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Ammonia borane (AB) with 19.6 wt % H2 content is widely considered a safe and efficient medium for H2 storage and release. Co‐based nanocatalysts present strong contenders for replacing precious metal‐based catalysts in AB hydrolysis due to their high activity and cost‐effectiveness. However, precisely adjusting the active centers and surface properties of Co‐based nanomaterials to enhance their activity, as well as suppressing the migration and loss of metal atoms to improve their stability, presents many challenges. In this study, mesoporous‐silica‐confined bimetallic Co−Cu nanoparticles embedded in nitrogen‐doped carbon (CoxCu1−x@NC@mSiO2) were synthesized using a facile mSiO2‐confined thermal pyrolysis strategy. The obtained product, an optimized Co0.8Cu0.2@NC@mSiO2 catalyst, exhibits enhanced performance with a turnover frequency of 240.9 molH2 ⋅ molmetal ⋅ min−1 for AB hydrolysis at 298 K, surpassing most noble‐metal‐free catalysts. Moreover, Co0.8Cu0.2@NC@mSiO2 demonstrates magnetic recyclability and extraordinary stability, with a negligible decline of only 0.8 % over 30 cycles of use. This enhanced performance was attributed to the synergistic effect between Co and Cu, as well as silica confinement. This work proposes a promising method for constructing noble‐metal‐free catalysts for AB hydrolysis. [ABSTRACT FROM AUTHOR]

Elucidating the synergistic catalytic mechanism between multiple active centers is of great significance for heterogeneous catalysis; however, finding the corresponding experimental evidence remains challenging owing to the complexity of catalyst structures and interface environment. Here we construct an asymmetric TeN2–CuN3 double-atomic site catalyst, which is analyzed via full-range synchrotron pair distribution function. In electrochemical CO2 reduction, the catalyst features a synergistic mechanism with the double-atomic site activating two key molecules: operando spectroscopy confirms that the Te center activates CO2, and the Cu center helps to dissociate H2O. The experimental and theoretical results reveal that the TeN2–CuN3 could cooperatively lower the energy barriers for the rate-determining step, promoting proton transfer kinetics. Therefore, the TeN2–CuN3 displays a broad potential range with high CO selectivity, improved kinetics and good stability. This work presents synthesis and characterization strategies for double-atomic site catalysts, and experimentally unveils the underpinning mechanism of synergistic catalysis. Elucidating the synergistic catalytic mechanism involving multiple active centers is of great significance for heterogeneous catalysis. Here the authors construct an asymmetric TeN2–CuN3 double atomic site catalyst featuring synergistic CO2 activation and H2O dissociation for CO2 electroreduction. [ABSTRACT FROM AUTHOR]

The production of hydrocarbons for the synthesis of readily available energy and multifunctional materials is of great importance in modern society. Zeolites have proven to be a boon for the targeted regulation of specific hydrocarbon as shape‐selective catalyst in converting carbon resources. Yet our mechanistic understanding and quantitative description of shape‐selectivity of zeolite catalysis remains rather limited, which restricts the upgrade of zeolite catalysts. Herein, we proposed quantitative principle of shape‐selectivity for zeolite catalysis using methanol‐to‐hydrocarbons (MTH) as model. Combining with molecular simulations and infrared imaging, we unveil the competition of thermodynamic stability, preferential diffusion and favored secondary reactions between different hydrocarbons within zeolite framework are the essence of zeolite shape‐selective catalysis. Notably, we provide methodology to in silico search for the optimal combination of framework topology and acidity properties of zeolites with operating conditions that potentially outperform commercial MTH catalysts to achieve high selectivity of desired hydrocarbon products. [ABSTRACT FROM AUTHOR]

Converting CO2 into carbonaceous fuels via photocatalysis represents an appealing strategy to simultaneously alleviate the energy crisis and associated environmental problems, yet designing with high photoreduction activity catalysts remains a compelling challenge. Here, combining the merits of highly porous structure and maximum atomic efficiency, we rationally constructed covalent triazine-based frameworks (CTFs) anchoring copper single atoms (Cu−SA/CTF) photocatalysts for efficient CO2 conversion. The Cu single atoms were visualized by high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) images and coordination structure of Cu−N−C2 sites was revealed by extended X-ray absorption fine structure (EXAFS) analyses. The as-prepared Cu−SA/CTF photocatalysts exhibited superior photocatalytic CO2 conversion to CH4 performance associated with a high selectivity of 98.31%. Significantly, the introduction of Cu single atoms endowed the Cu−SA/CTF catalysts with increased CO2 adsorption capacity, strengthened visible light responsive ability, and improved the photogenerated carriers separation efficiency, thus enhancing the photocatalytic activity. This work provides useful guidelines for designing robust visible light responsive photoreduction CO2 catalysts on the atomic scale. [ABSTRACT FROM AUTHOR]

