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The coupling conversion of CO/CO2 (CO x ), sourced from coal, natural gas, biomass, and other carbon sources, with substrates of alcohols, ethers, olefins and alkanes to produce valuable chemicals represents an attractive catalytic route for the direct utilization of CO x carbon atoms. The majority of traditional CO x conversion processes rely on hydrogenation or carbonylation reactions with metal catalysis. To date, zeolites containing protons in specific atomic scale channels or cages have emerged as one of the most important non-metallic heterogeneous catalysts for the direct coupling of CO x with a range of substrates (e.g., alcohols, ethers, olefins and alkanes), yielding products such as acids, esters, ketenes, and aromatics. Different from metal-based catalysis, zeolite-catalyzed CO x coupling reactions generally proceed with alkyl cations and acyl cations as key intermediates, the stabilization of which is significantly enhanced within the intrinsic confined zeolitic reaction spaces. Typical processes include dimethyl ether (DME) carbonylation to methyl acetate (MAc), dimethoxy methane (DMM) carbonylation to methyl methoxyacetate (MMAc), olefin carbonylation to branched acids, the reaction of alkanes with CO x to aromatics, etc. These cases demonstrate the great potential of zeolite in promoting efficient CO x coupling. However, despite recent advances in mechanistic studies on DME carbonylation, the fundamental chemistry underlying zeolite-catalyzed CO x coupling across widely applied catalytic systems remains insufficiently understood. In this perspective, we summarize decades of research on CO x coupling catalysis over zeolites, including reaction mechanisms, catalytic cycles, reaction kinetics and the structure-performance relationships. We also propose future outlooks for achieving a systematic and in-depth understanding of zeolite-catalyzed CO x coupling chemistry, optimizing current processes and developing new CO x coupling processes.
In this study, we developed a novel monolithic heating method by utilizing electromagnetic induction to enhance carbon nanotube (CNT) production from plastic waste via pyrolysis-catalysis. Metal porous catalysts, including iron (Fe), nickel (Ni) and Fe-Ni alloy, enabled rapid volumetric heating, improved catalytic efficiency and reduced energy consumption compared with conventional methods. The porous Fe catalyst demonstrated superior CNT yield, while Ni provided the highest hydrogen (H2) production. We achieved carbon-recovery efficiencies of 86%, 84% and 82% for low-density polyethylene, high-density polyethylene and polypropylene, respectively, by using the Fe catalyst. Our economic analysis indicated that CNT production from waste polyethylene and waste polypropylene is feasible, with break-even selling prices of $4.02 and $4.87 kg-1, respectively. Our work supports the development of a circular economy by enabling the efficient conversion of plastic waste into valuable CNTs and H2 via pyrolysis-catalysis.
The inability to achieve the selective recognition of specific chiral molecules or polarized photons has significantly hindered the application of conventional photocatalysts in asymmetric synthesis. To address this challenge, we have designed and synthesized discrete chiral BiOCl/BiOBr hybrid semiconductors with multilevel chirality, ranging from atomic-scale lattice distortion to microscale fan-blade-like plates and geometrically chiral superstructures. These hierarchically chiral semiconductors enable the polarization-dependent photodegradation of chiral tetracycline (TC) molecules. Under dark conditions, the L-BiOCl/BiOBr hybrids exhibit stronger adsorption for TC than their D counterparts, which can be attributed to conformational energy differences. Strikingly, under right-, left-, and linearly polarized light (RCP, LCP, and LP), the L-hybrids achieve TC degradation rates that are 19.3, 12.0, and 3.3 times higher, respectively, than those of the achiral reference. A similar polarization-dependent trend is observed for the D-hybrids. Combined DFT simulations and circularly polarized photocurrent measurements confirm that this photon-selective asymmetric catalysis originates from the synergistic interplay of an atomic-level chiral structure, polarized-light response, and spin-polarized charge separation. Moreover, L-BiOBC0.33 and D-BiOBC0.33 exhibit the same polarized photon-selective chiral catalytic behavior toward the degradation of chiral ofloxacin. This work establishes a paradigm for designing efficient chiral photocatalysts with hierarchical chirality, providing a route for tailoring nanomaterials for selective light-matter interactions and spin-polarized catalysis, with potential applications in chiral synthesis and chiral nanophotonics.
