Kefeng Xie

Conventional thermocatalytic acetylene hydrogenation relies on elevated-pressure environments, often resulting in excessive energy expenditures and suboptimal ethylene yields. In contrast, room-temperature electrocatalytic acetylene semihydrogenation (EASH) offers a sustainable route for ethylene purification. However, its industrial implementation is impeded by inadequate ethylene selectivity and concurrent hydrogen evolution reactions. In this study, Ni-based single-atom catalysts anchored on the armchair and zigzag edges of graphene nanoribbons were designed, and density functional theory computations demonstrate that edge effects can modulate the electrocatalytic ethylene selectivity of NiN4 single-atom catalysts. First, the calculated binding energy, cohesive energy, formation energy, and dissolution potential indicate that all NiN4-AC-edge and NiN4-ZZ-edge configurations exhibit excellent structural stability. Second, Gibbs free energy analysis of the reaction pathways demonstrates that the 1-NiN4-AC-edge and 2-NiN4-ZZ-edge catalysts can significantly promote the EASH reaction while inhibiting the hydrogen evolution side reaction. Lastly, electronic property computations indicate that the d-band center of the active Ni site, alongside the binding strength of ethylene, function as reliable descriptors to forecast EASH selectivity. The coupling effect between the Ni d-orbital and the C2H4p-orbital in the 1-NiN4-AC-edge and 2-NiN4-ZZ-edge configurations plays a crucial regulatory role during the ethylene desorption process. The results of this research offer theoretical support for the rapid development of highly efficient EASH catalysts and are expected to advance the industrialization of this technology.

Rational design of interfacial electronic structures and defect sites is pivotal for advancing chemiresistive gas sensing, yet achieving synergistic modulation remains a formidable challenge. Herein, we report a ternary Pd–HPW–ZnO heterostructure constructed via the integration of phosphotungstic acid (HPW) clusters and Pd nanoparticles onto porous ZnO nanosheets. This unique architecture establishes a robust electronic coupling network, where HPW acts as an electron sink, inducing electron depletion in both ZnO and Pd species to form electron-deficient Pd sites. This electronic modulation, corroborated by XPS and DFT calculations, significantly optimizes the Pd d-band center and enhances the surface Lewis acidity. Furthermore, the synergistic interaction triggers a substantial enrichment of oxygen vacancies and facilitates the spillover of active oxygen species. Consequently, the optimized sensor exhibits an extraordinary response of 2016.70 to 50 ppm triethylamine (TEA) at a low operating temperature of 110 °C, surpassing pristine ZnO by nearly 60-fold. The sensor also demonstrates ultrafast response/recovery kinetics (16/150 s), excellent selectivity against interfering volatiles, and robust long-term stability. This work provides a paradigm for boosting sensing performance through precise interfacial electronic regulation and defect engineering in multicomponent heterostructures.

Hydrogel electrolytes are pivotal for flexible zinc-ion batteries (ZIBs) yet suffer from an intrinsic trade-off between mechanical robustness and ionic conductivity. Herein, drawing inspiration from the “adhesion-conduction” architecture of spider webs, we developed a hierarchical hydrogel electrolyte (MTP) by incorporating tannic acid (TA)-modified MXene nanosheets (MT) into a polyacrylamide (PAM) skeleton to construct uniform 3D ion-conductive pathways. This bioinspired hierarchy serves a dual function: The PAM framework ensures mechanical integrity, while the MT network creates directed low-resistance channels for Zn ²⁺ transport. Specifically, the dense array of polar groups on MXene and phenolic hydroxyls on TA act as “sticky sites”, which accelerate desolvation kinetics and homogenize Zn ²⁺ flux. Consequently, the MTP electrolyte achieves an impressive ionic conductivity of 27.69 mS cm ⁻¹ and a high Zn ²⁺ transference number of 0.833. Enabled by this design, Zn//Zn symmetric cells demonstrate an ultralong lifespan of 4600 h (> 6 months) at 0.5 mA cm ⁻² /0.5 mAh cm ⁻² . Furthermore, Zn//Z-VO full cells exhibit outstanding cyclability, retaining 74.5% capacity after 2000 cycles at 2 A g ⁻¹ and maintaining durable operation for over 10,000 cycles at 5 A g ⁻¹ . This work successfully translates a biological blueprint into a practical strategy for resolving the kinetic and stability challenges in high-performance flexible ZIBs.

Inspired by the efficient mass transport and interfacial exchange of natural vascular bundles, this study presents a bioinspired rod‐in‐hollow‐tube architecture, MoO ₃ @NiMoO ₄ ‐TH, engineered via precise kinetic control of the Kirkendall effect. This unique structure features a highly ordered, high‐curvature linear heterointerface between the MoO ₃ core and NiMoO ₄ shell, which significantly enhances charge transfer and reaction dynamics. The optimized heterostructure demonstrates exceptional triethylamine (TEA) sensing performance, achieving a remarkable response (R _a /R _g = 513.5 ± 3.8, n = 3 at 50 ppm TEA and 210°C) and ultrafast response/recovery times (7 s/51 s) with linear detection ranges from 0.5 to 200 ppm TEA and a low detection limit of 137 ppb. In situ spectroscopic analysis and finite element simulations reveal that the well‐defined heterointerface promotes directional electron migration, enriches reactant concentration via confinement effects, and facilitates efficient activation of oxygen species. Compared to randomly distributed heterostructures, the rod‐in‐hollow‐tube configuration exhibits high surface energy and accelerated charge separation, thereby optimizing adsorption and oxidation kinetics. Practical application in monitoring fish freshness further underscores the reliability of sensors. This work establishes a generalized strategy for designing biomimetic nanomaterials with tailored interfaces, advancing high‐performance sensors for real‐time environmental monitoring and food safety.

