsorption energies of oxygen and hydroxyl groups, thus kinetically promoting electrocatalytic oxygen evolution reaction (OER). Specifically, Co–Ni–Fe–P HNBs disclose remarkable OER activity with an overpotential of 249 mV at 10 mA cm−2 and stability with 86% activity retained over 24 h, which represents one of the toppest values of OER electrocatalysts. This work thus paves an effective protocol to rationally engineer hierarchical and hetero-metal electrocatalysts towards targeted applications. [ABSTRACT FROM AUTHOR]

Wearable electronic devices are the new darling of consumer electronics, and energy storage devices are an important part of them. Here, a wearable lithium‐sulfur (Li‐S) bracelet battery using three‐dimensional (3D) printing technology (additive manufacturing) is designed and manufactured for the first time. The bracelet battery can be easily worn to power the wearable device. The "additive" manufacturing characteristic of 3D printing provides excellent controllability of the electrode thickness with much simplified process in a cost‐effective manner. Due to the conductive 3D skeleton providing interpenetrating transmission paths and channels for electrons and ions, the 3D Li‐S battery can provide 505.4 mAh g−1 specific capacity after 500 cycles with an active material loading as high as 10.2 mg cm−1. The practicality is illustrated by wearing the bracelet battery on the wrist and illuminating the red light‐emitting diode. Therefore, the bracelet battery manufactured by 3D printing technology can address the needs of the wearable power supply. [ABSTRACT FROM AUTHOR]

The rational construction of the chemical composition and morphological structure of electrocatalysts has been considered as the key to their electrochemical performance and energy storage. Herein, we report the facile fabrication of the hierarchical Ni2P–Co2P–Fe2P hybrid hollow nanoprism (abbreviated as NiCoFeP-HN), which could efficiently work as the oxygen evolution reaction (OER) electrocatalyst in the rechargeable Zn–air battery. NiCoFeP-HN was synthesized via an in situ ion exchange reaction of nickel–cobalt precursors with [Fe(CN)6]3− at room temperature and the subsequent phosphorization at 300 °C under N2. The ion exchange procedure was crucial for preserving the nanoprism morphology and enhancing the OER performance. NiCoFeP-HN exhibited satisfactory activity with a small overpotential of 294 mV at 10 mA cm−2 and remarkable stability for over 12 h. Compared to the conventional RuO2 + Pt/C Zn–air battery, the NiCoFeP-HN + Pt/C based Zn–air battery has exhibited superior energy density and much better cycling stability. This work presents a facile and efficient avenue for the construction of hollow nanostructures and hybrid compositions, and provides a promising candidate with good electrochemical performance and energy storage. [ABSTRACT FROM AUTHOR]

The current study reports a new, simple and fast method using a flake-like dysprosium molybdate (Dy2MoO6; FL-DyM) nanostructured material to detect the antibiotic drug metronidazole (METZ). This nanocomposite material was employed on the surface of a glassy carbon electrode (GCE) to develop the electrode (FL-DyM/GCE). Further, the synthesized FL-DyM was systematically characterized by powder X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray diffraction (EDS), elemental mapping, X-ray photoelectron spectroscopy (XPS), and Brunauer–Emmett–Teller (BET) analyses. Cyclic (CV) and differential pulse voltammetry (DPV) techniques were used to study the electrochemical properties. The FL-DyM/GCE-based sensor demonstrated excellent selectivity and sensitivity for the detection of the drug METZ, which could be attributed to the strong affinity of FL-DyM towards the –NO2 group in METZ, and the good electrocatalytic activity and conductivity of FL-DyM. The fabrication and optimization of the working electrode were accomplished with CV and DPV obtained by scan rate and pH studies. Compared to the bare GCE and other rare-earth metal molybdates, the FL-DyM/GCE sensor displayed a superior electrocatalytic activity response for METZ detection. The sensor demonstrated a good linear relationship over the concentration range of 0.01–2363 μM. The quantification and detection limits were found to be 0.010 μM and 0.0030 μM, respectively. The FL-DyM/GCE sensor displayed excellent selectivity, repeatability, reproducibility, and stability for the detection of METZ in human urine and commercial METZ tablet samples, which validates the new technique for efficient drug sensing in practical applications. [ABSTRACT FROM AUTHOR]