Volatile organic compounds (VOCs) are major precursors of ozone and PM2.5, playing a crucial role in the formation of photochemical smog and haze. Their persistence not only aggravates air pollution but also poses serious risks to human health. Therefore, the development of efficient VOCs abatement technologies is essential for environmental protection and public health. However, conventional single recovery or destruction approaches often suffer from inherent limitations, making deep purification difficult to achieve. In recent years, low-temperature plasma (LTP)-based catalytic technologies have gained increasing attention due to their high degradation efficiency and strong mineralization capability. This review provides a comprehensive overview of recent advances in LTP-catalyst systems for VOCs degradation, with a particular focus on the real-time monitoring of reaction intermediates and elucidation of degradation mechanisms. Furthermore, the synergistic integration of LTP with traditional VOCs control technologies, including absorption, adsorption, photocatalysis, and biological treatment, is discussed to demonstrate their enhanced removal performance. Finally, the current challenges and future prospects of LTP-based hybrid systems are summarized to provide theoretical insights and technical guidance for developing next-generation VOCs abatement technologies.
Creating efficient catalytic sites on covalent organic polymers (COPs) is a promising approach for green energy conversion and industrial catalysis. Although the post-synthetic modification of COPs has made progress in constructing single-atom sites and metal nanoparticles, this method remains limited in terms of the types, quantities, and overall performance of the constructing sites. To address these limitations, we develop a template-source construction strategy for catalytic site establishment. This strategy successfully yields hollow COPs with a high content of Co-O active species (H-COP-Co), demonstrating high activity as oxygen electrocatalysts. Comparing to traditional post-synthetically modified COPs with single Co sites (S-COP-Co), H-COP-Co demonstrates an increase in active metal content, from 2.96% to 56.86%, with enhanced catalytic activity for oxygen evolution reaction (OER). Unlike single Co sites that operate via the adsorbate evolution mechanism (AEM), comprehensive spectroscopic characterization and theoretical calculations reveal that the initial and reconstructed Co oxide nanoparticles in COPs operate via the oxide path mechanism, serving as the origin of the superior OER performance. These findings provide valuable insights into the design of multifunctional composite COP materials, underscoring the importance of intrinsically structural designing and modulating reaction mechanisms to enhance energy conversion efficiency.
Oxa-quaternary carbon centers are prevalent in bioactive natural products and pharmaceuticals. However, the development of general and practical methods to construct these oxa-quaternary carbon stereocenters remains a formidable challenge. Herein, we report a desymmetrization strategy for the construction of oxa-quaternary carbon stereocenters based on palladium/chiral norbornene cooperative catalysis. With readily available aryl iodides and prochiral 2'-bromo-aryl-substituted tertiary alcohols as the building blocks, a wide variety of 6H-benzo[c]chromenes bearing an oxa-quaternary carbon stereocenter and a versatile C-Br bond are expediently prepared in a highly enantioselective manner (43 examples, up to 99% e.e.). Notably, both enantiomers can be stereodivergently obtained through a simple switch of the same configurated chiral NBE cocatalysts. The synthetic utility of this method is demonstrated by a successful scale-up experiment and diverse late-stage structural modifications through the facile elaboration of the common C-Br bond of the obtained chiral 6H-benzo[c]chromene products. In addition to the experimental studies, DFT calculations are performed to elucidate the reaction mechanism, the origin of enantiodiscrimination, and enantioselectivity inversion in this desymmetrization process.
