Catalytic Materials (United States)

Biodiversity data linkage is a prerequisite for addressing pressing societal and research questions. Digitisation of resources has progressed rapidly, but this has led to a number of parallel approaches for datasets and services, making it difficult for users to identify the appropriate tool for their requirements. While scientific names are a key element for data linkage, they are not fully suited to this role. Many of them are not unique identifiers for taxa (such as the species that form the basic building block of a large part of biodiversity information) because taxonomic research has resulted in name changes. Likewise, usage is prone to errors like misspellings or misapplication of nomenclatural rules. This complexity and unreliability may demotivate data providers from readying their valuable datasets for integration into an interlinked landscape of biodiversity information. Correct linking of scientific names is an important element in this process of linking data from various sources. Aggregated taxonomic datasets and name-matching services are an essential infrastructure to build tools for this purpose and are increasingly using unique, resolvable and persistent name identifiers. Accessing the aggregated dataset via these identifiers can also display connections between the names within the dataset, linking, orthographic variants to correct spelling, synonyms to accepted taxon name etc. External datasets that hold valuable research and usage information as taxon-associated data can also be linked directly via these identifiers. This helps them to meet the FAIR data criteria (Findable, Accessible, Interoperable, Reusable). Name matching finds the aggregator's name identifier, adding this identifier to the local data record may help to further interconnect biodiversity information, if data providers are motivated to partake in this process of enabling data linkage. We posit that this motivation can be increased by simplifying the process of choosing the right method for their specific needs, which may vary widely. We thus propose a framework that helps users to select the optimal workflow to address these needs. This involves: (i) identifying and categorising the specific criteria that characterise different user needs; (ii) based on these criteria, defining the necessary metadata both for taxonomic datasets accessed by name-matching services and the name-matching services themselves; (iii) providing tools based on these metadata that will allow users to interactively and confidently choose the best-fit target dataset and name matching service for their specific purpose.

Selective activation of CH4 under mild conditions to produce liquid oxygenates is central to low-carbon chemical manufacturing. While O2 or H2O2 are commonly used oxidants, the direct oxidizing role of H2O itself remains poorly defined. Here, we use Au–TiO2 as a prototypical nanointerface to disentangle the effects of H2O versus O2 on photocatalytic CH4 oxidation. In-situ EPR spin-trapping, high-pressure DRIFTS, and DFT reveal two distinct pathways. With H2O as the sole oxidant, photogenerated holes oxidize H2O to •OH, which abstracts H from CH4 to form •CH3; subsequent surface reactions yield CH3OH and HCHO. Computations indicate that roughly one-third of the generated •OH participates effectively in the productive sequence. In contrast, when O2 is present, interfacial electrons preferentially reduce O2 to •OOH; coupling of •OOH with •CH3 forms CH3OOH intermediates that evolve to CH3OH/HCHO, but the elevated •OOH flux also accelerates deep oxidation to CO2 and suppresses H2 evolution. These mechanistic differences in radical identity, intermediate pools, and apparent barriers translate into divergent selectivity. Under optimized, O2-free conditions (1 wt % Au–TiO2, 80 °C, 20 bar CH4, UV–vis; H2O as oxidant/medium), liquid C1 oxygenates are obtained at 7.7 mmol g–1 h–1 with 100% selectivity. The study reveals that tuning the oxidant and the interfacial radical landscape at a nanoscale metal–oxide interface governs the precision activation of CH4 and provides mechanistic insight into H2O-driven, selective methane oxidation on Au–TiO2.

Since the 20th century, massive CO2 emissions from fossil fuel combustion have intensified the global climate crisis. The efficient conversion of CO2 into high-value multicarbon (C2+) products represents a central challenge for energy system transformation. Among various technologies, electrocatalytic CO2 reduction (CO2RR) is recognized as the most promising route due to its tunable pathways and compatibility with renewable energy. Copper-based materials stand out as the only metal catalysts capable of selectively producing hydrocarbons and oxygenate from CO2 in aqueous electrolytes, yet they suffer from insufficient selectivity and stability. This review systematically examines the advanced strategy of optimizing copper-based CO2RR catalysts through confinement effect engineering. Distinct from prior perspectives treating confinement as a secondary feature, this work establishes it as a primary design principle, which creates tailored microenvironments enabling synergistic spatial constriction and electronic regulation to precisely steer reaction pathways. A comprehensive summary is provided on diverse catalyst architectures constructed via confinement engineering (e.g., core–shell assemblies, porous frameworks, and nanocavities), with an in-depth discussion of the fundamental mechanisms─including intermediate enrichment, electronic structure modulation, and dynamic stability reinforcement, which underpin the enhanced activity, C2+ selectivity, and durability. Current challenges regarding the dynamic evolution of confined microenvironments and industrial scalability are outlined. Future research directions involving cross-scale design, integrated characterization modeling, and process innovation are proposed. This review aims to provide a robust theoretical foundation and clear technical pathway for designing highly efficient and stable confined catalytic systems, thereby accelerating the practical implementation of CO2 conversion technologies.

