A novel acid pretreatment strategy modulates the distribution of silanol groups on MCM-41 by increasing isolated silanol groups while reducing H-bonded ones, which enables the formation of highly dispersed Ag nanoparticles. The resulting Ag catalyst dramatically enhances the catalytic performance, achieving complete formaldehyde conversion at 75 °C, with an approximately 50-fold enhancement compared to untreated samples (4.45 nm, 100%, vs. 15.4 nm, 2%).

Selective catalytic oxidation of ammonia (NH3-SCO) over transition metal oxide catalysts with high NH3 conversion and N2 selectivity at low temperatures is important but remains a significant challenge. Herein, we propose a novel strategy for depositing phosphate (PO x ) onto CeO2 nanorods, and PO x acts as a host for CoO x (CoO x -P0.05/CeO2). The CoO x -P0.05/CeO2 enables an NH3 conversion of 84% and a N2 selectivity of 86% at a low temperature of 200 degrees C, obviously outperforming CoO x /CeO2 (N2 selectivity of 40%) and P0.05/CeO2 (NH3 conversion of 7% even at 250 degrees C). The strong interaction of CoO x with PO x strengthens the Co-O bond and generates medium-strong acid sites, which are found to play an important role in improving N2 selectivity. Density functional theory (DFT) calculations and in situ diffuse reflectance infrared Fourier transform spectra (in situ DRIFTS) reveal that the introduction of PO x enhances the binding energy with NH3 and significantly alters the bidentate nitrate of CoO x /CeO2 to monodentate nitrate of CoO x -P0.05/CeO2, thereby substantially suppressing the formation of byproducts N2O and NO and enhancing N2 selectivity.

Designing high-performance catalysts for efficient HCHO oxidation under mild conditions is essential, yet remains challenging to achieve through conventional experimental screening. Here, we present a machine-learning-accelerated strategy for designing novel oxide-Ag tandem systems that overcome this limitation by coupling oxide-mediated HCHO activation with subsequent intermediate oxidation on Ag. Guided by an adsorption-energy-based activity descriptor, four theoretically predicted oxide-Ag systems (TiO2, Nb2O5, Ga2O3, SnO2) exhibit markedly enhanced tandem catalytic performance compared to conventional Ag catalysts. In particular, a representative TiO2/Ag-γ-Al2O3, prepared by simple physical mixing of commercial anatase and Ag-γ-Al2O3 catalyst, achieves an HCHO oxidation rate of 0.56 μmol gAg-1 s-1 at 55 °C, surpassing Ag-γ-Al2O3 alone by over 2 orders of magnitude in performance. Combining experimental and theoretical studies further reveals a cascade reaction mechanism, in which TiO2 catalyzes the HCHO-to-methyl formate transformation via a surface OH-mediated pathway, followed by efficient methyl formate oxidation to CO2 on Ag-γ-Al2O3. Particularly, the local oxygen environment over oxide surfaces is identified as a key factor governing HCHO adsorption and conversion. This work establishes a generalizable design principle for tandem catalysts and provides a data-driven framework for advancing low-temperature HCHO oxidation technologies.

Cuprous oxide (Cu2O) is a pivotal candidate for the electrocatalytic reduction of CO2 to multi‑carbon (C2+) products. However, it suffers from limited selectivity and structural instability due to severe surface reconstruction. Herein, an integrated strategy of interfacial engineering and doping was proposed to systematically modulate the electronic interactions between La and Cu, thereby uncovering its decisive role in dictating C2+ selectivity. In situ spectroscopic and electrochemical analyses revealed a striking structure-activity relationship. Strong electronic interactions significantly enhanced the coverage of atop-bonded CO (*COatop). This optimized electronic environment intrinsically accelerated CC coupling and effectively circumvented the inactive bridge-bonded (*CObridge) reconstruction trap, which could drive the rapid formation of the critical *HOCCOH intermediate. Furthermore, the doping of La into the Cu2O lattice effectively directed the *H species from water dissociation toward the hydrogenation of C2+ products, thereby avoiding the hydrogen evolution reaction (HER). Consequently, the optimized catalyst achieved a maximum C2+ Faradaic efficiency (FE) of 71.1% (with FEH2 of only 14.6%) at −0.94 V vs. RHE under a high current density of 650 mA cm−2. Notably, the protective role of La(OH)3 effectively stabilized the active Cu+ species against reduction, enabling stable operation for 900 min at industrial-relevant current densities.