We present a type of synergistic catalyst that integrates Frustrated Lewis Pair (FLP) and photocatalytic (PC) functionalities on an atomically precise copper nanocluster. By strategically functionalizing the cluster surface with 6-(dibutylamino)-1,3,5-triazine-2,4-dithiol (TRZ), we successfully synthesize a structurally well-defined nanocluster [Cu20(TRZ)9(4-F3PPh3)2H4]2-. The TRZ ligands serve a triple function: they not only stabilize the nanocluster framework but also furnish nitrogen-based Lewis basic sites. These sites, in conjunction with surface-exposed copper atoms acting as Lewis acids, form FLP-active centers capable of activating small molecules such as silanes under mild conditions. Furthermore, the TRZ ligand's triazine moiety acts as an efficient photoredox unit, driving the photocatalytic production of hydrogen peroxide through oxygen reduction. This activity, when integrated with the FLP functionality, results in an integrated system that exhibits high efficiency and selectivity in the catalytic oxidation of silanes to silanols. The catalyst demonstrates outstanding activity, selectivity, and stability under ambient conditions. This study not only presents a generalizable strategy for embedding FLP-PC bifunctionality in metal nanoclusters but also confirms the feasibility of designing high-performance cluster catalysts that operate via synergistic mechanistic pathways. The integration of FLP and PC functionalities supports efficient and selective transformations relevant to sustainable catalysis.
Mesoporous single-crystal metal oxides are highly attractive for heterogeneous catalysis because they combine high surface accessibility with long-range lattice coherence; however, their synthesis remains fundamentally challenging due to the thermodynamic incompatibility between crystallization and pore formation. Here we report a template-free, energy-driven facet-oriented crystallization strategy that enables the formation of mesoporous single-crystal metal oxides with tunable pore architectures and exposed high-energy facets. Polyvinylpyrrolidone functions simultaneously as a pore maintainer and surface-energy regulator, preserving mesoporosity while selectively stabilizing high-energy facets to direct single-crystal growth. The method is applicable to multiple oxides, including Co3O4, MgO, NiO, and mixed-metal systems. As a representative example, mesoporous single-crystal Co3O4 with preferentially exposed (111) facets exhibits outstanding performance in the selective oxidation of aromatic alkanes, achieving up to 99% conversion and selectivity under mild conditions. Experimental and theoretical analyses suggest that the synergy between mesoporosity and active-facet exposure enhances reactant adsorption, oxygen activation, and reaction kinetics, providing a general design principle for crystallographically defined porous catalysts.
Particle size plays a critical role in governing catalytic activity and selectivity due to the distinct behaviors of different surface sites. However, direct experimental probing of site-specific electrocatalytic activity remains formidably challenging. Here, we employ a correlated scanning electrochemical cell microscopy-transmission electron microscopy (SECCM-TEM) approach to precisely analyze the intrinsic electrocatalytic activities of specific surface atoms (edge versus plane) on individual palladium nanocubes down to 8 nm, using the hydrogen evolution reaction (HER) as a model process. Our measurements reveal that the edge sites exhibit a HER turnover frequency approximately four times higher than that of (100) plane sites. Density functional theory calculations and additional single-particle studies of edge-covered Pd-Au nanocubes further confirm the pivotal role of edge atoms in catalysis. This SECCM-TEM methodology provides unambiguous insights into the distinct catalytic properties of edge and plane sites and can be extended to decipher catalytic active sites in more structurally complex electrocatalysts.
Direct electron transfer (ETP) during peroxymonosulfate (PMS) activation enables selective, matrix-resistant organic contaminants oxidation, yet its precise control over competing radical pathways remains elusive. Here we report a nano-island-like single-atom catalyst- carbon nitride islands immobilize cobalt single atoms on reduced graphene oxide (CoN3C/rGO)- that leverages an island-sea architecture to direct PMS activation toward ETP. Experimental and density functional theory (DFT) analyses show an rGO induced elevation of the Co d-band center and a sharpened dz2 orbital near the Fermi level, promoting directional hybridization with PMS p orbitals and suppressing antibonding occupation. Consequently, CoN3C/rGO/PMS degrade bisphenol A (BPA) completely within 5 min, with ~94% contribution from ETP. Furthermore, catalytic membrane coatings enable stable 100 h continuous operation in diverse real water matrices with minimal Co leaching. Our results demonstrate a design principle-orbital-level modulation via island-sea architectures to reconcile activity and selectivity in Fenton-like systems and advance translating practical water treatment technologies based on single-atom electronic control.
