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Gel polymer electrolytes (GPEs) are intrinsically advantageous over rigid inorganic ones due to their easy processability and scalability. However, in terms of poor mechanical strength, GPEs can hardly satisfy the requirement of practical Li metal batteries. Herein, a novel one‐dimensional Cu‐metal–organic framework (MOF)‐filler‐reinforced GPE with the merits of high mechanical strength and high ionic conductivity is developed. When such GPE is used in Li symmetrical cells, small and stable Li‐plating/stripping overpotentials (~50 mV) can be maintained over 350 h at.3 mA/cm2. Benefitting from the above MOF‐filler‐reinforced GPE, a full cell with the Li metal anode and LiFePO4 cathode presents a stable cycling performance with a low capacity decay rate of.004% per cycle over 800 cycles at 1 C. [ABSTRACT FROM AUTHOR]

Solid-state Li-ion batteries (SSBs) are believed the new future of electrochemical energy storage, while the solid electrolyte membrane is the core part. The development of new electrolyte membrane with easy densification, high stability and high conductivity is crucial for the widespread application of SSBs. In this study, tuning the conductivity and sintering behavior of perovskite-type La 2/3-x Li 3x TiO 3 (LLTO) membranes through a co-doping strategy was proposed and systematically investigated. Specifically, the membranes with the nominal compositions of Li 0.33-y+x La 0.557-x M x Ti 1-y N y O 3 (M = Sr, Ba, Ca, N = Ta) were designed and investigated. The results demonstrated that replacement of La3+ by smaller Ca2+ decreased the bulk Li+ conductivity while substitution of La3+ by Sr2+ or Ba2+ with larger ionic radii increased the bulk Li+ conductivity. Besides, Ta5+ and Sr2+ co-doped LLTO with optimized Ta/Sr molar ratio could improve the membrane densification involving the relative density and grain size. Accordingly, a high total Li+ conductivity (1.4 × 10−4 S cm−1) with low electronic conductivity (3.2 × 10−8 S cm−1) could be achieved, and the as-prepared Li 0.33 La 0.457 Sr 0.1 Ti 0.9 Ta 0.1 O 3 membrane presented prominent electrochemical performance with a high capacity retention (89%) and Coulombic efficiency of 97% for 80 cycles, thus promised co-doping strategy for developing superior perovskite Li-ion conducting membranes for SSBs. • Perovskite Li 0.33-y+x La 0.557-x M x Ti 1-y N y O 3 (M = Sr, Ba, Ca, N = Ta) membranes were prepared systematically. • Ta5+ and Sr2+ co-doped membrane exhibited high membrane densification and low grain boundary resistance. • Li 0.33 La 0.457 Sr 0.1 Ti 0.9 Ta 0.1 O 3 showed a total Li-ion conductivity of 1.4 × 10−4 S cm−1 at room temperature. • The membrane could be cycled in solid-state Li-ion battery with a capacity retention of 89% after 80 cycles. [ABSTRACT FROM AUTHOR]

• (Bi 2) m (Bi 2 Te 3) n nanotubular architectures were fabricated via the Kirkendall effect. • Tellurium precursor played a crucial role in the formation of nanoscale tubular structure. • (Bi 2) m (Bi 2 Te 3) n contains four custom-built composition of Bi 2 Te 3 , Bi 4 Te 3 , BiTe, and Bi 2 Te 3 -Te. • The results were verified by XRD, SEM, EDX, HR-TEM, SAED, and ICP-OES. The (Bi 2) m (Bi 2 Te 3) n series, as well-studied thermoelectric materials, have also attracted worldwide attention for their unique topological insulator property. However, only one of several compounds in the Bi-Te systems is synthesized, especially for one-dimensional structures. Herein, a two-step solvothermal process has been designed to synthesize nanotubular (Bi 2) m (Bi 2 Te 3) n series (i.e., Bi 2 Te 3 , Bi 4 Te 3 , BiTe, and Bi 2 Te 3 -Te) by optimizing the concentration of Bi agent and altering the microstructure of Te precursors during the reaction process regarding "Kirkendall effect". The results were verified by powder X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray spectroscope (EDS), high-resolution transmission electron microscope (HR-TEM), selected area electron diffraction (SAED), and inductively coupled plasma optical emission spectrometer (ICP-OES). A possible growth mechanism was proposed based on experimental results. This work provides a feasible way to selectively synthesize (Bi 2) m (Bi 2 Te 3) n compounds with tunable composition and structure. [Display omitted]. [ABSTRACT FROM AUTHOR]

