Front cover image: The traditional reliance on expensive noble metal-based electrocatalysts for water splitting reactions, such as the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), has stimulated researchers to innovate and develop novel electrocatalytic systems that are both cost-effective and efficient. In the article number cey2459, Zhou and co-workers reported a new multicomponent nanocomposite MW/HK/NiMn-S, features a unique architecture, high porosity, numerous electroactive Cu/Ni/Mn sites, fast charge transfer, excellent structural stability, and conductivity. It is significantly superior to standard noble metal-based Pt/C and IrO₂ systems. The enhanced electrocatalytic performance of the nanocomposite can be attributed to the synergistic interplay among its diverse components. The distinctive characteristics exhibited by each element within this multi-component composite offer intriguing possibilities for exploration in the field of water splitting.

Back cover image: Mixed-halide perovskite is necessary for successful application of tandem solar cells. However, it suffers from serious phase segregation owing to the presence of residual strain, which induces structural disorders, in article number cey2.387, Duan et al. report an elastic interface to release lattice strain of mixed-halide inorganic perovskite film by using a stretchable alkenamides terminated Ti3C2Tx MXene as additive, universally healing the defective lattice and improving the efficiency and stability of wide-bandgap perovskite solar cell owing to the suppressed phase segregation.

A new multiwalled carbon nanotubes/Cu-metal–organic framework/sulfidized-NiMn-layered double hydroxide (MW/HK/NiMn-S) nanocomposite was assembled, characterized, and applied as an exceptionally powerful dual-function electrocatalyst for the H₂ and O₂ evolution processes. The developed multi-interface engineering approach provides new perspectives for designing future dual-function electrocatalysts based on tri- or multimetallic composites with ideal conductivity, stability, and advanced water-splitting performance.

An elastic interface is fabricated to release residual lattice compressive and tensile strain of mixed-halide inorganic CsPbIB₂ perovskite film by using a stretchable alkenamides terminated Ti₃C₂T_x MXene as an additive, universally healing the defective lattices to suppress the nonradiative recombination and improving the efficiency and stability of wide-bandgap perovskite solar cells.

This review aims to give insightful direction and a fresh motivation toward the electrochemical synthesis of ammonia via nitrogen reduction reaction (ENRR). We proposed emerging electrocatalysts toward ENRR such as single-atom catalysts, MXenes, and metal–organic frameworks for the synthesis of green ammonia.

Inspired by wood, we have developed an effective approach to engineer a hierarchical nanocomposite via self-assembly of calcium silicate hydrate and polyvinyl alcohol polymer chains. The versatile protective material demonstrates an unprecedented combination of light weight (0.018 g cm⁻³), high stiffness (204 MPa), negative Poisson's ratio (−0.15), remarkable energy dissipation (6.67 × 10⁵ J m⁻³), superior thermal insulation (0.0204 W m⁻¹ K⁻¹), and excellent fire retardancy (UL94-V0).

The porous/dense/porous trilayered Na₅YSi₄O₁₂ is used in an all-solid-state sodium/sulfur battery as a scaffold for the electrode active materials. The dense middle layer separates both electrodes and prevents sulfur shuttling and sodium dendrite growth. The porous layers on both sides accommodate the active materials and mitigate volume changes, thus increasing the contact area and distributing the local current.

A sandwich-structure hybrid of hollow β-Mo₂C nanotubes and N-doped carbon nanosheets is smartly designed and scalably fabricated using a binary molten salt involved methodology for efficient hydrogen evolution reaction as a competitive electrocatalyst.

A poly(propylene glycol) (PPG)-based aqueous electrolyte is designed for Li⁺/Zn²⁺ hybrid ion batteries. PPG in the electrolyte can not only enhance the hydrogen bonding in water but also tailor the solvation sheath of Zn²⁺ to weaken Zn−H₂O interactions; the decomposition of TFSI⁻ contributes a ZnF₂-enriched solid electrolyte interface at Zn anode to further prevent water decomposition and restrain Zn dendrites.

We introduce hierarchically micro/nano-wrinkled elastomeric energy storage electrodes with various form factors using metal nanoparticle assembly-assisted electrodeposition of Ni and NiCo layered double hydroxides. Based on this unique approach, the hierarchically structured elastomeric electrodes with favorable interfacial interactions between electrode components show a large active surface area, good mechanical properties, and unprecedentedly high energy storage performance.

Transition-metal metaphosphates (TMMPs) have a three-dimensional open-framework structure and a high content of P (which exists as PO₃⁻), and therefore have been recognized as highly efficient catalysts for oxygen evolution reaction, the bottleneck of electrochemical water splitting. Furthermore, TMMPs can also contribute to hydrogen evolution reaction in alkaline and neutral media by facilitating water dissociation, and thus, overall water splitting can be achieved using this kind of material.

PdPt bimetallenes (PdPt BMLs) are synthesized by a galvanic replacement reaction, which leads to enhancement of intrinsic electroactivity for both the formate oxidation reaction and the hydrogen evolution reaction with respect to Pd metallence due to the synergistic effect. Also, the PdPt BMLs||PdPt BMLs formate electrolyzer requires an operational voltage of only 0.31 V for H₂ production, which is 1.48 V lower than that of the traditional water electrolysis system.

Herein, carbon encapsulated CoNi coupled with CoNiMoO for urea-assisted water electrolysis at large current density is theoretically and experimentally studied. Theoretical calculations reveal that the electronic is redistributed at the heterogeneous junction interface between CoNi and N-doped-carbon, which optimizes the adsorption/desorption energies for urea/hydrogen reaction intermediates; thus, it obtains good hydrogen evolution reaction and urea oxidation reaction activity.

A MoS₂ catalyst is uniformly deposited on carbon paper using the atomic layer deposition process. The MoS₂-based heterostructure anode for iodide oxidation reaction (IOR) combined with a Pt@C cathode for hydrogen evolution reaction delivers 10 mA cm⁻² at a low cell voltage of 0.66 V. By connecting this electrolyzer with a single perovskite photovoltaic cell, the resulting photovoltaic–electrochemical device coupled with IOR produces a record-high current density of 21 mA cm⁻² without external bias.

Defect engineering of ternary Cu–In–Se quantum dots is achieved by regulating Lewis acid–base reactions between metal halide–oleylamine complexes and selenium precursors. Optical and electrical properties such as carrier concentrations, mobilities, and lifetimes are tuneable by the density of Cu vacancies. Photoanodes with defect-engineered quantum dots show outstanding photoelectrochemical hydrogen generation with excellent photocurrent density (10.7 mA cm⁻² at 0.6 V_RHE).

Gradient layer-coated diamond particles were prepared by combining magnetron sputtering and heat treatment. An ultra-light and high-thermal-conductivity diamond–copper composite was prepared using high-temperature and high-pressure technology. A coherent interface exists between copper and gradient layer-coated diamond, which effectively improves the electron–phonon coupling thermal transport efficiency between the interfaces.

We report a controllable and large-area growth strategy based on sonochemistry for the fabrication of single-crystalline ZnO nanosheets under ambient conditions as a superb Zn anode with a very low polarization overpotential down to ~20 mV. The developed Zn@SC-ZnO//MnO₂ aqueous Zn-ion batteries delivers a voltage efficiency of 88.2% under a current density of 500 mA g⁻¹ at the stage of 50% depth of discharge.