Supercapacitors are developing in terms of high power and energy densities. Carbon materials can meet this challenge to a certain extent. A sustainable high‐performance carbon material for supercapacitors was prepared through the simple and green thermal pyrolysis of orange peels as raw materials by using KOH as an activator. The biomass‐derived carbon materials activated at different temperatures were evaluated as electrode materials. The adsorption properties, structure, and surface elemental chemical states of the prepared materials were studied. Carbonation temperature plays a key role in the preparation of materials, and it has different effects on the physical and electrochemical properties of materials. The opc700 and opc800 samples have large pore volumes, which provide the necessary space for the storage of electrolyte ions. The temperature has a pronounced effect on the specific surface area and the electrochemical performance. The specific surface area of opc800 is as high as 2004 m2 g−1 and the pore volume is 1.24 cm3 g−1. The maximum specific capacity of opc800 is 306.6 F g−1 at 0.5 A g−1 and the specific capacitance is 251.2 F g−1 at 20 A g−1. [ABSTRACT FROM AUTHOR]

Nb2O5@carbon/reduced graphene oxide (M-Nb2O5@C/rGO) composites are fabricated by annealing the precursor of graphene oxide supported Nb-based metal organic frameworks for the first time. The lithium ion capacitor using M-Nb2O5@C/rGO as the anode and activated carbon as the cathode delivers a high energy density of 71.5 W h kg−1 and excellent cycling stability. [ABSTRACT FROM AUTHOR]

Binder-free electrodes with core–shell structures have shown great potential in a variety of important energy storage systems. In order to endow the core–shell hierarchical structure with enhanced electrochemical properties, rationally designed and fabricated hierarchical structures with controllable morphology and great electrical conductivity are highly desired. In this work, a uniform dendritic S-Co3O4@NiCo2S4 hierarchical structure grown on Ni foam was successfully designed and synthesized via sulfur-doping of Co3O4 (S-Co3O4) as the inner core with enhanced conductivity. The hierarchical electrode exhibited high areal capacity (10.9 mA h cm−2 at a current density of 8 mA cm−2), a good rate performance (72.5% retention after increasing the current densities from 8 to 30 mA cm−2), and excellent cycling stability (97.3% retention after 5000 cycles). Moreover, a hybrid energy storage battery-supercapacitor device, constructed from a S-Co3O4@NiCo2S4 positive electrode and an active carbon (AC) negative electrode, showed high energy density and power density. Contributing to short ion diffusion, large electroactive sites and low contact resistance, our work not only demonstrates a promising electrode for energy storage battery-supercapacitor hybrid (BSH) devices, but also provides an attractive strategy for the design of electrode materials. [ABSTRACT FROM AUTHOR]

Poly(3-methylthiophene)/reduced graphene oxide (P3MT/RGO) modified glassy carbon electrode (GCE) was fabricated via a facile procedure. P3MT was directly electrodeposited on the RGO coated electrode and employed for the electrochemical detection of paracetamol (PCT). The morphology of composite was characterized by scanning electron microscopy (SEM). Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were used to investigate the electrochemical behaviors of PCT on P3MT/RGO/GCE. Experimental parameters, such as the scan rates, polymerization laps and the pH of buffer solution were optimized. Under the optimal conditions, the anodic peak current in DPVs varies linearly with the concentration of PCT, and the limit of detection was 0.025 μ M. Moreover, the proposed P3MT/RGO/GCE also exhibited superior stability and reproducibility. The poly (3-methylthiophene)/reduced graphene oxide (P3MT/RGO) material was firstly proposed for the fast, sensitive electrochemical determination of paracetamol (PCT). The RGO can efficiently provide abundant reaction sites and promote the electron transfer, while the P3MT was electrodeposited on the surface of RGO/GCE. The redox current response increased further and the reversibility of the redox reaction was improved. The developed sensor showed excellent stability, high selectivity, low detection limit and good applicability in real samples. [ABSTRACT FROM AUTHOR]

Abstract: Pyrrole was utilized to induce the cross‐link of graphene oxide, resulting in a stable hydrogel. Following, polypyrrole/graphene composite was prepared using direct microwave treatment of this pyrrole‐induced hydrogel. Where, graphene oxide was chemically reduced and pyrrole in the composite was polymerized. The polypyrrole was homogeneously distributed throughout the graphene sheets. The as‐synthesized composite had a three‐dimensional, cross‐linked structure with advanced electro‐catalytic properties for hydroquinone and catechol. This feature was demonstrated by the superior electrochemical reversibility and good peak separation exhibited by the novel composite material. Accordingly, the detection of the two dihydroxybenzenes using this material produced a detection limit of 0.88 μM for hydroquinone and 0.69 μM for the catechol. [ABSTRACT FROM AUTHOR]

