Controlled construction of hierarchical porous carbon catalysts with Co/CoFe interfaces via Zn sacrifice and Prussian blue analogue growth for oxygen evolution.

Preparation of Cu-loaded porous metal oxide catalysts for the catalytic upgrading of wood tar in supercritical methanol

Nanoscale simulation of water-to-ice phase change in porous catalyst layers of fuel cells under direct cold startup condition

Pore-scale investigation of heat and mass transport in porous catalyst layers based on an orthogonal design method

Graphene Quantum Dots-Bridged Fe-Ce Bimetallic Aerogel Catalyst for Efficient Alkaline Fenton Removal of Three Nitrogen Species (NH3-N, NO3--N, and NO2--N).

The design of high-performance, cost-effective, and durable electrocatalysts for the oxygen reduction reaction (ORR) is essential for the widespread deployment of clean energy technologies, including fuel cells and metal-air batteries. Carbon-based metal-free catalysts (CMFCs) have emerged as promising alternatives to Pt-based materials, with their ORR performance tunable through heteroatom doping and defect engineering. In this study, we report a novel Cl, N-codoped porous carbon catalyst (Cl, N-C) enriched with structural defects, synthesized via a modified metal-organic framework (MOF) strategy. Zinc-1,3,5-benzenetricarboxylate (Zn-BTC) was employed as the MOF precursor, with partial substitution of BTC by pyridine-3,5-dicarboxylate (PDC) to introduce nitrogen and defect sites. During Zn-BTC-PDC pyrolysis, NaCl was added to enable Cl doping and promote further defect formation. Structural characterization reveals that the optimized catalyst (Cl, N-C-2) possesses abundant mesopores, high defect density, and a favorable distribution of pyridinic and graphitic nitrogen species. As a result, Cl, N-C-2 exhibits outstanding ORR activity in alkaline media, achieving a half-wave potential of 0.891 V vs RHE, which ranks among the highest reported to date for CMFCs. Electrochemical analyses demonstrate enhanced electrochemically active surface area, faster kinetics, and excellent durability. In situ ATR-SEIRAS measurements further reveal that Cl doping promotes the formation and stabilization of key OOH intermediates, facilitating a dominant four-electron ORR pathway. When applied as an air cathode in Zn-air batteries, Cl, N-C-2 delivers higher discharge voltage and power density than Pt/C. This work provides an effective strategy for designing high-performance metal-free carbon electrocatalysts through synergistic heteroatom doping and defect engineering.

The combustion efficiency and energy release capacity of solid rocket propellants (SRPs) are predominantly determined by the thermal decomposition behavior of ammonium perchlorate (AP), the core oxidizer. Developing high-efficiency catalysts and deciphering their intrinsic catalytic mechanisms remain a critical challenge. In this work, Ti4+ substitution modulates the distance between Co-Co active sites, triggering a unique intersite distance effect (ISDE) in hierarchical porous Co2TiO4 nanoflower catalysts. Their catalytic performance and intrinsic mechanism for AP thermal decomposition were systematically investigated. The shorter Co-Co active site distance enhances the electronic synergistic effect by enabling a stable "bridged adsorption" dual-site mechanism, potentially breaking the scaling relations between intermediate adsorption energies, and thus significantly improving catalytic performance. This ISDE synergizes with the hierarchical porous structure, optimizing the electronic structure of Co sites (the d-band center shifts 0.3 eV toward the Fermi level), enhancing the adsorption and activation capacity of reaction intermediates, and regulating the NH3 oxidation pathway, increasing the selectivity of NO2 to 48.4%, accompanied by an accelerated decomposition rate and more concentrated exothermic behavior. Density functional theory (DFT) calculations further verify that Ti substitution adjusts the surface electrostatic potential and adsorption energy of reactants, facilitating the cleavage of N-H and Cl-O bonds in NH3 and HClO4, respectively. This work clarifies the critical role of ISDE in mediating catalytic activity and provides a new theoretical paradigm for the rational design of high-performance bimetallic oxide catalysts for energetic material applications, particularly in SRPs.

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.

Self-supported zeolite fibers with multiscale porosity boosting mass transfer and stability for environmental pollutants removal.