In a correspondence related to our previous publication in Angewandte Chemie , Bianchi, Melguizo, et al. (B.M.) commented on the mechanistic interpretation and experimental framework underlying the interaction between 3,6‐bis(2‐morpholinoethyl)‐1,2,4,5‐tetrazine (BMT) and I ₃ ⁻ in Zn‐I ₂ batteries. In this reply, we show that the central findings and mechanistic interpretation of our work remain valid. First, B.M. should recognize the fundamental distinction between bulk solution chemistry and the reactions occurring at the electrochemical interface. It is critical to acknowledge that chemical reactions involving identical reactants may proceed through entirely different pathways under different physicochemical conditions—a principle that is particularly significant for electrochemistry. In Zn‐I ₂ batteries, the cathodic electrochemical double layers (EDLs) constitute a highly polarized, spatially confined, and locally alkaline microenvironment. The 1:1 first‐step association constant reflects the rapid complexation kinetics of nonprotonated BMT toward I ₃ ⁻ , highlighting its effectiveness in anchoring triiodide species at the cathode. Importantly, this value does not imply exclusive 1:1 complex formation, and it remains fully consistent with the 1:2 coordination stoichiometry revealed by the Job's plot analysis. Furthermore, well‐converged density functional theory calculations results are fully consistent with various experimental evidence, including in situ spectroscopic, in situ electrochemical measurements, and UV‐vis titration experiments in chloroform. Accordingly, the nonprotonated BMT‐I ₃ ⁻ coordination mechanism proposed for Zn‐I ₂ batteries is robust and internally consistent. In contrast, the protonated BMT‐I ₃ ⁻ coordination studies reported by B.M. suffer from serious scientific/technical flaws, owing to interference from competing anions and the use of ill‐defined, strongly acidic solutions. Such experimental environments are fundamentally different from the cathodic EDL in Zn‐I ₂ batteries. Nevertheless, to appropriately acknowledge prior contributions, multiple studies by B.M. are cited in both the Introduction and the Supporting Information. These citations fully comply with academic standards. This reply therefore clarifies the BMT‐I ₃ ⁻ coordination mechanism in electrochemistry, reaffirms the validity of our conclusions, and underscores the decisive role of the EDL microenvironment in governing cathodic reactions.

In a correspondence related to our previous publication in Angewandte Chemie , Bianchi, Melguizo, et al. (B.M.) commented on the mechanistic interpretation and experimental framework underlying the interaction between 3,6‐bis(2‐morpholinoethyl)‐1,2,4,5‐tetrazine (BMT) and I ₃ ⁻ in Zn‐I ₂ batteries. In this reply, we show that the central findings and mechanistic interpretation of our work remain valid. First, B.M. should recognize the fundamental distinction between bulk solution chemistry and the reactions occurring at the electrochemical interface. It is critical to acknowledge that chemical reactions involving identical reactants may proceed through entirely different pathways under different physicochemical conditions—a principle that is particularly significant for electrochemistry. In Zn‐I ₂ batteries, the cathodic electrochemical double layers (EDLs) constitute a highly polarized, spatially confined, and locally alkaline microenvironment. The 1:1 first‐step association constant reflects the rapid complexation kinetics of nonprotonated BMT toward I ₃ ⁻ , highlighting its effectiveness in anchoring triiodide species at the cathode. Importantly, this value does not imply exclusive 1:1 complex formation, and it remains fully consistent with the 1:2 coordination stoichiometry revealed by the Job's plot analysis. Furthermore, well‐converged density functional theory calculations results are fully consistent with various experimental evidence, including in situ spectroscopic, in situ electrochemical measurements, and UV‐vis titration experiments in chloroform. Accordingly, the nonprotonated BMT‐I ₃ ⁻ coordination mechanism proposed for Zn‐I ₂ batteries is robust and internally consistent. In contrast, the protonated BMT‐I ₃ ⁻ coordination studies reported by B.M. suffer from serious scientific/technical flaws, owing to interference from competing anions and the use of ill‐defined, strongly acidic solutions. Such experimental environments are fundamentally different from the cathodic EDL in Zn‐I ₂ batteries. Nevertheless, to appropriately acknowledge prior contributions, multiple studies by B.M. are cited in both the Introduction and the Supporting Information. These citations fully comply with academic standards. This reply therefore clarifies the BMT‐I ₃ ⁻ coordination mechanism in electrochemistry, reaffirms the validity of our conclusions, and underscores the decisive role of the EDL microenvironment in governing cathodic reactions.

Aniline (PhNH ₂ ) is usually prepared via the hydrogenation of nitrobenzene (PhNO ₂ ) under high-temperature and high-pressure conditions.