Abstract: A new efficient composite catalyst (CuIMnFeIIIO/NG) for oxygen reduction reaction (ORR) in both alkaline and neutral media, is successfully prepared via a facile, clean, low‐cost and reproducible solvothermal method without any further treatments. The nanoparticles consisting of crystalline phases of Fe2O3, MnCO3 and amorphous Cu2O&MnxOy (CuIMnO), are anchored on nitrogen‐doping graphene (N/C atomic ratio up to 10.56 %), which offer various active sites toward ORR. The synergistic catalytic effect between these components affords excellent ORR performance with comparable onset potential and current density to commercial Pt/C in both pH‐situations, and a 4‐electron‐transfer path during oxygen reduction. Furthermore, comparative experiment results are discussed to describe the different degrees of ORR contribution in different medium from metal species and nitrogen doping. Meanwhile, superior methanol tolerance and high stability of CuIMnFeIIIO/NG can make it a promising alternative for expensive commercial Pt‐based electrocatalysts in corresponding alkaline and neutral fuel cells. [ABSTRACT FROM AUTHOR]

It is of great practical importance to design low-cost materials as catalysts for the oxygen reduction reaction (ORR) and as an anode for sodium–ion batteries (SIBs). In this paper, we report a class of nitrogen-doped carbon materials with a three-dimensional nanofibrous network derived from inexpensive biomass bacterial cellulose (BC) for both ORR and SIB applications. The samples were prepared by treating the BC aerogels with various amounts of pyrrole to ensure a uniform coating on the surface of the BC nanofibers, followed by a carbonization process under different temperatures. The products were essentially carbon nanofibers coated by a nitrogen-doped carbon layer and retained the initial structure of BC. The optimum amount of pyrrole was 0.05 mL and the optimum carbonization temperature was 900 °C. Our best catalyst exhibited good electrocatalytic performance and durability in ORR, without the presence of noble metals. An electrode made from the same material has also demonstrated a stable cycling performance and superior rate capability in SIB application. Our work has demonstrated a rational design of electroactive carbon materials from a low-cost precursor. [ABSTRACT FROM AUTHOR]

Abstract: The large‐scale, low‐cost preparation of Pt‐based catalysts with high activity and durability for the methanol oxidation reaction is still challenging. The key to achieving this aim is finding suitable supporting materials. In this paper, N‐doped carbon nanofibrous networks are prepared by annealing a gel containing two inexpensive and ecofriendly precursors, that is, bacterial cellulose and urea, for the loading of Pt nanoparticles. An undoped analogue is also prepared for comparison. Meanwhile, the effect of the annealing temperature on the performance of the catalysts is evaluated. The results show that the N doping and higher annealing temperature can improve the electron conductivity of the catalyst and provide more active sites for the loading of ultrafine Pt nanoparticles with a narrow size distribution. The best catalyst exhibits a remarkably high electrocatalytic activity (627 mA mg−1), excellent poison tolerance, and high durability. This work demonstrates an ideal Pt supporting material for the methanol oxidation reaction. [ABSTRACT FROM AUTHOR]

Constructing heterogeneous components with a yolk−shell structure is highly desirable for improving the lithium-storage performance of metal oxides, owing to the unique synergies of nanostructures and composite materials. In this work, a novel heterogeneous hybrid of yolk−shell CuO@CuFe2O4 was synthesized through a simple two-step method. Starting with Cu2O, the yolk−shell precursor was prepared through an interfacial reaction. After subsequent heat treatment of the precursor in air, yolk−shell CuO@CuFe2O4 was obtained. A reasonable mechanism for the formation process of the yolk−shell CuO@CuFe2O4 has been presented. The relatively high electrical conductivity of CuFe2O4, unique yolk−shell structure, and firm shell of the CuO@CuFe2O4 account for the extremely enhanced electrochemical properties compared to bare CuO. In particular, discharge capacities of 505 and 36 mA h g−1 were delivered after 200 cycles at 500 mA g−1 by the yolk−shell CuO@CuFe2O4 and bare CuO, respectively. This work not only provides a promising alternative anode material for lithium-ion batteries, but also develops a new strategy to design the nanostructure and components of metal oxides for application in lithium-ion batteries. [ABSTRACT FROM AUTHOR]