Overall, the articles selected for publication in this special issue encompass a wide range of research topics related to deep learning for fuel cells and batteries according to both theoretical calculations and experimental results. Fuel cells and batteries, as two key types of energy conversion and storage devices, have recently attracted more and more attention. This special issue contains 14 contributions, including 11 research articles and 3 reviews, contributed from the experts working in the fields of fuel cells and batteries. [Extracted from the article]

Abstract: We demonstrate a promising method to fabricate highly adhesive silver nanoparticle coating on glass carbon electrode with good dispersity by using gas phase cluster beam deposition. The fabricated nanoparticles have clean surface and show enhanced electrocatalytic activity toward the reduction of H2O2 with a considerably decreased overpotential. A nonenzyme sensing platform for stable detection of H2O2 with a very rapid response time (less than 1s), high sensitivity (63μA/mM) as well as a low detection limit (1.3μM) is realized from the silver nanoparticle based electrode with a optimized nanoparticle coverage. [Copyright &y& Elsevier]

Abstract: Few-layer graphene sheets were prepared by splitting expanded graphite using high-power sonication. Atomic-level calibrated scanning transmission electron microscopy was used to obtain efficient layer statistics, enabling optimization of the experimental conditions. This resulted in a two-step splitting mechanism in which the mean number of layers was first reduced to less than 20 by heating to 1100°C and then to a few-layer region by a 5-min104 WL−1 – power-density sonication. Raman spectroscopic analysis confirms the above mechanism and demonstrates that the sheets are largely free of defects and functional groups. [Copyright &y& Elsevier]

Abstract: In this paper, we reported the successful synthesis of hierarchical Ni11(HPO3)8(OH)6 superstructures based on nanorods via a facile hydrothermal route, employing NiCl2·6H2O and NaH2PO2·H2O as the reactants in the presences of polyvinylpyrrolidone (PVP) and CH3COONa·3H2O. The reaction was carried out at 170°C for 10h. HPO3 2− ions were provided via the dismutation reaction of H2PO2 − ions in a weak basic solution. The as-obtained products were characterized by X-ray powder diffraction (XRD), energy dispersive spectrometry (EDS), field emission scanning electron microscopy (SEM), selected area electron diffraction (SAED) and high resolution transmission electron microscopy (HRTEM). Some factors influencing the morphology of the hierarchical Ni11(HPO3)8(OH)6 nanorods, such as the reaction temperature, time, the amounts of PVP and CH3COONa, and the initial concentration of Ni2+ ions, were systematically investigated. A possible growth mechanism was proposed based on experimental results. [Copyright &y& Elsevier]

Rigid‐flexible coupled composite polymer electrolytes (CPEs, e.g., polyethylene oxide/Li6.4La3Zr1.4Ta0.6O12, PEO/LLZTO) hold the promise of integrating the respective merits of organic polymer electrolyte and inorganic ceramic fillers to achieve better all‐solid‐state batteries (ASSBs), but commonly suffer from poor synergistic effect owing to the ionically/electronically resistive layer on the ceramic surface. Representatively, the Li2CO3 passivation layer‐isolated LLZTO not only contributes minimally to the Li+ conduction in PEO/LLZTO CPE, but also narrows the available electrochemical window. Herein, an interfacial reconstruction strategy is disclosed based on mild liquid‐phase chemical reaction and subsequent self‐assembly, allowing the detrimental Li2CO3 to fully react with succinic anhydride (SA), and simultaneously constructing a robust ultra‐thin lithium succinate (SALi) ionic conductor shell to eradicate its regeneration. Accordingly, the obtained PEO/LLZTO@SALi (PLS) CPE shows a high room‐temperature ionic conductivity (1.2 × 10−4 S cm−1), a wide electrochemical window (4.8 V), a notable Li+ transference number (0.37), as well as nonflammability and exceptional compatibility with Li metal in Li/Li symmetric cells (2000 h at 0.2 mA cm−2). More encouragingly, the Li/PLS CPE/LiFePO4 full ASSB maintains an ultrahigh capacity retention of 84.3% after 1400 cycles at room temperature. This work propels the design of high‐performance CPEs through the interfacial modulation of inorganic ceramic fillers. [ABSTRACT FROM AUTHOR]

