Xuebin Lu

Iron single‐atom catalysts (Fe SACs) offer excellent performance for the oxygen reduction reaction (ORR). However, their catalytic activity remains limited by the coordination structure and the accessibility of the active sites. Optimizing the local coordination and pore structure of the catalyst is imperative. Herein, we report a dual‐template strategy using oxygen‐rich lignin to synthesize Fe single‐atom catalysts with asymmetric Fe‐N ₃ O coordination embedded in hierarchical porous carbon (HPC). Lignin serves both as the carbon precursor and a coordination modulator, while Zn/MgO dual templates facilitate the creation of a tri‐modal (micro/meso/macro) pore architecture. Operando spectroscopy and DFT calculations reveal that the asymmetric Fe‐N ₃ O configuration downshifts the d‐band center of Fe, which weakens *OOH adsorption and accelerates charge transfer, leading to enhanced intrinsic activity. The optimized Fe‐N ₃ O@HPC catalyst exhibits exceptional ORR activity in 0.1 M KOH, with a half‐wave potential of 0.87 V vs. RHE, surpassing Pt/C by 40 mV. Moreover, it exhibits significantly smaller decay over 30 h than commercial Pt/C. In zinc‐air batteries, the catalyst delivers a peak power density of 174.2 mW cm ⁻² and a specific capacity of 807 mAh g _Zn ⁻¹ . This research offers a cost‐effective methodology to design and fabricate high‐performance catalysts for ORR.

Nitrogen‐containing chemicals are indispensable to modern society, among which lactams occupy a central position owing to their extensive use as polymer precursors, high‐performance solvents, and pharmaceutical building blocks. Conventional petroleum‐based production routes, however, are increasingly constrained by environmental and resource concerns, underscoring the urgency of developing sustainable alternatives from renewable biomass. Despite growing research activity, existing reviews on biomass‐derived lactam synthesis remain fragmented, typically concentrating on a limited number of established pathways and lacking a systematic mapping of renewable feedstocks, reaction networks, and catalytic strategies. To bridge these gaps, this review provides a systematic overview of representative biomass‐based lactams, with emphasis on γ‐, δ‐, and ε‐lactams, by correlating diverse renewable feedstocks with their corresponding synthetic routes under heterogeneous catalysis. This work aims to establish a coherent framework for biomass valorization and to offer conceptual and practical guidance for advancing efficient, selective, and sustainable lactam synthesis.

High intake tower structures exhibit significant time-varying characteristics in their seismic performance during service life due to environmental erosion and material deterioration. This paper establishes a time-varying seismic fragility analysis framework for intake towers over their full life cycle based on the incremental dynamic analysis (IDA) method. By introducing time parameters, time-varying probabilistic seismic demand models based on displacement and local damage indices are constructed, and five performance levels are defined. The research results indicate that with increasing service life, the probability of the structure reaching critical performance levels exhibits a nonlinear growth. After 40 years of service, material strength and elastic modulus begin to decline significantly, with evident degradation of seismic performance. At a seismic acceleration of 0.8 g, the probability of the 60-year-service structure reaching the slight damage limit state (LS₁) has reached 99%, while the probability of reaching the collapse limit state (LS₄) exceeds 25%. The local damage index results demonstrate that under the same seismic intensity, the exceedance probability of tower-side damage exceeding LS₁ for the 60-year-service structure has increased by approximately 10% compared to that of the new structure (0-year service). Therefore, in the seismic design and retrofitting decision-making for intake towers, the time-varying characteristics over the entire service life must be fully considered. Particularly when the service life exceeds 40 years, seismic fortification standards should be appropriately enhanced or targeted strengthening strategies should be developed based on time-dependent fragility curves, so as to avoid underestimating long-term seismic risks. This study provides a quantifiable scientific basis for whole-life safety assessment and resilience enhancement of high-rise intake towers.

Gamma‐Valerolactone (GVL) has emerged as a promising biomass‐derived solvent for the catalytic conversion of sugars into furan chemicals such as 5‐hydroxymethylfurfural and furfural. Although GVL‐based solvent systems have demonstrated superior performance, the mechanistic roles of GVL are often described qualitatively and remain insufficiently clarified. This review systematically synthesizes recent advances and organizes insights from the literature to elucidate the roles of GVL in sugar‐to‐furan conversion. The effects of GVL‐based solvents are summarized into several interconnected aspects, including enhanced substrate solubility, regulation of reaction pathway selectivity, stabilization of key transition states, mediation of reactant enrichment, and facilitation of product separation. These insights highlight GVL as a multifunctional reaction medium rather than an inert solvent and provide guidance for the rational design of solvent systems for efficient biomass valorization.

