Aqueous Zn‐metal batteries (AZMBs) are promising candidates for next‐generation energy storage. For achieving highly reversible Zn anodes by controlling interfacial Zn 2+ diffusion, the targeted exploration of electrolyte additives is crucial. Conventional additives typically exhibit strong coordination with Zn 2+ , which mitigates concentration polarization for planar deposition, but can also cause Zn 2+ retention and uneven dissolution during stripping. This study introduces weakly coordinating additives to achieve a balanced regulation of Zn plating and stripping. By investigating a series of para‐substituted phenols, it is demonstrated that weakly coordinating phenolic additives retain the ability to concentrate solvated [Zn(H 2 O) 6 ] 2+ at the interface, thereby mitigating concentration polarization. Both experimental and computational results confirm that the reduced coordination strength enhances interfacial Zn 2 ⁺ mobility, ensuring a uniform Zn 2+ distribution at the electrode–electrolyte interface. Among the investigated additives, the p‐hydroxyacetophenone (ACETO) exhibits optimal performance, enabling ZnǁZn symmetric cells to achieve an exceptional cycling stability (1281 h at 5 mA cm −2 and 5 mAh cm −2 ) and a high‐rate capability. Furthermore, Zn ǁ I 2 batteries containing ACETO retain 89.5% of their capacity after 2700 cycles. This work establishes weakly coordinating additives as a viable strategy and provides a new design principle for regulating interfacial Zn 2 ⁺ dynamics.

A new type of sealed battery via the interconversion of LiO2/Li2O2 was developed on the basis of the stabilization of LiO2 on the OR-rGO cathode, and a long life of 700 cycles was achieved.

As a full cell system with attractive theoretical energy density, challenges faced by Li-O2 batteries (LOBs) are not only the deficient actual capacity and superoxide-derived parasitic reactions on the cathode side but also the stability of Li-metal anode. To solve simultaneously intrinsic issues, multifunctional fluorinated graphene (CFx, x = 1, F-Gr) was introduced into the ether-based electrolyte of LOBs. F-Gr can accelerate O2- transformation and O2--participated oxygen reduction reaction (ORR) process, resulting in enhanced discharge capacity and restrained O2--derived side reactions of LOBs, respectively. Moreover, F-Gr induced the F-rich and O-depleted solid electrolyte interphase (SEI) film formation, which have improved Li-metal stability. Therefore, energy storage capacity, efficiency, and cyclability of LOBs have been markedly enhanced. More importantly, the method developed in this work to disperse F-Gr into an ether-based electrolyte for improving LOBs' performances is convenient and significant from both scientific and engineering aspects.

Different from other typical architectures oflithium-ion cells (e.g., NCM//graphite, etc.), Li-metal isindispensable to the construction of Li-O2batteries (LOBs),since Li-metal can be consumed as a lithium source for theinitial discharge process on the cathode side. However, theunstable solid electrolyte interface (SEI)film and relatedhazardous dendrite growth plague the stability and furtherdevelopment of the Li-metal anode, which would beexacerbated by an O2atmosphere in LOBs. Herein, thedithiobiuret (DTB, C2H5N3S2) additive was introduced into atypical ether electrolyte to regulate the Li+solvated sheathconfiguration, and the solvation sheath was tailored and evolvedto a solvent-depleted state. Consequently, an anion-derived SEIfilm architecture with F-rich and O-deficient components wasformed. Systematically, studies of spectroscopy and electrochemical analysis demonstrated that such specific SEI architecturecan trigger grain refinement and promote dendrite-free morphology. Benefiting from the addition of DTB and under an O2atmosphere, the electrochemical performance of both Li/Li symmetrical cells and Li-O2cells has been significantly enhanced.

The reaction mechanism of non-aqueous Li-O-2 batteries is based on the deposition and decomposition of Li2O2. The polarization of Li-O-2 batteries can be rapidly increased by operation under a high rate condition, resulting in the early capacity fade of the cells. Therefore, a well-designed catalyst with a unique structure and excellent catalytic ability is an important way to boost the round-trip performance of Li-O-2 batteries, especially under high current density. In this work, a unique nanoflower structure assembled with Co3O4 nanosheets is synthesized by using 2-methylimidazole (2-MIM) as a structural directing agent. X-ray photoelectron spectroscopy (XPS) and Raman spectra reveal abundant oxygen vacancies on the surface of the Co3O4 nanoflower, which are beneficial for oxygen reduction and evolution reactions and long round-trip lifetime. Density functional theory results demonstrate that Co3O4 catalyst with oxygen vacancies could promote the wetting of Li2O2 on substrate and formation of a Li2O2 nanofilm, thereby boosting the discharge capacity of Li-O-2 batteries. On account of the synergistic effect of abundant oxygen vacancies, the unique structure, and excellent oxygen evolution reaction, Co(3)O(4 )nanoflower-based cells could deliver ultralong lifetime of 276 and 248 cycles with a discharge capacity of 1000 mAh g(-1) under charge/discharge current densities of 0.5 A g(-1) and 1 A g(-1), respectively. This study has shed light on a new strategy for catalyst preparation for long lifetime Li-O-2 batteries.