Selective catalytic oxidation of ammonia (NH3-SCO) over transition metal oxide catalysts with high NH3 conversion and N2 selectivity at low temperatures is important but remains a significant challenge. Herein, we propose a novel strategy for depositing phosphate (POx) onto CeO2 nanorods, and POx acts as a host for CoOx (CoOx-P0.05/CeO2). The CoOx-P0.05/CeO2 enables an NH3 conversion of 84% and a N2 selectivity of 86% at a low temperature of 200 °C, obviously outperforming CoOx/CeO2 (N2 selectivity of 40%) and P0.05/CeO2 (NH3 conversion of 7% even at 250 °C). The strong interaction of CoOx with POx strengthens the Co-O bond and generates medium-strong acid sites, which are found to play an important role in improving N2 selectivity. Density functional theory (DFT) calculations and in situ diffuse reflectance infrared Fourier transform spectra (in situ DRIFTS) reveal that the introduction of POx enhances the binding energy with NH3 and significantly alters the bidentate nitrate of CoOx/CeO2 to monodentate nitrate of CoOx-P0.05/CeO2, thereby substantially suppressing the formation of byproducts N2O and NO and enhancing N2 selectivity.

Cr doping distorts the Fe 2 (MoO 4 ) 3 lattice and modulates electronic states, concurrently lowering E a and extending the NH 3 -SCR operating window.

The development of Au-based catalysts for volatile organic compound (VOC) oxidation holds significant promise for improving air quality. In this study, we introduce a novel strategy to fabricate stable and highly dispersed metal Au nanoparticles (Au0 NPs) by constructing an Au@C nanostructure via in situ organic C-doping with H2 pretreatment, followed by oxidative removal of carbon shell. This Au@C nanostructure is essential for achieving well-dispersed, ultra-small Au NPs on MCM-41 support, reducing their average size from 4.6 nm to 2.5 nm, due to the spatial confinement and electronic interaction provided by the in situ formed carbon layer, which together suppress particle migration and sintering. The resulting Au NPs enhance HCHO activation, facilitating the formation of the active dioxymethylene (DOM) and formate intermediates, while also improving O2 activation. The designed Au/MCM-41 catalyst (Au/M41-HA) achieves HCHO complete conversion at room temperature, exhibiting 2.36 times higher activity than conventional Au/M41-A catalyst with larger Au NPs. Thus, this work not only presents an effective catalyst for HCHO elimination, but also offer a new strategy for the rational design of highly dispersed and small-sized noble metal particles supported on silica materials.

The development of SCR catalysts with low-temperature activity and high SO2/H2O tolerance remains urgent for industrial flue gas treatment. In this paper, activated carbon was used as the support. A series of efficient low-temperature NH3-SCR catalysts were synthesized by combining S, N doping and bimetallic modification. Several characterization techniques, including XRD, BET, XPS, and TPD, were used. These tools helped to systematically explore the relationship between catalyst structure and activity. The results demonstrated that the Mn1Ce4/SN2.5 catalyst achieved a NOx conversion rate of up to 98 % within the temperature range of 200-260 degrees C, and exhibited excellent SO2 and H2O tolerance, along with outstanding stability. Analysis was performed based on the principles of density functional theory (DFT). Theoretical analysis revealed that S, N co-doping creates an optimal electronic environment. This occurs through three main mechanisms. First, it enhances electron transfer, showing a 150 % increase. Second, it strengthens orbital hybridization, with a 74 % enhancement. Third, it optimizes charge redistribution, achieving a 2.3-fold increase in accumulation. Additionally, a strong Mn4 + /Ce3+ synergistic effect was observed. Mulliken charge analysis indicated a reduction in the charge of the Mn active center (+1.85e-* +1.58e). Bond length optimization analysis revealed a shortened Mn-NO distance (2.18 & Aring;-* 1.95 & Aring;), a 74 % enhancement in the orbital overlap integral, and a 150 % increase in electron transfer quantity. Theoretical predictions were consistent with experimental observations, confirming the synergistic enhancement mechanism of S, N co-doping. The superior performance is attributed to several factors. These include abundant acid sites and a high Mn4+/Ce3+ oxidation state ratio. In addition, S, N doping enhances the concentration of oxygen vacancies and surface-adsorbed oxygen. These features collectively promote the "Fast SCR" reaction pathway.