Catalyst activity is typically the primary priority in designing a catalytic system. The higher catalyst activity is envisioned to confer more powerful and effective catalytic performance. Here, we report a heterogeneous double hydrogen bond/photoredox synergistic catalysis, wherein the flexibility and spatial orientation of catalytic centers, rather than catalyst activity, play a dominant role in catalytic performance. We synthesized six metal-organic frameworks (MOFs) with photocatalytic and double hydrogen bond donor (DHBD) centers. MOF-F-TU featuring the relatively flexible (F) thiourea (TU) center has proved most effective in promoting dehalogenation and reductive coupling reactions. In contrast, MOF-R-SQA1 with a stronger but rigid (R) squaramide (SQA1) site exhibits no catalytic activity. Mechanistic studies rationalize this unique phenomenon by implying a cooperative activation of the substrate via its double hydrogen bonding with DHBD and π-π overlapping with photocatalytic center, which is closely associated with the spatial arrangement of synergistic catalytic centers. MOF-F-TU also outperforms homogeneous counterparts, displaying turnover numbers of up to 9500.
Designing tandem catalysts with well-defined interfacial architectures is of great significance for promoting multi-step electrochemical transformations, yet achieving synergistic regulation of dual active sites at the atomic level remains a formidable challenge. Herein, we develop an atomic-level engineering strategy to construct RuOx cluster-modified Cu-based nanowire array electrodes with abundant interfacial structures, which act as efficient tandem catalysts for sustained nitrite-ethanol paired electrolysis at ampere-level current densities. In situ spectroscopic analysis combined with theoretical calculations reveals that the atomically RuOx cluster serves as highly active water-activation sites, generating abundant active hydrogen/oxygen species that subsequently react with adsorbed nitrogen and carbon-containing intermediates, thereby enabling exceptionally favorable co-electrolysis kinetics. Impressively, a membrane electrode assembly flow electrolyzer constructed with RuOx@R-Cu/CF as both electrodes achieves >90% Faradaic efficiencies for NH3 and acetate over a wide current density window of 0.2-1.0 A cm-2, along with high yields of 5.86 mmol h-1 cm-2 (NH3) and 8.65 mmol h-1 cm-2 (acetate) at 1.0 A cm-2, and outstanding operational stability, significantly surpassing previously reported co-electrolysis systems.
Sulfoxaflor (SXF), a novel sulfoximine insecticide, has been widely used as a substitute for traditional neonicotinoids (NEOs) to control piercing-sucking pests in agriculture. However, its environmental persistence, high mobility in water and soil, and potential toxicity to non-target organisms (e.g., honeybees, aquatic invertebrates) as well as the toxic risks of its long-lasting metabolites (e.g., X11719474) have raised significant ecological concerns. Biodegradation, as an environmentally friendly and efficient remediation strategy, plays a crucial role in regulating the environmental fate of SXF, and has become a research hotspot in recent years. This review systematically summarizes the environmental behaviors of SXF, including its migration, transformation, and residue characteristics in water bodies, soils, and agricultural products. It focuses on collating the reported SXF-degrading microorganisms (mainly bacteria such as Ensifer, Pseudomonas, Aminobacter, and cyanobacteria like Synechocystis salina) and their degradation efficiencies under different environmental conditions. Moreover, the review elaborates on the core role of nitrile hydratase (NHase) in SXF biodegradation, including the types, structural characteristics, and catalytic mechanisms of SXF-degrading NHases, as well as the key factors (environmental factors, structural residues, chemical modulators) influencing NHase catalytic activity. Additionally, biotechnological optimization strategies for enhancing SXF biodegradation efficiency, such as heterologous expression and immobilization of NHase, are discussed in detail. Finally, the current research gaps and future research directions are prospected, aiming to provide comprehensive theoretical support for the scientific application and environmental risk control of SXF, and offer references for the biodegradation research of novel NEOs and similar insecticides.
