Front cover image: The development of lignin-based photocatalyst has become a cutting-edge strategy towards the high-value H₂O₂ production. However, the enhanced catalytic efficiency and stable environmental adaptability are crucial for the establishment of comprehensive photocatalytic H₂O₂ production system. In article number cey2.666, Xiao et al. propose a new-type lignin-based photocatalyst assisted by graphene oxide and delve into the pathways and mechanisms of the optimized photocatalytic process, providing scientific guidance for the development of a green, low-carbon, and circular economy.

Back cover image: Fuel cells are electrochemical energy conversion devices that promise clean routes of generating energy for enabling carbon neutrality. The electrolyte membrane medium sandwiched between two electrodes plays a vital role in improving their conversion efficiency and the durability. In the article number cey2.677, Liu et al. provide a comprehensive overview on recent advances in nanofiber-based polyelectrolyte membranes for fuel cells. Emerging strategies for the use of electrospun nanofibers and natural nanofibers as proton-exchange membranes and anion-exchange membranes are carefully outlined, respectively. The key challenges and potential solutions in such fields are finally presented.

Recent advances in electrospun nanofibers and natural nanofibers for fuel cell polyelectrolyte membranes are systematically summarized. Both advantages and disadvantages of nanofiber-based polyelectrolyte membranes are also highlighted in improving the performance of fuel cells (PEMFCs and AEMFCs) and practical applications.

A mechanism for GO-assisted photoelectron transition between HOMO and LUMO energy levels in lignin for efficient photocatalytic H2O2 production is proposed. The source of photo-response activity, intensity index, strategies to prolong photoelectron recombination time, energy band optimization, the complete H₂O₂ production process, and the photocatalytic performance evaluation system are elaborated.

The host–guest spatial confinement strategy was developed to synthesize Co₃Fe₇ nanoparticles confined in an N-doped carbon network as bifunctional oxygen electrocatalysts for rechargeable Zn-air battery.

In this work, we describe the construction of a SiO₂@TiO₂ core–shell composite structure through a controlled growth strategy to achieve the precise modulation of the oxygen vacancy (OV) concentration in TiO₂. The abundant Ti–OV–Ti dual sites enable not only efficient adsorption and activation of CO₂ but also a stable adsorption configuration of the *CHO intermediate, thereby contributing to remarkable catalytic activity and selectivity for photoreduction of CO₂ towards CH₄.

Low crystalline Ni-doped molybdenum oxysulfide (Ni–MoO_xS_y) with 2H–MoS₂ structure is synthesized using a hydrothermal procedure. This material shows continuous photocatalytic activity toward CO₂ reduction under LED illumination from UV to IR to produce CO and CH₄ with high conversion rates. Experimental data and theoretical calculations show reaction paths and intermediates of the photocatalytic process.

Pre-intercalation is the mainstream approach to inhibit the structural degradation of Zn-ions migrating in the vanadium oxide cathode of aqueous zinc-ion batteries (AZIBs). This paper reviews the latest advancements in vanadium oxide pre-intercalation for AZIBs and discusses the relationship between the interspace and the electrochemical performance, providing insights into the design of pre-intercalated vanadium oxide cathodes.

Recent breakthroughs in the development of single-atom catalysts for photoelectrocatalytic water splitting are reviewed. The potential design principles and strategies for the future development of SACs in PEC are proposed. In the end, we discuss the challenges and perspectives regarding fundamental research and advances to provide insights and guidelines for this emerging field.

A fully ladder-type, centrosymmetric organic molecule has been designed and engineered, featuring an optimized electronic configuration, extensive electron delocalization, and robust structural integrity. As an electrode material, it provides an exceptional proton-storage capacity of 311.9 mAh g⁻¹, characterized by high stability and an active utilization rate of 89%. This performance is enabled by a significant 8-electron transfer mechanism.

An additive-free, highly printable, viscosity-adjustable, and environmentally friendly MXeneMXene/CNT/CNT hybrid aqueous ink has been successfully developed for 3D printing. The resulting micro-supercapacitors deliver outstanding electrochemical performance and hold great potential for self-powered integrated systems.

A self-recognition separator based on CAU-17 is developed for ion management to achieve highly reversible Zn anodes that selectively repel SO₄^2– ions and H₂O molecules but facilitate Zn²⁺ conduction, leading to reduced side reactions and enhanced transport kinetics.

The synthesis of nickel oxalate nanostructure with tunable operational activity is demonstrated through a streamlined and scalable wet chemistry method. The correlation between dynamic surface reconstruction and catalyst activity was clarified, providing a logical approach for catalyst tuning. The reconstructed catalyst achieved the highest level of performance with high practicality in the ethanol-assisted water splitting and zinc–ethanol–air battery.

Conventional organic ammonium salts possess strong reactivity and penetration capabilities, controlling the formation of surface structures after depositing organic ammonium-based passivators presents a significant challenge. We developed a poly-fluorination strategy for surface treatment in perovskite solar cells, which enabled a high and durable interfacial phase purity after surface passivation, markedly boosting the thermal stability of the devices.