The increase in charge potential during discharge-charge cycling reduces severely the cycle life of a Li–O2 battery, but its origin has not been fully understood yet. The current study focuses on revealing the intrinsic basis behind the increase of charge potential of a Li–O2 battery and developing a strategy to inhibit this phenomenon. Based on results of X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscope and online electrochemical mass spectroscopy, we find that the performance fading of a Li–O2 battery evidenced by the increase in charge potential is caused by the discharge product transition from Li2O2 to Li2CO3 due to the accumulation of by-product CO2 in cathode side reaction during cycling. We further demonstrate that the performance of a cycled Li–O2 battery can be completely recovered when the accumulated CO2 is evacuated by a vacuum pumping treatment. A strategy is therefore proposed to suppress the CO2 accumulation by preloading a CO2 absorbent agent (CaO) into Li–O2 battery at its assemblage. As a result, the phenomenon of charge potential increase has been effectively inhibited, which improved significantly the cycleability. In comparison with a Li–O2 battery without preloading CaO, the cycling life of the CaO preloaded Li–O2 battery has been prolonged to 148%. This study reveals an important mechanism of performance fading of Li–O2 battery and develops an efficient approach to increase the cycle life, which has thrown new insight into the design and construction of Li–O2 batteries with long lifespan.

By adding a bifunctional plasticizer (SN) and an inorganic conductor (LAGP) to a PEO matrix, an inorganic–organic composite solid-state polymer electrolyte (SPE) was constructed to enhance Li-ion diffusion and interface stability.

Polyhydroquinone–graphene hydrogel composites were prepared via a one-step reaction, and showed high specific capacitance and rate performance as electrode materials for supercapacitors.

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The mechanism of self-discharge (SDC) in active electrolyte enhanced supercapacitors was investigated, and two strategies were devised to suppress the SDC process.

A supercapacitor with enhanced capacitance and energy retention was fabricated using sulfonated polyaniline as the active electrolyte and a semipermeable membrane as the separator.

Water pollution is one of the most pervasive problems afflicting people throughout the world, while adsorption is the most widely used method to remove the contaminants from water. Here, in this paper, we report an eco-friendly graphene oxide-chitosan (GO-CS) hydrogel as a new type of adsorbent for water purification. The GO-CS hydrogels were prepared via self-assembly of GO sheets and CS chains. A three-dimensional network composed of GO sheets crosslinked by CS was found in GO-CS hydrogels. The GO-CS composite hydrogels showed high adsorption capacity towards different contaminants, including cationic and anionic dyes, as well as heavy metal ions. The mechanism of the dye adsorption was investigated with a spectral method, and an electrostatic interaction was found to be the major interaction between ionic dyes and the hydrogel. The influence of the hydrogel composition on the adsorption capacity towards different adsorbates was also studied. Finally, it was demonstrated that the GO-CS hydrogel can be used as column packing, to fabricate a column for water purification by filtration.

Porous composites based on basic aluminum sulfate and graphene hydrogel (BAS@GHG) were prepared via homogeneous precipitation of BAS in GHG, and used as adsorbents for fluoride removal from water. The BAS@GHG composites have a porous structure with a chemically converted graphene three dimensional network coated by a thin layer of amorphous BAS. These composites showed high adsorption capacities of up to 33.4 mg g−1 at equilibrium fluoride concentrations of 10.7 mg L−1 and temperatures of 298 K, higher than those of previously reported graphene and aluminum-based adsorbents. The adsorption kinetics and isotherm were analyzed by fitting experimental data with pseudo-first-order kinetics, the Weber–Morris model and Langmuir equations. The effects of temperature, pH value, and co-existing anions on the adsorption of fluoride were also investigated.

A general method for the fabrication of three-dimensional (3D) porous graphene-based composite materials is reported. This method involves two consecutive electrochemical steps. Firstly, 3D graphene (ERGO) porous material is prepared electrochemically by reducing a concentrated graphene oxide dispersion. Subsequently, the second component is electrochemically deposited onto this 3D ERGO matrix, yielding graphene-based 3D porous composite material. The prepared graphene-based composite materials have a conductive graphene network as the matrix, onto which the second component is homogeneously coated. Conducting polymers, noble metal nanoparticles and metal oxide were successfully incorporated into ERGO architectures, demonstrating the versatility of this method. Taking the ERGO–polyaniline composite as an example, the influence of deposition rate on the morphology of the composite was investigated. Finally, the application of the composite materials prepared with our method was discussed. The high surface area and low electrolyte transport resistance make these electrosynthesized composites suitable electrode materials for electrochemical devices. The ERGO–polyaniline composite electrode showed a high specific capacitance of 716 F g−1 at 0.47 A g−1, and this capacitance could be maintained at 502 F g−1 as the discharge current density was increased up to 4.2 A g−1.