Low-temperature direct ammonia fuel cells (DAFCs) are promising yet challenged by slow ammonia oxidation reaction (AOR) kinetics and severe catalyst poisoning. To address such bottlenecks, we design a vertically aligned NiCo2O4@NiCo2S4 core-shell heterostructure where the NiCo2S4 shell stands for NH3 activization and the NiCo2O4 core serves for N2 generation. The built-in electric field at the heterointerface, together with the bimetallic synergy introduced by Ni doping, enables the optimization of electron configuration via work function engineering. Driven by the adsorption energy gradient across heterointerface, the efficient *N spillover promotes the regeneration of NH3 adsorption sites and facilitates the efficient desorption of N2, leading to a refined tandem catalytic pathway of NH3-*N-N2. Consequently, NiCo2O4@NiCo2S4 achieves a high current density of 972 mA cm-2 at 80 °C in a three-electrode system and delivers 20-h stability, offering a novel strategy for high-performance, poison-tolerant AOR anodes.
Facial stereoselective transformations of bicyclic compounds offer streamlined access to conformationally constrained scaffolds that are valuable in catalysis, materials science and drug discovery. Owing to the higher electron density of the highest occupied molecular orbital on the exo-face, norbornadiene (NBD), a typical bicyclic molecule, undergoes most reactions on its more accessible exo-face, whereas reactions on the endo-face remain underdeveloped. Here we report a nickel(0)-catalysed endo-stereoselective [2+2] cycloaddition of NBDs with unactivated internal alkynes, enabled by ligand-mediated facial differentiation of NBDs and nickel-controlled configuration of a key intermediate. This method provides an expedient pathway to important scaffolds, including endo-tricyclononadienes and substituted homocubanes, with excellent atom economy. The utility of this scalable reaction is demonstrated through applications of the products in asymmetric catalysis and in the synthesis of drug analogues.
Over the past decades, yeast surface display (YSD) technology has emerged as a powerful biotechnological tool with broad applications in biomedicine, industrial catalysis, and environmental science. However, its efficiency, stability and applicability are often limited by proteolytic degradation during secretion in commonly used strains and steric hindrance associated with anchoring architectures. In this study, we developed a high-performance platform, "CEN-Display," using a systemic engineering strategy on the Saccharomyces cerevisiae CEN.PK2-1C strain to expand the YSD toolbox for new chassis. The host chassis was engineered by deleting key vacuolar proteases PEP4/PRB1 to suppress degradation and CAN1 to modulate membrane permeability. And the redesigned display vector incorporated a de novo designed rigid linker (>600 aa) to minimize steric hindrance. Moreover, we conducted a systematic evaluation of eight candidate GPI-anchored proteins and refined cultivation process, specifically optimizing initial inoculation density and induction timing. Eventually, we identified 28_YI as a highly efficient and stable anchor, achieving a sixfold increase in α-galactosidase display efficiency and a 63.5% enhancement in enzymatic activity relative to the conventional Aga1-Aga2 system. Furthermore, the CEN-Display platform exhibited robust compatibility and stability for displaying both the complex enzyme (β-glucosidase, BGL1) and the degradation-prone nanobody (VHH 7D12). Collectively, this work establishes a high-performance yeast surface display platform based on the CEN.PK chassis and provides a foundation for the construction and application of high-performance display systems with broad utility in protein engineering and functional screening.
Understanding the structure-performance relationship for the selective generation of reactive oxygen species is critical in Fenton-like catalysis research. Single-atom catalysts (SACs) anchored on nanocarriers can maximize their catalytic capacity, but the inherent high curvature of nanocarriers may induce strain of active sites with unclear impact on their catalytic performance. Here, we uncover the strain-dependent reactivity of single-atom FeN4 sites anchored on carbon nanotubes (CNTs) for peroxymonosulfate (PMS) activation. Density functional theory calculations show that the curvature-induced strain of CNTs distorted the FeN4 geometry and redistributed its electronic structure, thereby steering PMS activation toward a singlet oxygen (1O2) pathway. Experimental validation confirms that FeN4-CNTs with an 8 nm diameter achieved the highest degradation rate of sulfamethazine in a PMS activation system with exclusive 1O2 selectivity, which was 7.2 and 5.4 times that of counterparts on 2 and 50 nm CNTs, respectively. Spectroscopic and theoretical analyses reveal that rational strain enhanced Fe-3d and O-2p coupling, facilitating electron transfer and elongating O-H bonds in PMS to promote 1O2 generation. This work elucidates the mechanistic origin of strain effects in single-atom catalysis and highlights strain engineering as a powerful strategy for selective PMS activation and high-efficiency environmental catalysis.