We have successfully prepared poly (3,4-ethylenedioxythiophene) (PEDOT)/N-doped reduced graphene oxide (N-rGO) by electrodeposition, post-reduction, and doping N atoms with a microorganism (as a green reagent) to modify PEDOT and resolve the exfoliation and fragmentation problems of pristine PEDOT. This modification greatly improves the electrochemical properties of PEDOT, showing great potential for a bio-electrode coating material, which should have excellent electrochemical properties, stability and biocompatibility. The as-prepared PEDOT/N-rGO shows lower impedance, and higher capacitive performance and cyclical stability than pristine PEDOT due to the doping of N-rGO. An MTT assay demonstrates this modified PEDOT has good adhesion, cell viability and proliferation, similar to pristine PEDOT. This indicates that the modification process does not restrain the good biocompatibility of pristine PEDOT, which results from the doping of highly biocompatible N-rGO by this green method. The wrinkled structure, residual oxygen containing functional groups and dopant N atoms of N-rGO lead to the formation of a fluctuating surface and an increase in the hydrophilicity of PEDOT, which increase the specific surface area and cell adhesion in cell culture, respectively. Consequently, this modified PEDOT improves the electrochemical properties, and resolves the exfoliation and fragmentation problems of pristine PEDOT, while still retaining the high biocompatibility of pristine PEDOT, which is promising for a bio-electrode coating material. [ABSTRACT FROM AUTHOR]

Quercetin (QR), abundant in plants, is used to treat colitis and gastric ulcer and is also a promising anticancer agent. To quantificationally detect QR, a sensitive electrochemical sensor was fabricated by palladium nanoparticles loaded on carbon sphere @ molybdenum disulfide nanosheet core-shell composites (Cs@MoS2-Pd NPs). The Cs@MoS2-Pd NPs worked to remedy the shortcomings of MoS2 and exhibited good catalytic activity to QR. The oxidation reaction of QR on Cs@MoS2-Pd NPs/GCE involved two electrons and two protons. Furthermore, the molecular surface for electrostatic potential, Laplacian bond order, and Gibbs free energy were computationally simulated to speculate the order and site of the oxidation of QR. The results showed that the 4′ O–H and 3′ O–H broke successively during the oxidation reaction. When the concentration of QR was within 0.5 to 12 μM, the fabricated sensor could achieve linear detection, and the detection limit was 0.02 μM (S/N = 3). In addition, the sensor possessed good selectivity, repeatability, and stability, which has a broad prospect in practical application. [ABSTRACT FROM AUTHOR]

Abstract: Mobile counter anion exchange of electropolymerized polyaniline (PANI) films with the anions in acid solutions has been investigated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), scanning electron microscopy, Raman, UV–vis, and fluorescence spectra. The studied acids include camphorsulfonic acid, p-toluene sulfonic acid, HCl, HClO4, H2SO4 and H3PO4. In two cases of small and large counter ions of PANI films, CV tests have been performed alternately three times in each of two electrolytes containing organic or inorganic acid. The investigation of electrochemical and spectrophotometric measurements reveals that large counter anions can be easily replaced by the small anions; and the reverse exchange also occurs, but shows very low efficiency. This indicates that the achieved anion exchange in both cases leads to the remarkable alteration in electrochemical behavior and electrical conductance of PANI films. This implies counter anions, whatever the original or redoping ones, play an important role in the electrical, electrochemical, even optical properties of PANI. However, the polymer morphology does not be changed after exchange tests. This allows us to point out a ‘morphology-memory’ effect which is very significant for the development and application of PANI films with the same morphology and different properties. [Copyright &y& Elsevier]

Heterostructured composites, inheriting the integrated properties of the individual components due to the synergistic effect, have engendered great attention in materials science and energy storage. However, conventional biphasic heterostructures not only optimize the performance of the composites but also aggregate the inevitable drawbacks, which can be addressed with the construction of the triphasic heterostructures by introducing an appropriate intermediate phase, significantly. Herein, a two‐dimensional (2D) double‐heterostructures MoSe2‐TiO2‐MXene anode is architected for Li‐ion storage, which combines the advantages of the high theoretical capacity of MoSe2 and metallic conductivity of MXene. Besides, the in‐situ derived TiO2 can alleviate the irreversible phase transition of MoSe2, arising from the low electronic/ionic conductivities, through electronic coupling effects. Meanwhile, the intermediate phase of TiO2 can further prevent the restacking issue of MXene, thus sustaining its high conductivity. Finally, the three‐dimensional (3D) printing technology is employed to further improve the kinetics of the electrodes for Li‐ion capacitors (LICs), which deliver the power density of 5563 W kg−1 at an energy density of 51 Wh kg−1, and a remarkable cycling stability for 20 000 cycles at 1 A g−1. This work deepens the understanding of the influence of heterostructured engineering on the design of high‐energy/power storage devices. [ABSTRACT FROM AUTHOR]