Differentiating the diffusivity in straight channel and sinusoidal channel of ZSM‐5 zeolite is a prerequisite for catalyst optimization for the required product distribution with specific orientation. Herein, the intracrystalline diffusivities of n‐butane and iso‐butane in power ZSM‐5 zeolite were investigated by pulse field gradient (PFG) NMR, respectively. Different diffusion behaviors of the selected isomers were revealed. The effective self‐diffusion coefficient of n‐butane is about three orders of magnitude higher than that of iso‐butane. For the selected isomers, the opposite loading‐dependence were presented in self‐diffusion coefficients. Moreover, an equation containing diffusion tensors in different directions in orthogonal coordinate was successfully applied to fit the diffusion coefficients of n‐butane in straight and sinusoidal channel of ZSM‐5, respectively. The diffusivity of n‐butane in straight channel is nearly one order of magnitude faster than that in sinusoidal channel, predicting its dominant diffusion path. [ABSTRACT FROM AUTHOR]

Constructing nanoreactors with multiple active sites in well-defined crystalline mesoporous frameworks is an effective strategy for tailoring photocatalysts to address the challenging of CO 2 reduction. Herein, one-dimensional (1-D) mesoporous single-crystal TiO 2 nanorod (MS-TiO 2 -NRs, ≈110 nm in length, high surface area of 117 m 2 g -1 , and uniform mesopores of ≈7.0 nm) based nanoreactors are prepared via a droplet interface directed-assembly strategy under mild condition. By regulating the interfacial energy, the 1-D mesoporous single-crystal TiO 2 can be further tuned to polycrystalline fan- and flower-like morphologies with different oxygen vacancies (O v ). The integration of single-crystal nature and mesopores with exposed oxygen vacancies make the rod-like TiO 2 nanoreactors exhibit a high-photocatalytic CO 2 reduction selectivity to CO (95.1%). Furthermore, photocatalytic cascade nanoreactors by in situ incorporation of CuW 6 O 24 (W-Cu) clusters onto MS-TiO 2 -NRs via O v are designed and synthesized, which improved the CO 2 adsorption capacity and achieved two-step CO 2 -CO-CH 4 photoreduction. The second step CO-to-CH 4 reaction induced by W-Cu sites ensures a high generation rate of CH 4 (420.4 µmol g -1 h -1 ), along with an enhanced CH 4 selectivity (≈94.3% electron selectivity). This research provides a platform for the design of mesoporous single-crystal materials, which potentially extends to a range of functional ceramics and semiconductors for various applications., (© 2024 Wiley‐VCH GmbH.)

Rational designing electrocatalysts is of great significance for realizing high-efficiency H 2 production in the water splitting process. Generally, reducing the usage of precious metals and developing low-potential nucleophiles oxidation reaction to replace anodic oxygen evolution reaction (OER) are efficient strategies to promote H 2 generation. Here, NiS-coated nickel-carbon nanofibers (NiS@Ni-CNFs) are prepared for low-content Pt deposition (Pt-NiS@Ni-CNFs) to attain the alkaline HER catalyst. Due to the reconfiguration of NiS phase and synergistic effect between Pt and nickel sulfides, the Pt-NiS@Ni-CNFs catalyst shows a high mass activity of 2.74-fold of benchmark Pt/C sample. In addition, the NiS@Ni-CNFs catalyst performs a superior urea oxidation reaction (UOR) activity with the potential of 1.366 V versus reversible hydrogen electrode (RHE) at 10 mA cm -2 , which demonstrates the great potential in the replacement of OER. Thus, a urea-assisted water splitting electrolyzer of Pt-NiS@Ni-CNFs (cathode)||NiS@Ni-CNFs (anode) is constructed to exhibit small voltages of 1.44 and 1.65 V to reach 10 and 100 mA cm -2 , which is much lower than its overall water splitting process, and presents a 6.5-fold hydrogen production rate enhancement. This work offers great opportunity to design new catalysts toward urea-assisted water splitting with significantly promoted hydrogen productivity and reduced energy consumption., (© 2023 Wiley-VCH GmbH.)

Mass transfer of guest molecules has a significant impact on the applications of nanoporous crystalline materials and particularly shape-selective catalysis over zeolites. Control of mass transfer to alter reaction over zeolites, however, remains an open challenge. Recent studies show that, in addition to intracrystalline diffusion, surface barriers represent another transport mechanism that may dominate the overall mass transport rate in zeolites. We demonstrate that the methanol-to-olefins (MTO) reaction can be modulated by regulating surface permeability in SAPO-34 zeolites with improved chemical liquid deposition and acid etching. Our results explicitly show that the reduction of surface barriers can prolong catalyst lifetime and promote light olefins selectivity, which opens a potential avenue for improving reaction performance by controlling the mass transport of guest molecules in zeolite catalysis., (© 2020 Wiley-VCH GmbH.)