Biomass catalytic gasification studies often focus on either inherent metal catalysis or impregnated metal catalysis rather than their integrated roles. Thereby, this study focused on analyzing the integrated catalytic roles of inherent and impregnated metals of biochar on the steam gasification of grass biomass. Monometallic and bimetallic impregnations of nickel (Ni) and iron (Fe) on the biomass and char preparation at a pyrolysis temperature of 500 °C (i.e., Napier grass biochar (NGC500) were performed. Then the catalytic performance and synergistic effect on H2-rich syngas production from steam co-gasification with herbaceous biomass (i.e., Giant Miscanthus (GM)) were investigated, in which the reactions were basically conducted at 750 °C with 0.05 g/min steam flow and 1 h holding time in a vertical fixed bed gasifier. It is found that, by the addition of the bimetallic Ni-Fe-NGC500 into the co-gasification system, the highest H2-rich syngas yield was achieved with the maximum of 95 mmol/g-daf. The kinetic analysis based on time-resolved syngas profiles showed the highest H2 production rate with intermediate kinetic behavior. Also, the inherent K in NG plays a vital role in catalyzing the reactions in parallel with impregnated metals. Especially, the formation of Ni0.23Fe0.22 alloy in the bimetallic biochar sample is found to be favorable in achieving synergy effect during gasification whereas the inherent K in the NGC can easily react with CO2, H2O and silicates in the media yielding beneficial gaseous products, and ultimately forming K-aluminosilicates (KAlSi3O8) to reduce the catalytic effect.
Iron oxidation is a fundamental chemical transformation underpinning planetary evolution and technologies ranging from steel metallurgy and corrosion to catalysis and magnetic storage. Despite decades of surface-science research elucidating oxidation kinetics and surface dynamics, the atomic-scale transformations occurring beneath the surface during the incipient stages of oxidation have remained largely inaccessible. Here we directly visualize the atomic genesis of iron oxidation using in situ environmental scanning/transmission electron microscopy (ETEM/ESTEM). We reveal that oxidation begins with the nucleation of an epitaxial FeO layer on metallic iron. Once the FeO film reaches a critical thickness, a lattice-template-driven phase transformation is triggered at the buried FeO/Fe interface, rather than at the gas-exposed surface, leading to the formation of the higher-valence oxide phase Fe3O4. This interfacial transformation drives a concerted outward flux of iron cations, continuously regenerating a ∼two-monolayer FeO skin atop a thickening Fe3O4 underlayer. This process results in a persistent, self-regulating FeO/Fe3O4/Fe trilayer architecture that directly contradicts the prevailing assumption that oxidation states monotonically increase toward the gas-solid interface. By identifying this counterintuitive, interface-driven mechanism, our results provide the missing atomic-scale link for understanding oxide stability and phase evolution in reactive environments.
Supported nanoparticles fabricated by an ex-solution process from perovskite scaffolds serve promising capabilities for various thermal and electrochemical reactions. Although the size distribution of the nanoparticles plays a crucial role in catalysis, it remains difficult to control in ex-solution due to the lack of understanding of their underlying energetic factors. Here, we investigate the impact of B-site doping in two different types of perovskite hosts (A2+B4+O3 and A3+B3+O3) on the size distribution of ex-solved nanoparticles. By incorporating non-reducible ions at the B-site, we observe the variations in nanoparticles' sizes and densities using model cleaved surfaces of ceramic pellets. Density functional theory calculations help correlate the observed experimental results with the computed energetic descriptors, providing deeper insights into the particle ex-solution and enabling the description of particle density via a first-order nucleation model. Furthermore, we utilize the tailored ex-solution materials as catalysts for N2O decomposition, and it exhibits a volcano-plot relationship between the catalytic activity and size distribution of ex-solution particles. It suggests that our findings can provide an alternative way to optimizing catalytic active sites for various environmental and energy applications.