Zn metal has been considered as a promising anode material for rechargeable aqueous metal-ion batteries. However, the propensity of dendrite growth during plating restricts its practical applications. Herein we propose an effective, low-cost, and nontoxic electrolyte additive, tetrabutylammonium sulfate (TBA2SO4), as the first example of a cationic surfactant-type electrolyte additive in Zn-ion batteries, which can induce the uniform Zn deposition in both electrode preparation and the battery charge/discharge process. Electrochemical characterizations, in situ optical microscopy observation, along with density functional theory (DFT) calculations reveal the unique zincophobic repulsion mechanism, which results in the minimum addition amount of 0.029 g L–1 compared with other reported additives (at least 1g L–1), demonstrating the great potential for practical application. Excellent cycling performance with dendrite-free morphology at different current densities and discharge depths is achieved for both the symmetric cell and the full cell (coupled to α-MnO2) using the as-prepared 3D Zn anode and the proposed additives.

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Using synergetic effects of various sodium storage modes and materials to construct high power, high energy, and long cycling flexible sodium anode materials is significant and still challenging. Here, by advantageous functional integration of adsorption‐intercalation‐conversion sodium storage mechanisms, a 3D flexible fiber paper anode with the composition of Nb2O5@hard carbon@MoS2@soft carbon is designed and prepared. Based on the synergetic effects, it exhibits higher specific capacity than pure Nb2O5, with more excellent rate performance (245, 201, 155, 133, and 97 mAh g−1 at the current density of 0.2, 1, 5, 10, and 20 A g−1, respectively) than pure MoS2 as well as admirable long‐term cycling characteristics (≈82% capacity retention after 20 000 cycles at 5 A g−1). Relevant kinetics mechanisms are expounded in detail. This work can be helpful for preparing other types of hybrid and flexible electrodes for energy storage systems.

An inorganic-organic hybrid surfactant with a hexavanadate cluster as the polar head group was designed and observed to assemble into micelle structures, which further spontaneously coagulate into a 1D anisotropic structure in aqueous solutions. Such a hierarchical self-assembly process is driven by the cooperation of varied noncovalent interactions, including hydrophobic, electrostatic, and hydrogen-bonding interactions. The hydrophobic interaction drives the quick formation of the micelle structure; electrostatic interactions involving counterions leads to the further coagulation of the micelles into larger assemblies. This process is similar to the crystallization process, but the specific counterions and the directional hydrogen bonding lead to the 1D growth of the final assemblies. Since most of the hexavanadates are exposed to the surface, the 1D assembly with nanoscale thickness is a highly efficient heterogeneous catalyst for the oxidation of organic sulfides with appreciable recyclability.

Developing high power-high energy electrochemical energy storage systems is an ultimate goal in the energy storage field, which is even more difficult but significant for low-cost sodium ion batteries. Here, fluoride is successfully prepared by the electrostatic spray deposition (ESD) technique, which greatly expands the application scope of ESD. A twostep strategy (solvothermal plus ESD method) is proposed to construct a bicontinuous ordered network of 3D porous Na 3 (VO) 2 (PO 4 ) 2 F/reduced graphene oxide (NVOPF/rGO). This two-step strategy makes sure that NVOPF can be prepared by ESD, since it avoids the loss of F element during synthesis. The obtained NVOPF particles are as small as 15 nm, and the carbon content is only 3.5% in the final nanocomposite. Such a bicontinuous ordered network and small size of electroactive particles lead to the significant contribution of the pseudocapacitance effect to sodium storage, resulting in real high power-high energy sodium cathodes. The cathode exhibits excellent rate capability and cycling stability, whose rate performance is one of the best ever reported in both half cells and full cells. Moreover, this work provides a general and promising strategy for developing high power-high energy electrode materials for various electrochemical energy storage systems. Sodium Ion BatteriesThe ORCID identification number(s) for the author(s) of this article can be found under https://doi.

The development of cathode materials with high Li storage capacity and fast Li‐ion diffusion kinetics is considered to be a promising way to extend the energy and power densities of Li‐ion batteries (LIBs). As potential high‐capacity cathode materials for LIBs, polyoxometalates (POMs) suffer greatly from inherent drawbacks. Therefore, another possibility for the application of POMs in LIBs is shown, which is to transform POMs into relevant 3D porous Li‐containing oxides. Here, a unique 3D porous γ‐LiV2O5 film is successfully prepared by combining the electrostatic spray deposition technique and the POM as a precursor. Outstanding high capacity with stable cycling performance and excellent rate capability is realized based on 3D porous nanostructure and thin‐film morphology, which effectively facilitate the transport of both lithium ion and electron. Moreover, this work demonstrates the feasibility of achieving high‐performance metal oxide cathode by the transformation of POMs and also shows the superiority of γ‐phase over α‐phase as a starting cathode material in LIBs as well.

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An effective synthetic strategy for the amino-containing organic derivative of hexavanadate, TBA 2 ijV 6 O 13 {(OCH 2 ) 3 CNH 2 } 2 ], is presented. By using this method, the yield is increased extremely and crystals of the intermediate and cation-exchanged products are both obtained and structurally characterized via single-crystal X-ray diffraction, IR and 1 H-NMR.