Volatile Organic Compounds (VOCs) are key contributors to photochemical smog and various diseases, posing serious threats to the environment and human health. Catalytic oxidation is an efficient and ideal technology for the VOCs removal, with the catalyst performance directly determining the removal efficiency. As research on catalysts progresses, in addition to low-temperature activity, the thermal stability of a catalyst has also become a critical element for evaluating catalytic performance. A catalyst with high thermal stability can effectively delay sintering during reactions and has a longer service life.However, there is a lack of detailed reviews on the application of highly thermally stable catalysts for VOCs oxidation. This paper systematically introduces the latest advancements in highly thermally stable catalysts for VOCs treatment to fill this gap. Specifically, we elucidate the fundamental principles of the catalyst sintering process. Subsequently, the design and rational preparation strategies of highly thermally stable catalysts are highlighted, and advanced characterization techniques used to study the sintering process of catalysts are discussed. Finally, this paper demonstrates the success of highly thermally stable catalysts in the catalytic oxidation of VOCs. Moreover, the technical challenges and future prospects in this field are forecasted. The insights provided in this review could be instrumental in guiding the controllable synthesis of highly thermally stable VOCs catalysts and enhancing the understanding of the sintering mechanisms.

ABSTRACT Tandem catalytic systems for HCHO oxidation are generally regarded as a relay process comprising intermediate (e.g., Methyl formate, MF) generation on zeolites and subsequent intermediates‐to‐CO 2 conversion on supported metal catalysts. Here, a new cascade pathway mediated by the secondary intermediate methanol (CH 3 OH) over ZSM‐5/Pt‐γ‐Al 2 O 3 tandem catalyst is proposed, which is composed of physically mixed ZSM‐5 and Pt‐γ‐Al 2 O 3 with an overall Pt content of only 0.3 wt%. In this system, the CH 3 OH is generated directly via MF decomposition on acidic ZSM‐5 and subsequently serves as the primary active intermediate on Pt‐γ‐Al 2 O 3 catalyst, enabling efficient HCHO‐to‐CO 2 complete conversion under ambient conditions. The deep studies with Pd‐ and Ag‐based tandem systems further reveal that the reaction pathway is steered by the intrinsic reactivity of intermediates on supported metal catalysts: CH 3 OH‐mediated cascade routes dominate in Pt‐ and Pd‐containing systems, whereas MF remains the sole reactive intermediate over Ag‐based tandem catalysts. Additionally, we demonstrate that the molecular diffusion of key intermediate within ZSM‐5 plays a decisive role in proximity‐dependent catalytic behavior. Specifically, the strong adsorption affinity and interfacial accumulation of CH 3 OH on ZSM‐5 necessitate close spatial proximity between the zeolite and Pt catalyst, in contrast to the weaker adsorption affinity of MF.

Developing highly efficient, stable, and economical catalysts is crucial for the catalytic oxidation of toluene. Herein, Ce was successfully doped into the lattice of the LaCoO3 perovskite, and the Ce substitution significantly promoted the catalytic performance of the lanthanum-cobalt perovskite for toluene oxidation. La0.95Ce0.05CoO3 catalyst demonstrated the optimal catalytic activity, achieving a toluene conversion of 90% at 208 degrees C, which was 35 degrees C lower than that of LaCoO3. La0.95Ce0.05CoO3 maintained excellent stability during extended reaction (1200 min) and exhibited good water resistance. Ce substitution led to an increase in the relative content of surface Co3+ species, leading to a higher number of active sites on the catalyst surface. Furthermore, it was found that Ce substitution also enhanced the mobility of lattice oxygen in perovskite. The types of intermediate species remained unchanged, however, the formation and consumption rates were significantly accelerated by Ce substitution. These findings provided new insights into how Ce substitution promoted the catalytic performance of LaCoO3 and contributed to the development of catalysts for toluene oxidation.

