Aug 2026· Angewandte Chemie· pp.
e1230832
· 0 citations· 47 references
Medicine
Abstract
Dodecahydro-N-ethylcarbazole (12H-NEC) is a promising liquid organic hydrogen carrier (LOHC), yet its practical application is still constrained by slow dehydrogenation kinetics and extreme reliance on external heating even over most effective Pd-based catalysts. Here we identify that the hydrogen removal step with a high barrier is the precise kinetic bottleneck of 12H-NEC dehydrogenation, which remains underexplored. To effectively overcome this limitation, we report a light-activated dual-site hydrogen removal pathway using Pd nanoparticles supported on defective N-doped TiO2. Under irradiation, charge transfer from the support to Pd weakens Pd-H interactions, while accumulated holes on the support promote hydrogen spillover to Ti defect sites, generating weakened Ti-H species alongside Pd-H. This thereby initiates a new hydrogen formation dual-site pathway by combining Pd-H and Ti-H with an overall dehydrogenation barrier of 0.46 eV only, 0.74 eV lower than the conventional thermal Pd-localized pathway, resulting in a 42-fold higher H2 release rate relative to dark conditions at 140°C. Even under concentrated natural sunlight without external heating, near-complete dehydrogenation with a capacity of 5.65 wt.% H2 within 1 h is achieved from 12H-NEC. This work charts a promising course for practical hydrogen storage applications of LOHCs without secondary energy input.
Electrochemical hydrodehalogenation (ECHD) offers a green route to remove refractory haloacetic acids (HAAs), yet conventional catalysts often fail to achieve effective dehalogenation, producing more toxic partially dehalogenated intermediates. Here, we report a synergistic ECHD process of Cu-O capture, Pd-X activation, and H* utilization on uniform bipolar sites Pdδ--Cuδ+ that enable efficient ECHD of HAAs. These bipolar sites, with a defined coordination environment and a precise 1:1 Pd:Cu atomic ratio, are periodically embedded within a three-layer ordered intermetallic single-atom alloy shell grown on a cubic Cu core. The well-defined motif provides an ideal platform for elucidating the structure-function relationship. Theory and experimental data reveal that the bipolar sites downshift the Pd d-band center, enhance Pd binding energy, and reduce the water-dissociation barrier relative to Cu and Pd nanocubes, thereby optimally balancing the kinetics and thermodynamics of dehalogenation and hydrogenation while mitigating Pd deactivation. The facilitated H* generation over these bipolar sites increases the availability of reactive H* species and markedly promotes effective ECHD. Consequently, Cu/B2 Pd1Cu exhibits the highest trichloroacetic acid (TCAA) degradation rate, acetic acid formation, and overall dechlorination ratio compared with Cu and Pd nanocubes. The TCAA degradation rate constant on Cu/B2 Pd1Cu is nearly twice that of Cu and Pd nanocubes, and the acetic acid yield (0.78 mg L-1) is 1.55 and 3.71 times higher, respectively. This study establishes ordered Pd1Cu intermetallic single-atom alloy layers with uniform bipolar sites as an effective platform for efficient ECHD of HAAs and provides a general design strategy for multifunctional electrocatalysts that couple substrate activation with efficient H* utilization.
Juening Fan, Yang Liu, Runze Si et al.· Journal of Hazardous Materia...· 0 citations
Liquid organic hydrogen carriers are promising for large-scale and long-distance hydrogen storage and transportation. Considering that renewable hydrogen sources are often decentralized and intermittent, designing a catalyst that is simultaneously cost-effective, room-temperature compatible, and environmentally-friendly remains a significant challenge. This contribution introduce a single Pd
1
assisted fully exposed Ru clusters supported on defective graphene/nanodiamonds hybrid support (Ru
n
Pd
1
/ND@G) catalyzing efficient toluene hydrogenation under solvent-free conditions, in which the conversion of toluene could achieve 100% even at room temperature. Remarkably, Ru
n
Pd
1
fully-exposed cluster delivers an exceptionally high turnover frequency of 35199.5 h
−1
at the absence of solvent, which is 5.9 times higher than that of the monometallic Ru/ND@G catalyst. The catalyst exhibits maximized atomic efficiency, excellent recyclability and reaction scalability. Combing with theoretical calculations, it is revealed that Pd
1
assisted fully-exposed Ru cluster catalysts promoted H
2
activation and C-H formation as well as improved reactant (product) adsorption (desorption), which all contribute to the superior activity of Ru
n
Pd
1
fully-exposed clusters. This work offers a practical strategy for efficient hydrogen energy utilization under solvent-free conditions.