Abstract Poor electrical conductivity of sulfur, sluggish redox kinetics, dissolution of intermediate polysulfides, and expansion in volume upon cycling are the main drawbacks that hamper the practical application of Li-S batteries. By taking advantages of the high conductivity and favorable catalytic activity of RuO 2 , we design a 3D carbon nanotube film with embedded RuO 2 nanoparticles as a freestanding type of chemisorptive and catalyst-like cathode for Li-S batteries, which can be facilely prepared by a surfactant-assisted vacuum infiltration method. Both experimental and theoretical results reveal the excellent capability of RuO 2 for anchoring polysulfides and accelerating the kinetics of polysulfides catalytic redox reactions. Besides, the 3D freestanding cathode is beneficial to overcoming pulverization during volume changes, especially for long-term cycling. At a high areal sulfur loading of 2 mg cm−2, favorable initial capacities of 750 and 1060 mA h g−1 respectively at 2 and 0.5 C are achieved. More attractively, the capacity after 1000 cycles maintains 405 mA h g−1 at 0.5 C with a loss in capacity of only 0.06% per cycle. Additionally, such freestanding cathode allows the batteries to be tested under various bending stages, hence encouraging more research works on fabrication of other 3D nanostructure families as high-performance cathodes for Li-S batteries. Graphical abstract A 3D free-standing catalyst-like cathode is designed and prepared for Li-S battery through a surfactant-assisted infiltration approach. Favorable high-rate performances and stabilities are delivered for Li-S battery with the as-prepared cathode due to the excellent chemisorption, high conductivity and for various redox reactions of RuO 2. The 3D free-standing catalyst-like cathode provides an inspirational model for promising flexible energy storage devices. Image 1 Highlights • A free-standing porous RuO 2 -embedded 3D CNT film is fabricated. • The freestanding film can overcome the pulverization of sulfur cathode. • Conductive RuO 2 shows favorable catalytic activity for polysulfides. • The cross-linked CNT enables the electron transport in whole cathode. • The Li-S battery with the freestanding cathode operates over 1000 cycles. [ABSTRACT FROM AUTHOR]

The increasing demand for energy, coupled with the continuing deterioration of the environment, has heightened people's desire for renewable energy storage technologies, such as rechargeable zinc‐air batteries (ZABs). However, the race for the developing ZABs usually focuses on the search for new materials, with less emphasis on electrode engineering and recycling. Herein, for the first time, a simple, scalable, and inexpensive electrode engineering and recycling strategy for ZABs is proposed based on the magnetic binder engineering of the cobalt‐implanted electrocatalysts. By manipulating the electrode with magnets, the ZAB can cycle for 1200 h (7200 cycles), and its anti‐pulverization behavior is revealed through in situ observation of a visual cell with an air electrode in the charged state. Moreover, the cobalt‐implanted electrocatalysts can be recycled from the spent ZABs using a magnetic force‐separation method. Additionally, the ZAB with the recycled electrocatalyst exhibits considerably prolonged cycling stability for over 500 h (ΔE = 0.86 V). This study not only enables the design of magnetic force‐engineered electrodes with improved battery performance but also provides sustainable solutions for recycling electrocatalysts for many possible applications beyond ZABs. [ABSTRACT FROM AUTHOR]

