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The anode‐cathode interplay is an important but rarely considered factor that initiates the degradation of aqueous zinc ion batteries (AZIBs). Herein, to address the limited cyclability issue of V‐based AZIBs, Al2(SO4)3 is proposed as decent electrolyte additive to manipulate OH−‐mediated cross‐communication between Zn anode and NaV3O8 ⋅ 1.5H2O (NVO) cathode. The hydrolysis of Al3+ creates a pH≈0.9 strong acidic environment, which unexpectedly prolongs the anode lifespan from 200 to 1000 h. Such impressive improvement is assigned to the alleviation of interfacial OH− accumulation by Al3+ adsorption and solid electrolyte interphase formation. Accordingly, the strongly acidified electrolyte, associated with the sedated crossover of anodic OH− toward NVO, remarkably mitigate its undesired dissolution and phase transition. The interrupted OH−‐mediated communication between the two electrodes endows Zn||NVO batteries with superb cycling stability, at both low and high scan rates. [ABSTRACT FROM AUTHOR]

Aqueous Zn||vanadium oxide batteries (ZVBs) have recently received considerable attention owing to their high capacity, safety, environmental friendliness, and cost effectiveness. However, the limited cycling stability caused by the irreversible dissolution in traditional aqueous electrolytes still restricts their further application. Herein, a novel 3 m Zn(CF3SO3)2 electrolyte with a mixture solvent of propylene carbonate (PC) and H2O is adopted for aqueous vanadium‐based zinc‐ion batteries. With the manipulation of the electrolyte solvation structure, the optimized P20 (20% PC in volume ratio) electrolyte enables super‐stable cycling performance with high‐capacity retention of 99.5%/97% after 100/1000 cycles at 0.1/5 A g−1 at ambient environment in the Zn||NaV3O8·1.5H2O batteries. Systematical electrochemical testing and characterizations illustrate the addition of PC effectively reduces the active water molecule in Zn2+‐solvent cations and H+ in the electrolyte, thereby suppressing the cathode dissolution caused by the inserted H+ and co‐inserted H2O during the discharge/charge process. Impressively, the PC addition also enabled the Zn||NaV3O8·1.5H2O batteries present high specific capacity of 183/168 mAh g‐1 and high‐capacity retention of 100%/100% over 300/400 cycles at 0.1/0.2 A g‐1 at −40 °C, thus efficiently broadening the practical application for ZVB. This research may provide a promising strategy for designing high‐performance electrolytes for aqueous vanadium‐based batteries. [ABSTRACT FROM AUTHOR]

Sodium‐ion batteries have attracted interest as an alternative to lithium‐ion batteries because of the abundance and cost effectiveness of sodium. However, suitable anode materials with high‐rate and stable cycling performance are still needed to promote their practical application. Herein, three‐dimensional Na2Ti3O7 nanowire arrays with enriched surface vacancies endowed by phosphorus doping are reported. As anodes for sodium‐ion batteries, they deliver a high specific capacity of 290 mA h g−1at 0.2 C, good rate capability (50 mA h g−1at 20 C), and stable cycling capability (98 % capacity retention over 3100 cycles at 20 C). The superior electrochemical performance is attributed to the synergistic effects of the nanowire arrays and phosphorus doping. The rational structure can provide convenient channels to facilitate ion/electron transport and improve the capacitive contributions. Moreover, the phosphorus‐doping‐induced surface vacancies not only provide more active sites but also improve the intrinsic electrical conductivity of Na2Ti3O7, which will enable electrode materials with excellent sodium storage performance. This work may provide an effective strategy for the synthesis of other anode materials with fast electrochemical reaction kinetics and good sodium storage performance. [ABSTRACT FROM AUTHOR]