Design of FeCoNiSmNd-co-doped porous carbon catalysts from pulverized coal for radical and non-radical peroxymonosulfate activation in organic pollutant degradation

Protonation of pyridinic nitrogen (pyri-N) sites in nitrogen-doped carbon catalysts under acidic conditions converts pyri-N to pyri-NH+, leading to severe catalytic deactivation. Restoring activity requires transforming pyri-NH+ back to pyri-NH, an energetically demanding process that limits oxygen reduction reaction (ORR) efficiency. To overcome this challenge, we developed an N-doped porous carbon catalyst (NpC-7) featuring surface pyri-N active sites and a subsurface graphitic nitrogen (grap-N) layer. The 2D growth of cyanuric acid (CA)-functionalized 2-hydroxyethyl methacrylate (HEMA) polymer within graphene oxide layers ensures uniform N-doping which modulates π-electron and spin states. This engineered architecture delivers ORR activity approaching Pt/C and surpasses conventional nitrogen doped graphene oxide (NrGO) (Eonset = 0.86V, E1/2 = 0.70V vs. 0.76 and 0.61V, respectively). Enhanced performance arises from subsurface grap-N, which donates electron to protonated pyri-NH+, generating an active pyri - NHδ + state that promotes O2 adsorption. In situ electrochemical Raman spectroscopy and density functional theory (DFT) calculations confirm efficient O2 adsorption and intermediate formation, indicating a (2 + 2)e- ORR pathway. These findings highlight the critical role of subsurface grap-N in overcoming acidic deactivation through electronic modulation, offering a blueprint for designing acid-stable carbon electrocatalysts.

A nitrogen-sulfur co-doped porous carbon Zinc-based catalyst for the acetylene hydration

Porous carbon catalyst derived from Co/Cu bimetallic MOFs as PMS activator for efficient degradation of chloramphenicol

Deep co-removal of chlorobenzene and Hg0 from flue gas: CaO-SO2 synergy restores catalytic functionality via a poison-against-poison mechanism.

Hierarchical porous hollow HZSM-5 catalyst for waste plastic upcycling to aromatics oil via synergistic optimization of pore structure and acidic sites

Tri-synergistic design of Pd-Ni/TiO2-Al2O3 porous catalysts for selective and stable hydrogenation of nitrile butadiene rubber

Sulfonic acid functionalized torrefied biocoal facilitates levulinates preparation: Reaction kinetics and process cost analysis

A recyclable 3D porous catalyst derived from waste polyurethane foam: rGO-stabilized Cu-Fe bimetallic composite for bisphenol A removal via adsorption and peroxydisulfate activation

We derive a theoretical model to elucidate the inhibition of catalytic activity during the dehydrogenation of Liquid Organic Hydrogen Carriers (LOHCs). Within our model, we account for the reversible nature of the hydrogenation-dehydrogenation reaction as well as the transport of both LOHC and produced hydrogen. Our analysis reveals that the main limiting factor for the performance of porous catalysts is the transport of dissolved hydrogen, which has been overlooked so far. In particular, we show that two distinct kinetic regimes can arise depending on whether hydrogen leaves the pellet in the form of bubbles or via diffusion. Moreover, we derive the conditions for the onset of bubbling depending on hydrogen supersaturation and capillarity. Beyond LOHC systems, our findings are applicable to a broader class of reversible reactions, particularly those involving volatile products that can leave the liquid reaction medium in the form of bubbles.

While porous catalysts enhance photocatalytic efficiency through improved pollutant adsorption, conventional spectroscopic methods often conflate adsorption equilibria with degradation kinetics. This study pioneers the application of surface-enhanced Raman spectroscopy (SERS) in precisely tracking interfacial molecular transformations during malachite green (MG) degradation on sol-gel solvothermally synthesized TiO2/H3PW12O40 composite catalysts. Dual UV-Vis/SERS analysis revealed critical discrepancies between solution-phase and interfacial processes, enabling a redefinition of the true degradation rate─determined as 60.70% under visible light and 72.56% under UV irradiation. The composite exhibited remarkable performance enhancements: 10× and 5× greater degradation rates than pristine TiO2 under visible (420-800 nm) and UV (λ < 420 nm) irradiation, respectively. The maximum total removal rate of MG was 92.51%. This improvement is attributed to enhanced charge carrier separation efficiency and synergistic Brønsted-Lewis acidity. This work underscores the combined use of UV-Vis and SERS as an indispensable approach for elucidating interfacial mechanisms in advanced photocatalysis.