Garnet‐based solid‐state Li‐metal batteries (GSSBs) have the merits of high energy density and high safety. However, the realization of a stable and well‐matched Li|garnet interface for GSSBs remains challenging due to electron leakage and lithiophobic Li2CO3 impurity. To address these issues, herein, new surface chemistry is reported that converts the undesired Li2CO3 contaminant into an ultra‐thin lithium polyphosphate (Li‐PPA) layer through anhydrous polyphosphoric acid ‐induced in situ substitution reaction without damaging the water‐sensitive garnet electrolyte. In particular, the Li‐PPA interlayer not only facilitates the homogenous spreading of molten Li but also creates a robust electron‐blocking shield to suppress Li dendrite formation. As a result, the assembled Li symmetric cell exhibits a low interfacial impedance (4 Ω cm2) and high critical current density (1.8 mA cm−2) at 25 °C, which enables the cell to continuously cycle over 2500 h at 0.2 mA cm−2. Furthermore, the GSSBs paired with LiFePO4 deliver a high capacity of 149.3 mAh g−1 at 1 C and maintain 92.3% of the initial capacity after 500 cycles and can be used for solar energy storage, suggesting the feasibility of this interfacial engineering strategy for GSSBs. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we report the successful synthesis of Ni12P5 hollow spheres via a facile hydrothermal route, employing white phosphorus (WP) and nickel nitrate as the reactants in the presence of hexamethylenetetramine (HMT) and polyethylene glycol 10000 (PEG-10000). The phase and morphology of the product were characterized by means of powder X-ray diffraction (XRD), energy dispersive spectrometry (EDS), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). HMT and surfactant (PEG-10000) played important roles in the formation of Ni12P5 hollow microspheres. Furthermore, research also showed that the as-prepared Ni12P5 hollow spheres could photocatalytically degrade some organic dyes such as Safranine T and Pyronine B under irradiation of 365 nm UV light. [Copyright &y& Elsevier]

All‐solid‐state lithium batteries (ASSBs) have the potential to trigger a battery revolution for electric vehicles due to their advantages in safety and energy density. Screening of various possible solid electrolytes for ASSBs has revealed that garnet electrolytes are promising due to their high ionic conductivity and superior (electro)chemical stabilities. However, a major challenge of garnet electrolytes is poor contact with Li‐metal anodes, resulting in an extremely large interfacial impedance and severe Li dendrite propagation. Herein, an innovative surface tension modification method is proposed to create an intimate Li | garnet interface by tuning molten Li with a trace amount of Si3N4 (1 wt%). The resultant Li‐Si‐N melt can not only convert the Li | garnet interface from point‐to‐point contact to consecutive face‐to‐face contact but also homogenize the electric‐field distribution during the Li stripping/depositing process, thereby significantly decreasing its interfacial impedance (1 Ω cm2 at 25 °C) and improving its cycle stability (1000 h at 0.4 mA cm−2) and critical current density (1.8 mA cm−2). Specifically, the all‐solid‐state full cell paired with a LiFePO4 cathode delivered a high capacity of 145 mAh g−1 at 2 C and maintained 97% of the initial capacity after 100 cycles at 1 C. [ABSTRACT FROM AUTHOR]

Considering significant safety advantages, all solid-state LIBs have attracted considerable attentions as alternative power sources for electric vehicles where safety is a big concern, while the development of solid electrolyte membrane with high lithium-ion conductivity, negligible electron conductivity and high stability is the key challenge. Here, Sr and Sb co-doping strategy was applied to further improve the sintering capability and conductivity properties of Li 7 La 3 Zr 2 O 12 garnet-type electrolytes. Specifically, Li 6.6+x La 3-x Sr x Zr 1.6 Sb 0.4 O 12 (x = 0–0.2) oxides were designed and the physical and electrochemical performance of the various materials were comparatively studied. The results of X-ray diffraction and Raman spectra revealed Li 6.6+x La 3-x Sr x Zr 1.6 Sb 0.4 O 12 (x = 0–0.2) prepared by conventional solid-state reaction was in cubic structure. The introduction of a small amount of Sr into the La sites is beneficial for membrane densification and lithium-ion mobility, turning out high density of 95.1% and ionic conductivity of 8.83 × 10−4 S cm−1 at room temperature. The EIS showed the doping of Sr in La sites resulted in improved conductivity at both grain boundary and the oxide bulk. The batteries consisting of lithium film anode, Li 6.66 La 2.94 Sr 0.06 Zr 1.6 Sb 0.4 O 12 solid electrolyte membrane and LiFePO 4 cathode reached the first discharge capacity of 157 mAh g−1 at 0.1 C between 4.2 and 2.0 V (vs. L/Li+) with capacity retention of 93% after 100 cycles at ambient temperature. These results displayed that the Sr, Sb co-doped LLZO electrolytes are alternative for all solid-state Li-ion batteries. Image 1 • A Sr, Sb co-doping strategy was used to design Li 7 La 3 Zr 2 O 12 electrolyte membrane. • A new garnet-type Li 6.66 La 2.94 Sr 0.06 Zr 1.6 Sb 0.4 O 12 (LLSZSO) membrane was developed. • The LLSZSO shows high ionic conductivity of 8.83 × 10−4 S cm−1 at room temperature. • The capacity of LLSZSO is 146 mAh g−1 with retention rate of 93% after 100 cycles. [ABSTRACT FROM AUTHOR]