Abstract: With the rapidly growing demand for low‐cost and safe energy storage, the advanced battery concepts have triggered strong interests beyond the state‐of‐the‐art Li‐ion batteries (LIBs). Herein, a novel hybrid Li/Na‐ion full battery (HLNIB) composed of the high‐energy and lithium‐free Na3V2(PO4)2O2F (NVPOF) cathode and commercial graphite anode mesophase carbon micro beads is for the first time designed. The assembled HLNIBs exhibit two high working voltage at about 4.05 and 3.69 V with a specific capacity of 112.7 mA h g−1. Its energy density can reach up to 328 W h kg−1 calculated from the total mass of both cathode and anode materials. Moreover, the HLNIBs show outstanding high‐rate capability, long‐term cycle life, and excellent low‐temperature performance. In addition, the reaction kinetics and Li/Na‐insertion/extraction mechanism into/out NVPOF is preliminarily investigated by the galvanostatic intermittent titration technique and ex situ X‐ray diffraction. This work provides a new and profound direction to develop advanced hybrid batteries. [ABSTRACT FROM AUTHOR]

The ionic liquids used herein were alkyl-containing ammonium-aluminum chloride ionic liquids system, which were made by the reaction of short-chain alkyl ammonium salts and aluminum chloride. The factors influencing stability of gasoline and the importance of improving it were described in this article, so was the characteristic of ionic liquids. A novel way to improve the stability of gasoline using ionic liquids was studied herein, as well as the study of decreasing the basic nitrogen content and the sulfur content of mercaptan, treating the gasoline and decreasing the olefin content of gasoline with supported ionic liquids catalyst on a small scale. After treating, the sulfur content of gasoline decreased to 0 nearly, and the basic nitrogen content decreased greatly too, whereas the octane number (RON) of gasoline increased a little. To improve the catalysis of ionic liquids and prolong the using life of ionic liquids, a buffering agent was added into ionic liquids. Ionic liquids catalyst, as a green catalyst friendly to environment, can displace many other alkylation catalysts, decrease the olefin content of gasoline, and show their notable advantages: mild conditions, short reaction time, simple operation, easy separation of the products and the catalyst. [ABSTRACT FROM AUTHOR]

Transition metal selenides have been attracting significant attention owing to their high conductivity and theoretical capacity. In this article, the N‐doped carbon (NDC)‐coated Ni1.8Co1.2Se4 nanoparticles encapsulated in NDC nanoboxes are prepared from the bi‐metal organic framework (Ni3[Co(CN)6]2·6H2O, Ni‐Co BMOF) after the selenization reaction and carbon coating. When used as an anode material for sodium‐ion batteries, the prepared anode material delivers excellent rate performance (211 and 153 mA h g−1 at ultrahigh current densities of 30 and 50 A g−1, respectively) and good cycling performance (379.3 mA h g−1 at 0.5 A g−1 after 100 cycles). More importantly, it also exhibits superior sodium‐ion full cell (SIFC) performance when coupled with a high‐voltage Na3V2(PO4)2O2F cathode recently self‐made by the authors. The fabricated SIFC gives an energy density up to 227 W h kg−1 and the capacity retention of above 97.6% even after 60 cycles at 0.4 A g−1 in a voltage range of 1.2–4.3 V at 25 °C. Moreover, the low‐temperature (from 25 to −25 °C) Na‐storage performance of the fabricated SIFC is also studied. An advanced anode material with outstanding high‐rate and low‐temperature properties is developed for sodium‐ion half/full batteries. In it, there exists a 3D conductive network composed of N‐doped dual carbon (NDDC) and abundant void spaces between NDDC and Ni1.8Co1.2Se4 nanoparticles, acting as not only a highway to achieve fast charge transfer but also an effective protector for active Ni1.8Co1.2Se4 material. [ABSTRACT FROM AUTHOR]

