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This document is a reply to a previous article by Brandani et al. regarding diffusion anomalies in nanopores. The authors of this reply provide a comprehensive response to the points raised by Brandani et al. They discuss the limitations of the dual-resistance model (DRM) in decoupling surface barriers and intracrystalline diffusion based on theoretical analysis. The authors also present their own experimental data and calculations to support their findings. They acknowledge the challenges in comparing experimental results with molecular dynamics simulations and express gratitude for the funding and support received for their work. [Extracted from the article]

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]

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. [ABSTRACT FROM AUTHOR]

Confinement of molecules in nanoporous crystalline materials results in the unique and diverse characteristics of intracrystalline diffusion and adsorption, which can significantly affect the efficiency of gas separation and/or catalysis. However, understanding the interplay between confinement and intracrystalline diffusion and adsorption remains elusive at the quantitative level. In this work, it is found that the intracrystalline diffusion could be related to the hopping rate, which might be further connected to the translational and rotational motion of molecules and quantified by corresponding partition functions. Based on this analysis, the correlations capable of predicting the intracrystalline diffusivity and the adsorption entropy are developed. It is shown that the correlations can well capture the experimental and simulation results of more than 20 frameworks, including zeolites and MOFs, for a wide range of guest molecules. This approach can potentially serve as rapid screening tool for nanoporous crystalline materials in gas separation and catalysis. [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]

A coke distribution model of catalyst particles in three‐dimensional space was developed based on population balance theory, and an analytic expression of coke distribution for zero‐dimensional time‐independent problem was deduced. The expression shows that the coke distribution is determined by the average catalyst residence time, coke deposition (or burning) rate, and coke distribution of catalyst inflow. The coke distribution model was further applied to the methanol to olefins (MTO) process. The critical factors influencing coke distribution in MTO process, as well as the effect of coke distribution on product selectivity, were investigated. Three scales of MTO fluidized bed reactor–regenerator systems, i.e., pilot‐scale, demonstration‐scale and commercial‐scale with the reactor diameter of 0.261, 1.25, and 10.5 m, respectively, were simulated. The simulated results were in good agreement with the operation data. The model could be helpful in the operation optimization and reactor design. © 2018 American Institute of Chemical Engineers AIChE J, 65: 1149–1161, 2019 [ABSTRACT FROM AUTHOR]