Abstract Considering the abundant sodium resources, sodium-ion batteries (SIBs) demonstrate great potential in large-scale electrochemical energy storage sectors which capacity and cycle stability is highly dependent on their electrode materials. Layered P2-type Mn-Fe-based oxide has been considered as one of the most promising cathodes for SIBs, while its unsatisfactory cycle performance and low energy density strongly limit practical application. Here, a Co/Ni modification strategy is proposed to optimize P2-Na 2/3 Mn 1/2 Fe 1/2 O 2 (MF) from both aspects of reversible capacity and cycle stability, leading to the design of a new P2-Na 2/3 Mn 1/2 Fe 1/4 Co 1/8 Ni 1/8 O 2 (MFCN). In this new layered P2-type material, the introduction of Co effectively inhibits the irreversibility of the material, and the introduction of Ni relieves the Jahn-Teller effect and reduces Mn dissolution. The simultaneous introduction of Co and Ni effectively improves the cycle stability of the electrode, indicated by the increase of the capacity retention rate from 51.5% for MF to 87.4% for MFCN over 100 discharge-charge cycles at the same current density of 130 mA g−1. Meanwhile, the introduction of Ni effectively increases the discharge voltage with the middle discharge voltage increasing from 2.8 V (MF) to 3.3 V (MFCN), thereby improving the energy density of the electrode. All above features make the new material highly promising for use as a cathode material in practical SIBs. Graphical abstract Image 1 Highlights • A co-doping strategy was used to design P2-type layered oxide. • A new P2-type layered oxide Na 2/3 Mn 1/2 Fe 1/4 Co 1/8 Ni 1/8 O 2 (MFCN) was developed. • The capacity retention rate of MFCN was 87.4% at 130 mA g−1 after 100 cycles. • The middle discharge voltage increased from 2.8 V (Na 2/3 Mn 1/2 Fe 1/2 O 2) to 3.3 V (MFCN). [ABSTRACT FROM AUTHOR]

A sol-gel method with ethylene diamine tetraacetic acid and citric acid as co-chelates is employed for the synthesis of P2-type Na 2/3 Mn 1/2 Fe 1/4 Co 1/4 O 2 as cathode material for sodium-ion batteries. Among the various calcination temperatures, the Na 2/3 Mn 1/2 Fe 1/4 Co 1/4 O 2 with a pure P2-type phase calcined at 900 °C demonstrates the best cycle capacity, with a first discharge capacity of 157 mA h g −1 and a capacity retention of 91 mA h g −1 after 100 cycles. For comparison, the classic P2-type Na 2/3 Mn 1/2 Fe 1/2 O 2 cathode prepared under the same conditions shows a comparable first discharge capacity of 150 mA h g −1 but poorer cycling stability, with a capacity retention of only 42 mA h g −1 after 100 cycles. Based on X-ray photoelectron spectroscopy, the introduction of cobalt together with sol-gel synthesis solves the severe capacity decay problem of P2-type Na 2/3 Mn 1/2 Fe 1/2 O 2 by reducing the content of Mn and slowing down the loss of Mn on the surface of the Na 2/3 Mn 1/2 Fe 1/4 Co 1/4 O 2 , as well as by improving the activity of Fe 3+ and the stability of Fe 4+ in the electrode. This research is the first to demonstrate the origin of the excellent cycle stability of Na 2/3 Mn 1/2 Fe 1/4 Co 1/4 O 2 , which may provide a new strategy for the development of electrode materials for use in sodium-ion batteries. [ABSTRACT FROM AUTHOR]