Chlorine evolution reaction (CER) is pivotal to the chlor-alkali industry, while its operation still relies on the dimensionally stable anode (DSA) developed decades ago, which is hindered by high costs, moderate selectivity, and limited energy efficiency. Here, we present a spinel-type hexavalent iridium single-site electrocatalyst (spinel-iso-IrVI) via strategic modulation of delocalized electron distribution that demonstrates exceptional CER performance. This catalyst operates with an ultralow overpotential of 27mV at 10mA cm-2 (57mV for commercial DSA), a nearly 100% CER selectivity across a wide potential range, and a record energy efficiency of 83.5% at an industrial-level current density of ∼300mA cm-2. At the overpotential of 100mV, spinel-iso-IrVI delivers a mass activity of 9671mA mgRu+Ir -1 and a turnover frequency of 0.278 s-1, surpassing those of the benchmark DSA by over 386-fold and 20-fold, respectively. The high-performance of spinel-iso-IrVI results in a low production cost of US$0.04 per kilogram of chlorine. Mechanism studies reveal a two-step chemical-electrochemical cycle reaction mechanism, in which the chemical reaction step involves a spontaneous redox reaction triggered by hexavalent IrVI sites. This process enables the spontaneous adsorption, bonding, and oxidation of Cl- to generate Cl2, thereby significantly boosting the reaction kinetics.

Nitrogen oxides (NOx) are harmful air pollutants, and their selective catalytic reduction by CO (CO-SCR) offers the dual benefit of removing both NO and CO, thus realizing the concept of “waste-to-value”. However, most CO-SCR catalysts are effective only at ≥300 °C, limiting low-temperature applications. Herein, we explore Ni–Cu mixed oxides (NiCuOx) that leverage the synergistic roles of Cu+ species and the Ni3+/Ni2+ redox cycle and the surface synergistic oxygen vacancies (SSOVs) that facilitate NO dissociation. NiCuOx catalysts were synthesized using three conventional methods─sol–gel, coprecipitation, and hydrothermal─as well as a less conventional microwave-assisted deep eutectic solvent (DES) method, and their CO-SCR performance was systematically evaluated. Among them, the DES-derived catalyst (DES-NiCuOx) exhibits superior catalytic performance, achieving 100% NO conversion above 120 °C and 100% N2 selectivity above 150 °C, ranking among the highest reported to date for nonprecious metal catalysts. This outstanding activity is attributed to its larger specific surface area; enriched Cu+ species and OVs, particularly SSOVs; and improved redox properties. In situ DRIFTS analysis reveals that interfacial Ni3+–□–Cu+ (where □ represents an OV) structures in DES-NiCuOx promote NO dissociation and CO adsorption. Moreover, the concurrent involvement of Langmuir–Hinshelwood and Mars–van Krevelen mechanisms, facilitated by excellent oxygen mobility and redox properties, plays a vital role in enhancing low-temperature CO-SCR efficiency. This work highlights the advantages of the DES synthesis route for preparing highly dispersed mixed metal oxides and provides new insights into the rational design of efficient catalysts for low-temperature NOx abatement.

Computational modeling of electrocatalysis has long relied on static representations of the electrode–electrolyte interface and thermodynamic descriptors. While these conventional approaches provide valuable insights, they inherently treat the interfacial environment as rigid and passive, overlooking its dynamic and responsive nature under operational conditions. Yet, the actual electrochemical interface is a complex and dynamic entity, where the solvent, adsorbates, ions and electrode surface engage in a continuous interplay, driven by the applied potential. Capturing this dynamic interfacial microenvironment is therefore essential for a realistic understanding of electrocatalytic mechanisms. In this Perspective, we discuss how explicit simulations of the interfacial microenvironment─particularly through methods like ab initio molecular dynamics that incorporate solvent, ions, and potential effects─enables the direct visualization and analysis of concerted dynamics and transient states that are difficult to intuit or predefine. Such simulations provide an atomic-scale “movie” of the evolving interface, offering critical insights into: (1) the active participation of the solvent network in stabilizing or mediating reaction intermediates, (2) the potential dependence of free energy profiles, and (3) the cooperative role of electrolyte components in electrocatalytic steps. We emphasize that explicit, dynamic simulation of the interfacial microenvironment is essential for capturing the synergistic, potential-driven complexity of real electrochemical interfaces. This not only refines predictions from static models but can sometimes reveal hidden mechanisms, thereby advancing the interpretation of reaction pathways and supporting the rational design of efficient electrocatalysts.