Spent catalysts contain significant Platinum (Pt) secondary resources. Photochemical methods represent a promising green strategy for recovering Pt from spent catalysts, however achieving efficient recovery remains challenging. Herein, a synergistic photochemical system composed of Fe(III)-oxalate complexes (FOC), NaCl, and sodium persulfate (NaPS) for the highly efficient oxidative dissolution of Pt is reported. This system achieved complete dissolution (100%) of Pt from spent powder catalysts and was successfully extended to hydrophobic membrane electrode assembly (MEA) catalysts combined with the solvent pretreatment. A relatively stable Pt dissolution efficiency (>95%) was still maintained in this system even in the presence of coexisting impurity cations (Cu2+, Ni2+, Zn2+ and Al3+). Pt dissolution followed an oxidation-coordination pathway, primarily driven by ·OH radicals (63.4% contribution) and SO4·− radicals (29.4% contribution). The Fe(III)/Fe(II) cycling was identified as the core of superior performance for the FOC-NaCl-NaPS system. The initial generation of Fe(II) via FOC photolysis triggered the NaPS activation to form SO4·− radicals, and meanwhile resulted in the regeneration of Fe(III)-oxalate complexes. The continuous Fe(III)/Fe(II) cycling and the dual-activation of NaPS (direct photoactivation and Fe(II)-mediated activation thereby facilitated Pt dissolution efficiency. Overall, these findings provide new insights into the development of advanced photochemical systems for the sustainable recovery of precious metals.

Industrial catalysts and electronic waste (e-waste) contain significant amounts of gold (Au), representing the crucial secondary resources. The key research challenge lies in achieving green and efficient Au recovery while avoiding the use of highly toxic and corrosive reagents in traditional methods. In this work, a cyanidation-like photochemical recovery system composed of Fe(III) oxalate complexes (FOC), acetonitrile (MeCN) and H2O2 has been developed. Nearly 100 % dissolution of Au from spent catalysts is achieved at room temperature under xenon lamp irradiation for 4 h. center dot OH and center dot CN radicals synergistically participate in the dissolution process of Au. H2O2 can promote the generation of center dot OH radicals, which enhance the oxidative capacity. And the center dot CN radicals can coordinate with Au to form stable complexes. The combined action of oxidation by center dot OH radicals and coordination by center dot CN radicals facilitates the dissolution of Au. The dissolution efficiency of Au from e-waste could achieve 100 % under both xenon lamp irradiation for 16 h and solar irradiation for 7 days. High-purity Au (99.05 %) was subsequently recovered via electrolysis. Overall, this photochemical recovery system combines environmental friendliness with economic potential, offering a novel approach for the sustainable reclamation of Au resources.

A novel FOC-T system accelerates the photochemical dissolution of gold, platinum, and palladium from wastes via an environmentally friendly route.

Bifunctional zeolite-Ag catalysts with a tandem process offer a versatile pathway for efficient HCHO removal at low temperature. The overall performance of tandem systems is highly sensitive to the tunable nature of the Ag component. Herein, we report a tandem ZSM-5||Ag/gamma-Al2O3 catalyst that exhibits superior low-temperature activity compared to the ZSM-5||Ag/SiO2 catalyst, achieving 100% conversion at 55 degrees C versus 32% for the latter. This dramatic improvement is attributed to the morphological variations induced by differences in the mobility and dispersion of supported Ag nanoparticles. This process involves a complex interplay between the properties of metal nanoparticles (NPs) and the supports. Combining experiments and advanced ab initio molecular dynamics simulations (AIMD), the control of Ag NPs growth behaviors by regulating metal-support interaction (MSI) strength and surface diffusion on different supports is revealed. Strong MSI and high diffusion barrier on gamma-Al2O3 triggers the slow Ostwald ripening (OR), whereas weak MSI and low diffusion barrier on SiO2 stimulates the facile particle migration and coalescence (PMC), leading to rapid activity decay. The observed activity difference is strongly related to the surface activation of MF intermediates and the O2 molecule, which was controlled by Ag NPs size. These findings demonstrate the feasibility and efficacy of controlling MSI strength for the design of stable and high-performance supported metal catalysts.