Shifting from conventional thermodynamic descriptors toward charge transport dynamics regulation has emerged as an innovative-catalyst-design methodology. A general strategy is developed for synthesizing Sv-chalcogenide/Ti₃C₂ photocatalytic architectures (Sv represents sulfur vacancies; chalcogenides include Zn_0.5Cd_0.5S, ZnIn₂S₄, CdIn₂S₄, CdS) featuring core–shell dual-tunable parameters via metal–organic frameworks-templated topotactic transformation and defect-mediated heterocomponent anchorage. These nanoreactors leverage controlled charge transport behavior, encompassing charge transport dimensionality and charge transport pathway, to manipulate specific molecular catalytic behavior, dictating polyethylene terephthalate (PET) photoreforming pathway bifurcation between dehydrogenation (glyoxylic acid, CHOCOOH) and hydrodeoxygenation (acetic acid, CH₃COOH). Specifically, the Zn_0.5Cd_0.5S topotactic lattice transformation regulates charge transport dimensionality to control the catalyst-substrate interaction/distortion energy, thereby enabling electronic-configuration-dependent adsorption and selective activation of key intermediates for divergent product generation. The Zn_0.5Cd_0.5S/Ti₃C₂ interfacial built-in electric field (BIEF) establishment creates directional charge transport pathways that induce photocarrier localization/delocalization, resulting in robust productivity feedback. These adjustable-configuration catalysts achieve dehydrogenation-dominated CHOCOOH (81% selectivity, 2.63 mmol·g^–1·h^–1) on Sv-Zn_0.5Cd_0.5S-thin/Ti₃C₂ and hydrodeoxygenation-driven CH₃COOH (86% selectivity, 1.53 mmol·g^–1·h^–1) on Sv-Zn_0.5Cd_0.5S-bulk/Ti₃C₂ during PET conversion. This work establishes a pioneering paradigm for geometrical transformation-charge transport dimensionality-reaction pathway switching and interfacial engineering-charge transport pathway-catalytic activity improvement, elucidating the substantial impact of charge transport behavior on specific molecular catalytic behavior.

C─H bond activation represents a ubiquitous transformation in chemistry, yet challenging owing to the complex requirements for proton and electron transfer. A general strategy for constructing proton–electron dual‐transport‐channel photocatalysts: hollow hierarchical Co ₃ S ₄ /Sv‐chalcogenide/Ti ₃ C ₂ nanoreactors (Sv = sulfur vacancies, chalcogenide = CdIn ₂ S ₄ , ZnIn ₂ S ₄ , CdS) is developed via lateral epitaxy and defect‐mediated heterocomponent anchorage. These ternary‐component nanoreactors integrate dynamic hydrogen‐bonding nanonetworks and asymmetric dual‐interface built‐in electric fields (BIEFs), acting as the strong proton/electron extractors for steering proton‐coupled electron transfer (PCET) in C─H activation of biomass‐derived molecules. The BIEFs‐induced electron transport channel is featured by powerful photocarrier enrichment and feeble photocarrier recombination at Co ₃ S ₄ /chalcogenide S‐scheme heterointerface, and photocarrier localization and delocalized‐electron transport at Sv‐chalcogenide/Ti ₃ C ₂ Schottky heterointerface. The hydrogen bond network‐induced proton transport channel lies in electron‐enriched interfacial lattice oxygen for mediating the substrate deprotonation via nucleophilic abstraction, and the hydrophilic MXene for guiding proton transfer along modified dynamic hydrogen‐bonding nanonetworks. By virtue of dynamically optimized molecular catalytic behavior accomplished by pivotal intermediate adsorption/activation regulation, representative Co ₃ S ₄ /Sv‐CdIn ₂ S ₄ /Ti ₃ C ₂ HNR exhibits remarkable C─H activation performance and broad substrate compatibility. This work establishes a pioneering paradigm for manipulating proton–electron dual‐transport‐channel by hydrogen‐bonding nanonetworks and BIEFs, offering novel strategies for regulating molecular catalytic behavior in complex reaction pathways.

A template-assisted approach was employed to synthesize a MOF-on-MOF derived catalyst for the selective oxidation of 5-hydroxymethylfurfural (5-HMF) to produce 2,5-furandicarboxylic acid (FDCA). Characterization revealed that the catalyst forms a cobalt–manganese metal oxide composite phase with a hierarchical porous structure and uniformly distributed Co/Mn active sites. The oxygen vacancies work together with the Lewis acid sites to gradually oxidize the hydroxyl and aldehyde groups in 5-HMF. In the context of reaction conditions that have been identified as optimal (140 °C, 6 h, 50 mg catalyst, 5.88 mol L⁻¹ H₂O₂), the yield of FDCA was 87.55%, accompanied by 5-HMF conversion rate of 98.66%. The catalyst exhibited exceptional cycling stability, sustaining an FDCA yield exceeding 75% across five cycles. Mechanism studies indicate that the Co–Mn bimetallic synergistic effect optimizes the reaction pathway through electron transfer and oxygen species activation, while the microporous structure prolongs the residence time of intermediates through confinement effect, promoting multi-step oxidation. Compared with the single-metal MOFs derived catalysts, this catalyst has significantly improved adsorption performance and oxidation efficiency, providing an efficient solution for the green synthesis of the bio-based polyester monomer FDCA.

Defect engineering combined with thermal activation enhances dual-origin Brønsted acidity in UiO-66, enabling superior fructose dehydration to HMF and offering a tunable strategy for efficient biomass conversion.