We report the synthesis, structures, and magnetic properties of a new family of thiocyanate-bridged binuclear cobalt(II) complexes, [Co2(Xphtpy)2(μ-SCN)2(SCN)2] (Xphtpy = 4′-(4Xphenyl)-2,2′:6′,2″-terpyridine, X = Cl, Br, I), with varying terminal halides in the halogen-functionalized terpyridine ligands. Single-crystal X-ray crystallography reveals that these complexes crystallize in the same monoclinic system P1 space group with nearly identical structural features. Additionally, the structural distortion around the Co2+ centers is highly similar, making the halogen-substituent effect play a critical role in tuning the magnetic anisotropy and couplings. Interestingly, the two Co(II) centers are bridged by two SCN– atoms in a reverse parallel mode. Magnetic studies reveal ferromagnetic interaction transferred by thiocyanates between the Co2+ ions and the strength of this interaction decreases as the ligand field on the pseudo-octahedral Co(II) center decreases from Cl– > Br– > I–. Both density functional theory and ab initio calculations show that individual Co(II) centers show giant positive D values, and simulation of magnetic susceptibility predicts a dominant ferromagnetic interaction between these Co(II) centers in all complexes. Ab initio calculations predict that both the magnitude of the D value for individual Co(II) centers and the strength of this magnetic exchange interaction between the Co(II) centers increase as we move toward heavier halides.

Secure information encryption is paramount in modern society for data protection, anticounterfeiting, and confidential communication. Here, we report the first demonstration of radiochromic metal-organic frameworks (MOFs) for high-security information encryption, leveraging their unique X-ray-induced chromic responses. Three thorium-based MOFs (Htpc⊂TOF, Hmpc⊂TOF, and Hpybz⊂TOF) were rationally constructed by embedding distinct pyridine-derived guest molecules within a robust layered Th6(μ3-O)4(μ3-OH)4(HCOO)12(DMF)2·2DMF host framework. Remarkably, upon X-ray irradiation, each framework exhibits well-defined and distinguishable color transformations, including purple for Htpc⊂TOF, yellow for Hmpc⊂TOF, and green for Hpybz⊂TOF, while Htpc⊂TOF additionally responds to ultraviolet (UV) light, enabling dual-stimuli activation. This hierarchical, sequential chromic switching facilitates multilevel decryption, significantly enhancing encryption complexity and thwarting unauthorized access. Proof-of-concept demonstrations, including barcodes, QR codes, and 3D color matrices, illustrate the potential of these MOFs for spatially encoded, temporally controlled, and multidimensional information encryption. The frameworks exhibit excellent chemical, thermal, and radiative stability, maintaining structural integrity under different conditions, including high dose ionizing radiation, heating to 200 °C, and prolonged water exposure. Collectively, these findings establish a new paradigm for robust, stimuli-responsive MOFs, marking the first use of radiochromism in advanced information encryption technology.

We report an enantioselective 1,2-arylamination of unactivated alkenes catalyzed by a chiral indenyl-Rh-(III) complex using Troc-protected hydroxylamine derivatives. This method enables efficient access to structurally diverse 2-aminotetralin scaffolds and amino-substituted carbospirocycles via a 6-endo cyclization involving electrophilic aromatic substitution (EAS). Experimental and computational studies reveal that the electronic asymmetry of the chiral indenyl ligand plays a pivotal role in enhancing catalytic activity compared to cyclopentadienyl-based analogs. Furthermore, the identity of the N-protecting group on hydroxylamine significantly influences the reaction pathway, distinguishing this transformation from previously reported aziridination strategies. The synthetic utility and versatility of this catalytic system are further demonstrated through streamlined syntheses of biologically relevant molecules, highlighting its strong potential for applications in medicinal chemistry.