Green selective metallurgy of precious metals (PMs) from industrial multimetal wastes is attracting more attention. Herein, a tandem dissolution strategy of Fe(III) oxalate complex (FOC)-halogen (I/Br) sequential system was put forward. FOC-I system was crucial for selective recovery, which was suitable for Pt dissolution but passivation for Pd recovery, while FOC-Br system was universal for platinum group metals (PGMs) dissolution. Pt and Pd could be selectively and completely recovered from spent multi-PMs containing cordierite powder catalysts. 92.26% Pt and 94.73% Pd were selectively separated from spent unbroken monolithic cordierite catalysts. And 99.62% Au and 95.50% Pd could also be recovered from unbroken e-wastes, respectively. Oxygen radicals played a crucial role in the generation and migration of halogen reactive species such as I (Br)•, I (Br)2, and I (Br)3 -. The method for the dissolution of halogen oxidation-coordination in FOC-I/FOC-Br systems was proposed. The recovered Pt/Pd-containing lixivium has been demonstrated to be a suitable precursor solution for the preparation of monolithic honeycomb catalysts used in air purification. The photochemical tandem dissolution in the sequential FOC-I/FOC-Br system will pave a way for the development of green metallurgy.

An interzeolite conversion (IZC) method was developed for the rapid synthesis of Cu-SAPO-34 from SAPO-37, achieving isolated Si distribution and optimized Cu states. The resulting Cu-SAPO-34 exhibited exceptional NH3-SCR performance, with over 90% NO conversion from 200-600 degrees C due to proper acidity and Cu status generated from the isolated Si.

The inactive and unstable active sites limit the development of the electrochemical CO2 reduction reaction (CO2RR) under a large current density. Herein, nitrogen-doped In2O3 was designed, which achieved a formate Faradaic efficiency (FEformate) of 97.6% with a formate partial current density (jformate) of 390.6 mA cm-2. Moreover, it maintained an FEformate above 90% for over 20 h at 200 mA cm-2 in a flow cell, while pristine In2O3 lost CO2RR activity within 4 h. It was found that nitrogen doping induced the electrons to transfer from the catalyst to the reactant molecules more easily and quickly to avoid the corrosion of the catalyst caused by electron accumulation. Meanwhile, the nitrogen dopant favored the adsorption of *CO2- intermediates in the form of the OC*O*- adsorption mode and promoted the formation of formate-related *CO2- and *OCHO intermediates at lower potentials, thus facilitating formate production. This fundamental insight aids in the development of highly active catalysts with ultrastability under a large current density.

The hemodialysis membrane is crucial for maintaining the lives of patients with end-stage renal disease. However, during use, the membrane is prone to issues such as clotting and oxidative stress. Of particular concern is the relatively low removal efficiency of the most destructive reactive oxygen species, the hydroxyl radical (center dot OH). In this study, the in situ growth of Prussian blue nanoperoxidase on polysulfone membranes was used to enhance the anticoagulation and antioxidant performance of the membranes. These functionalized membranes demonstrated clearance capacity of 54%, 77%, and 52% for 1,1-diphenyl-2-trinitrophenylhydrazine radicals, 2,2'azinobis(3-ethylbenzothiazoline-6-sulfonic acid ammonium salt), and hydrogen peroxide, respectively. Specifically, the clearance capacity for center dot OH was 83% (2.82 mu mol/cm2), which is the second highest value reported for membranes. Furthermore, the activated partial thromboplastin time reached 95 s. The antioxidant properties of the modified membrane remained stable after 12 h of cleaning.

The ring-opening of epoxides plays a crucial role in synthesizing antitumoral pharmaceuticals and fine chemicals, and the key lies in the rational design of highly efficient catalysts. Herein, by using 4-(2-carboxyethenyl)benzoic acid and 1,10-phenanthroline (phen) hydrate as mixed ligands, a new Co(II)-based porous metal-organic framework (Co-CBA) has been synthesized via a solvothermal reaction. Structural analysis revealed that Co-CBA features unique trinuclear clusters as building blocks, which link with the ligands to form a sequentially porous two-dimensional network. The appropriate pore channels and high density of metal active clusters in Co-CBA facilitate its exceptional catalytic performance as a heterogeneous catalyst in the ring-opening reaction of epoxy chloropropane with methanol. Under optimal conditions, this catalyst achieves >99% conversion and >99% selectivity for the target product 1-chloro-3-methoxypropan-2-ol within 28 h. In addition, Co-CBA also displays excellent substrate compatibility, outstanding reusability, and robust structural stability after the catalysis. A plausible reaction pathway for the ring-opening of epoxides has also been proposed.