Before the practical application of the Li–O 2 battery (LOB), a critical issue regarding large overpotential upon charging (which causes irreversible side reactions and low energy efficiency) should be resolved. The utilization of redox mediators (RMs) which oxidatively decompose insulating discharge product, Li 2 O 2 , is one promising solution to address this issue. However, the soluble RMs can easily diffuse to and react with the Li metal anode (encountering Li dendrites is even worse). Here, a chemical self-assembly strategy is introduced into the fabrication of the iodide-redox-phobic and Li-ion-philic membrane for LOBs, in which the electronegative δ-MnO 2 layer is in-situ grown on commercial polyethylene (PE) membrane (MnO 2 @PE). The electronegative MnO 2 layer can simultaneously repel the shuttle of iodide species and regulate the uniform Li + deposition. Controlling cut-off capacity of 1000 mAh g−1, iodide-redox-based LOB with MnO 2 @PE demonstrates low overpotentials (∼0.7 V vs. Li+/Li), dendrite-suppressing capability, as well as impressive long-term reversibility over 500 cycles (2000 h), which urges the LOB technology competitive among the next-generation rechargeable power systems. [Display omitted] • The δ-MnO 2 -based membrane with iodide-redox-phobic and Li-ion-philic characters has been prepared. • In situ constructed δ-MnO 2 layer on polyethylene membrane (MnO 2 @PE) is highly flexible and tightly linked. • The electronegative MnO 2 @PE membrane can simultaneously suppress the iodide-redox shuttle and Li dendrite growth. • Li–O 2 battery with MnO 2 @PE membrane shows long-term reversibility over 500 cycles (2000 h) with a small overpotential. [ABSTRACT FROM AUTHOR]

Hierarchically porous, metallic RuO2 hollow spheres are applied as a carbon‐free cathode for Li–O2 batteries for the first time. They exhibit low charge potentials of ≈3.5 V, corresponding to overpotentials of 0.13/0.54 V in discharging and charging processes, a large reversible capacity of ≈1400 mAh g−1, and 100 cycles of full discharge and charge. [ABSTRACT FROM AUTHOR]

[Display omitted] • Contact issue of the anode-electrolyte interface was tackled by a Li-Mo composite. • Lower cohesive energy and higher binding energy are beneficial to better contact. • Symmetric cell shows a high critical current density and a stable 1200-h cycling. • A full cell with a LiFePO 4 cathode presented stable performance for 200 cycles. • The work provides a facile and feasible way to overcome interface problems. Interface issues are the biggest challenges that hindering the commercialization of solid-state lithium metal batteries (SSLMBs). Here, we propose a novel strategy targeting for effectively resolving the tedious lithium-garnet solid electrolyte interface problem from the lithium side. We intentionally introduce α-MoO 3 nanobelts into the molten metallic lithium, forming a Li-Mo composite. Compared to molten lithium, the composite improves wettability on the garnet electrolyte. As revealed by density functional theory calculations, such improvement could be ascribed to the reduced cohesive energy and the improved interface binding energy to the LLZTO. Intimate surface contact can be easily achieved without complicated surface treatment, which not only significantly reduces the interface resistance to ~ 1 Ω cm2, but could also effectively inhibits the generation of lithium dendrites. These features ensure a significant critical current density of 1700 µA cm−2 and a stable electrochemical Li plating/stripping process for more than 1200 h. A full cell with the Li-Mo composite anode and LiFePO 4 cathode also presents a fairly stable cycling performance at room temperature. Different from most previous strategies that try to tackle the interface issues from the electrolyte side, our research results suggest that designing lithium composite anodes with low cohesive energy and high interface binding energy to the solid electrolyte is an attractive and feasible solution to overcome interface problems. [ABSTRACT FROM AUTHOR]