Fenton reaction has been widely applied in wastewater treatment, however, the homolytic cleavage of hydrogen peroxide (H2O2) toward selective formation of hydroxyl radical (•OH) remains a key challenge. In this study, the FeOF catalyst was synthesised by introducing highly electronegative fluorine atoms to modulate the coordination environment of iron sites. The resulting O-Fe-F configuration significantly enhances surface hydrolytic hydroxylation, increasing the density of dual sites by 158% and achieving a breakthrough with 4.6-fold enhancement in •OH production. The generation of dual sites shifts the Fe d-band center upward toward the Fermi level (FeOCl: -3.403 → -3.014 eV; FeOF: -3.350 → -3.126 eV), reduces the rate-limiting energy barrier (FeOCl: 0.13 → -0.56 eV; FeOF: 0.11 → -0.88 eV), and the sites act as a bridge between FeOF and H2O2 to facilitate electron transport. Moreover, the FeOF-loaded in hollow fiber membrane demonstrates efficient pollutant removal and robust long-term stability in continuous operation of real water matrices with a flux up to 398 L m-2 h-1. This work offers a new theoretical framework for the design of efficient Fenton-like catalysts.
Dual-atom catalysts (DACs) hold significant promise for advanced oxidation processes. However, their practical applications are often limited by sluggish electron transfer and low atomic utilization efficiency. Herein, we report that P-bridged Fe-Cu dual-atom catalysts (FeCu-NP-C) are precisely modulated by first-shell N and P ligands, forming a unique N3Fe-P1-CuN3 structure. The Fe-P-Cu bridging bond induces d-p-d gradient orbital coupling to establish a directional electron-transfer channel from the Cu site (electron donor) to the Fe site (electron acceptor) for enabling ultrafast pollutant degradation and bacterial inactivation. The FeCu-NP-C catalyst enables peroxymonosulfate activation to selectively generate high-valent iron-oxo species with a steady-state concentration of 5.80 × 10−5 mM, which is 100 times higher than that of Fe-NP-C. The FeCu-NP-C membrane reactor achieves a treatment capacity of 500 L of wastewater per gram of catalyst over 100 h, at an operational cost of USD 0.16 per tonne. This work provides deep insights into the bridge-mediated orbital interactions of DACs for water decontamination. P-bridged Fe-Cu dual-atom catalysts with N3Fe-P1-CuN3 structure enable directional electron transfer via d-p-d orbital coupling for efficient peroxymonosulfate activation. The FeCu-NP-C reactors achieve high-efficiency performance and long-term stability.
Ke Zhu, Yuheng Yao, Yongjian Zeng et al.· Nature Communications· 1 citation
Liquid organic hydrogen carriers (LOHCs) based on cycloalkane/aromatic pairs are promising for safe hydrogen storage and transportation, but their practical implementation is limited by sluggish dehydrogenation kinetics and catalyst deactivation under working conditions. Herein, we report a rationally designed platinum catalyst supported on curved graphene-coated nanodiamond (ND@G), in which fully exposed subnanometric Pt clusters (Ptn) and three-dimensional Pt clusters (Ptc) are integrated in close proximity on the support (Ptn+c/ND@G), which delivers remarkably enhanced hydrogen production in the solvent-free dehydrogenation of bicyclohexyl and other representative cycloalkanes, outperforming either single-counterpart catalysts or their physical mixtures while maintaining good recyclability. Mechanistic investigations combined with density functional theory calculations demonstrate that this synergistic effect originates from the cooperation between these respective Pt ensembles: Ptc sites possess higher intrinsic activity for C-H bond activation than Ptn clusters, yet are more susceptible to poisoning. By contrast, Ptn clusters, although less active for substrate activation, remain operative in the presence of aromatic adsorbates. Hydrogen generated on Ptn clusters can weaken product binding on adjacent Ptc sites via support-mediated spillover. As a result, poisoning is mitigated, active Ptc sites are continuously regenerated, and overall dehydrogenation performance is enhanced. These findings provide a general design principle for developing high-performance LOHC dehydrogenation catalysts through Pt ensemble engineering and support-mediated hydrogen management.
Chengyu Li, Yong Wang, Zezheng Hao et al.· Journal of the American Chem...· 0 citations
Covalent organic frameworks (COFs) have attracted considerable attention as promising photocatalysts for hydrogen peroxide (H2O2) production. To further improve their catalytic performance, a quaternary ammonium functionality was introduced into the bipyridine units of the COF via a post-synthetic modification strategy. Under identical irradiation conditions, the cationized Pry-COF-QA achieved a H2O2 production rate of 7.31 mmol·h–1·g–1, which is markedly higher than that of the non-protonated Pry-COF (5.50 mmol·h–1·g–1). To gain mechanistic insight into the enhanced activity, density functional theory (DFT) calculations were performed. The results indicate that the incorporation of the quaternary ammonium group fundamentally reconfigures the photophysical behavior. In addition to inducing a red shift in the absorption spectrum by narrowing the HOMO–LUMO energy gap, it more importantly converts the excitation character from a localized excitation (LE) state, which is unfavorable for charge separation, to an intramolecular charge transfer (ICT) state with well-separated spatial distribution. This efficient ICT pathway effectively suppresses electron–hole recombination, thereby significantly prolonging the lifetime of photogenerated charge carriers and ultimately facilitating efficient photocatalytic H2O2 production, while also providing a valuable guideline for the rational design of COF-based systems toward efficient photocatalytic H2O2 generation.
Zhihui Sun, Jiajia Li, Long-Yang Yang et al.· ACS Applied Energy Materials· 0 citations
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