Zinc-ion batteries (ZIBs) have garnered significant interest owing to their intrinsic safety, environmental compatibility, and low cost. However, nonuniform Zn deposition and parasitic side reactions during cycling lead to rapid capacity decay and potential short-circuiting. To address these challenges, we developed a carboxymethyl cellulose–zinc (CMC–Zn) hydrogel electrolyte with self-release capability using a metal–ion crosslinking approach. The dynamically reversible CMC–Zn network continuously supplies active Zn²⁺ during cycling, compensating for electrode consumption in real time. Abundant carboxylate and hydroxyl groups regulate uniform zinc nucleation and growth, while the hydrogen-bonding network synergistically suppresses side reactions, as reflected by a low hydrogen-evolution potential (−0.281 V) and reduced corrosion current density (0.03 mA cm⁻²). With these advantages, Zn||Zn symmetric cells achieve an ultralong lifespan of 6,400 h at 0.5 mA cm⁻², and Zn||Cu half-cells deliver a stable coulombic efficiency of 99.1% over 4,200 cycles. In full-cell testing, self-released Zn²⁺ contributes 29% of the overall capacity, enabling Zn||PANI cells to retain 75% capacity after 2,000 cycles and exhibit a rate-performance recovery of 97.4%. A corresponding flexible ZIB maintains stable operation under various deformation conditions, highlighting the strong potential of CMC–Zn hydrogel electrolytes for next-generation flexible energy-storage devices.

Although aqueous zinc-ion batteries (ZIBs) have demonstrated great potential for large-scale energy storage, the poor chemical stability of Zn metal in aqueous electrolyte leads to irreversible side reactions, restricting widespread utilization of ZIBs. Herein, a hydrophobic-zincophilic bi-functional layer (NLC) derived from paper mill waste lignosulfonate is designed to separate the solid and liquid phases to enhance the performance and stability of zinc anodes in batteries. The abundant C-SO₃H groups in lignosulfonate undergo pyrolysis and in-suit doping into the carbon skeleton to transform into C-S-C bridges, C–S bonds and some C-SO₃H groups during carbonization, which coordinate with Zn²⁺ and reduce the nucleation overpotential of Zn²⁺ to facilitate the de-solvation process and induce uniform deposition. Additionally, the honeycomb hydrophobic carbon skeleton effectively inhibits the corrosion by preventing Zn metal from directly contacting electrolyte and alleviates structural stress during cycling. As a result, the lifespan of symmetrical cells with NLC900@Zn is prolonged to 1000 h at a current density of 1 mA·cm⁻² and 1 mAh·cm⁻². Importantly, the full battery coupled with MnO₂/CNT shows a higher capacity retention of 89.06% after 500 cycles at 0.5 A·g⁻¹, which is higher than that of bare Zn anode (39.76%). This work achieves the combination of waste recycling and zinc ion battery modification, paving a new way for the application of lignin in the field of energy storage.

Molybdenum disulfide (MoS₂) has garnered significant attention as a potential substitute for Pt catalysts in the hydrogen evolution reaction (HER). Furthermore, there is a need to explore cost-effective and efficient electrocatalysts that can perform well across different pH levels. In this study, a straightforward hydrothermal method is presented to synthesize Ni, Co-doped MoS₂ nanosheets on carbon fiber paper (Ni, Co-MoS₂/CFP) for HER in various pH environments. The findings suggest that strategic doping not only alters the structure and composition of Ni, Co-MoS₂/CFP but also enhances its inherent electrocatalytic activity while facilitating the transformation of the MoS₂ phase. The overpotentials observed for Ni, Co-MoS₂/CFP are 95.6, 154, and 144 mV (at 10 mA cm⁻²) under alkaline, acidic, and neutral environments respectively. The exceptional performance of Ni, Co-MoS₂/CFP in HER can be attributed to the introduction of nickel and cobalt dopants which increase porosity and expose more active sites. This one-step doping technique presents a novel approach to modulating catalytic activity across all pH ranges.

A facile way to grow few-layer graphene on high-entropy alloy sheets is presented in this work. We systematically investigate the growth mechanism of graphene using the unique properties of FeCoNiCu_0.25 high-entropy alloys. The intrinsic-trap-regulating growth mechanism derives from the synergistic effect of the multi-metal atoms and sluggish diffusion of high-entropy alloy. As a result, as-obtained few-layer of graphene has the characteristics of wide coverage, large size, good continuity, and high crystallinity with less amorphous carbon and extra wrinkles. Factors such as the Cu content, annealing time, growth temperature, growth time, carbon source flow rate, hydrogen flow rate and heat treatment method play a key role in the growth of high-quality graphene, and the best growth parameters have been explored. Besides, increasing alloy entropy is found to be responsible for the formation of high-quality graphene.

In this paper, porous partially fluorinated graphene (PFG) for supercapacitors (SCs) was fabricated by a mild and secure one-pot hydrothermal method utilizing weakly coordinating anion BF₄⁻ as the fluorine source. The hydrolysis rate of sodium fluoroborate was adjusted by controlling the reaction temperature and PFG containing semi-ionic C-F bonds was obtained, where the content of semi-ionic C-F bonds in PFG can be easily regulated. The final experimental results show that the incorporation of fluorine not only modulates the electrochemical properties of the material, but also creates abundant pores. When assembled in a symmetric supercapacitor, the PFG shows a high specific capacitance of 269.7 F g⁻¹ at 1 A g⁻¹ and a superior rate capability with 89.3% capacitance retained, as the current density is increased from 1 A g⁻¹ even to 20 A g⁻¹. Furthermore, the resultant energy density for PFG is 9.4 Wh kg⁻¹ at a power density of 250.0 W kg⁻¹ (1 A g⁻¹). All these results confirm that as-prepared partially fluorinated graphene is appropriate for the application in SCs and mass production.