Abstract Developing efficient synthetic strategies to construct luminescent MOF materials combined triazolate and tetracarboxylate linkers are still great challenges. In this work, by employing a mixed ligand strategy, a new luminescent Zn-MOF based on mixed carboxylate-azolate ligands was synthesized through a DMF/DMSO system, namely, {Zn6(ABTC)2(TRZ)4(H2O)4(DMSO)2} (MOF1) (ABTC4- = 3,3′,5,5′-azobenzenetetracarboxylate, TRZ− = 1,2,4-triazole). In this framework, two types of inorganic SBUs and two different conformations of ABTC4− ligands assemble into a 3D framework with three different types of open channels. More importantly, MOF1 exhibits a strong blue luminescence property in the solid state at room temperature. [ABSTRACT FROM AUTHOR]

Sodium-ion batteries have attracted interest as an alternative to lithium-ion batteries because of the abundance and cost effectiveness of sodium. However, suitable anode materials with high-rate and stable cycling performance are still needed to promote their practical application. Herein, three-dimensional Na 2 Ti 3 O 7 nanowire arrays with enriched surface vacancies endowed by phosphorus doping are reported. As anodes for sodium-ion batteries, they deliver a high specific capacity of 290 mA h g -1 at 0.2 C, good rate capability (50 mA h g -1 at 20 C), and stable cycling capability (98 % capacity retention over 3100 cycles at 20 C). The superior electrochemical performance is attributed to the synergistic effects of the nanowire arrays and phosphorus doping. The rational structure can provide convenient channels to facilitate ion/electron transport and improve the capacitive contributions. Moreover, the phosphorus-doping-induced surface vacancies not only provide more active sites but also improve the intrinsic electrical conductivity of Na 2 Ti 3 O 7 , which will enable electrode materials with excellent sodium storage performance. This work may provide an effective strategy for the synthesis of other anode materials with fast electrochemical reaction kinetics and good sodium storage performance., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Due to the Earth's scarcity of lithium, replacing lithium with earth-abundant and low-cost sodium for sodium-ion batteries (SIBs) has recently become a promising substitute for lithium-ion batteries. However, the shortage of appropriate anode materials limits the development of SIBs. Here, a dual-carbon conductive network enhanced GeP 5 (GeP 5 /acetylene black/partially reduced graphene oxide sheets (GeP 5 /AB/p-rGO)) composite is successfully prepared by a facile ball milling method. The dual-carbon network not only provides more transport pathways for electrons but also relaxes the huge volume change of the electrode material during the charge/discharge process. Compared with only AB- or GO-modified GeP 5 (GeP 5 /AB or GeP 5 /GO) composite, the GeP 5 /AB/p-rGO composite shows a superior sodium storage performance with an excellent rate and cycle performance. It delivers a high reversible capacity of 597.5 and 175 mAh/g at the current density of 0.1 and 5.0 A/g, respectively. Furthermore, at the current density of 0.5 A/g, the GeP 5 /AB/p-rGO composite shows the reversible capacity of 400 mAh/g after 50 cycles with a little capacity attenuation. All above results prove that the GeP 5 /AB/p-rGO composite has a good prospect of application as an anode material for SIBs.

In this work, a flexible and self-supporting P-doped carbon cloth (FPCC), which is composed of interwoven mesh of hollow microtubules with porous carbon walls, is prepared via a vacuum-sealed doping technology by employing the commercially available cotton cloth as sustainable and scalable raw material. When directly used as binder-free anode for sodium-ion batteries, the as-prepared FPCC delivers superior Na-storage properties in terms of specific capacity up to 242.4 mA h g -1 , high initial Coulombic efficiency of ∼72%, excellent rate capabilities (e.g., 123.1 mA h g -1 at a high current of 1 A g -1 ), and long-term cycle life (e.g., ∼88% capacity retention after even 600 cycles). All these electrochemical data are better than the undoped carbon cloth control, demonstrating the significance of P-doping to enhance the Na-storage properties of cotton-derived carbon anode. Furthermore, the technologies of electrochemical impedance spectroscopy and galvanostatic intermittent titration technique are implemented to disclose the decrease of charge transfer resistance and improvement of Na-migration kinetics, respectively.