Antireflection TiO2 nanoparticle film was fabricated on silica glass substrate by using directed cluster beam deposition method. Self-shadowing becomes a dominant growth mechanism for nanoparticle deposition at sufficiently large incident angles, which results in extremely porous nanoparticle stacking and yields excellent control over the refractive index profile. Inclined columnar and porous microstructure was confirmed with SEM and AFM. The TiO2 nanoparticle films show ultra-high transmittance, broadband and omnidirectional characters, which can be attributed to its porous structure and modulated refractive index. We also found that the film displays an angular selective optical transmittance. The highest antireflection enhancement of the light transmission can be obtained for light incidence along the nanoparticle columns. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Abstract: Using porous cuprous oxide (Cu2O) microcubes, a simple non-enzymatic amperometric sensor for the detection of H2O2 and glucose has been fabricated. Cyclic voltammetry (CV) revealed that porous Cu2O microcubes exhibited a direct electrocatalytic activity for the reduction of H2O2 in phosphate buffer solution and the oxidation of glucose in an alkaline medium. The non-enzymatic amperometric sensor used in the detection of H2O2 with detection limit of 1.5×10−6 M over wide linear detection ranges up to 1.5mM and with a high sensitivity of 50.6μA/mM. This non-enzymatic voltammetric sensor was further utilized in detection of glucose with a detection limit of 8.0×10−7 M, a linear detection range up to 500μM and with a sensitivity of −70.8μA/mM. [Copyright &y& Elsevier]

The self‐catalyzed growth of nanostructures on material surfaces is one of the most time‐ and cost‐effective ways to design multifunctional catalysts for a wide range of applications. Herein, the use of this technique to develop a multicomponent composite catalyst with CoSx core encapsulated in an ultrathin porous carbon shell entangled with Co, N‐codoped carbon nanotubes is reported. The as‐prepared catalyst has a superior catalytic activity for oxygen evolution and oxygen reduction reactions, an ultralow potential gap of 0.74 V, and outstanding durability, surpassing most previous reports. Such superiority is ascribed, in part, to the unique 3D electrode architecture of the composite, which is favorable for transporting oxygen species and electrons and creates a synergy between the components with different functionalities. Moreover, the flexible solid Zn–air battery assembled with such an air electrode shows a steady discharge voltage plateau of 1.25 V and a round‐trip efficiency of 70% at 1 mA cm−2. This work presents a simple strategy to design highly efficient bifunctional oxygen electrocatalysts and may pave the way for the practical application of these materials in many energy conversion/storage devices. [ABSTRACT FROM AUTHOR]

Considering the abundance and low price of sodium, sodium-ion batteries (SIBs) are of particular attractiveness for large-scale electrochemical energy storage. Layered P2–Na 2/3 Mn 1/2 Fe 1/4 Co 1/4 O 2 (NMFC) is a promising cathode material for SIBs because of its large theoretical capacity, however, its high air sensitivity and poor cycling stability seriously limits the practical use. Here, we report nanometre-thick Al 2 O 3 coating of NMFC electrode through atomic layer deposition (ALD) technique can effectively alleviate such deficiencies to obtain an air-insensitive electrode, which was realized by effectively preventing the direct exposure of NMFC to H 2 O and CO 2 present in the air atmosphere. Interestingly, the ultrathin Al 2 O 3 coating did not cause a block for sodium ion intercalation, and a high capacity of 217.9 mA h g−1 at a high cut-off potential of 4.5 V was achieved. More attractively, a capacity retention rate as high as 84.8% was obtained after cycling at a current density of 0.5C over 100 cycles, demonstrating improved electrochemical stability. Based on CV and EIS characterizations, such good cycling stability is associated with the use of the Al 2 O 3 coating layer as well, which effectively avoided the side reactions at the interface of the liquid electrolyte and the active material under high potential. Display Omitted • Layered P2-type Na 2/3 Mn 1/2 Fe 1/4 Co 1/4 O 2 (NMFC) oxide was synthesized by solid-state method. • Ultrathin Al 2 O 3 layer was successfully coated on NMFC by atomic layer deposition. • The air sensitivity of NMFC was reduced. • The cycling stability of NMFC was improved. [ABSTRACT FROM AUTHOR]