Synthetic Pt-Fe(OH) catalysts by one-pot method for CO catalytic oxidation.

Catalytic oxidation is used to control carbon monoxide (CO) emissions from industrial exhaust. In this work, The prepared Pt-Fe(OH) catalysts ( represents the mass fraction of Pt loading (%), a = 0.5, 1 and 2) by the one-pot reduction method exhibited excellent CO catalytic activity, with the Pt-Fe(OH) catalyst, 70% and ∼100% CO conversion was achieved at 30°C and 60°C, respectively.

Unlocking Mixed-Metal Oxides Active Centers via Acidity Regulation for K&SO Poisoning Resistance: Self-Detoxification Mechanism of Zeolite-Confined NO Catalysts.

Selective catalytic reduction of nitrogen oxides (NO) with ammonia (NH-SCR) is an efficient NO reduction strategy, while the denitrification (NO) catalysts suffer from serious deactivation due to the coexistence of multiple poisoning substances, such as alkali metal (e.g., K), SO, .

Assessing health risks from bioaccessible PM-bound toxic metals in Nanchang metro: Implications for metro workers and emissions control.

High concentrations of PM with enriched levels of metallic constituents could significantly affect the health and comfort of metro employees. To avoid overestimating the exposure risks, we investigated the bioaccessibility of toxic metals (TMs) bound in PM from the Nanchang metro using Gamble's solution method, and qualitatively analyzed the impact of valence state and various sources on the bioaccessibility of TMs bound to PM. The results showed that the bioaccessibility of the studied TMs ranged from 2.

Chemical composition, sources, and health risks of PM in small cities with different urbanization during 2020 Chinese Spring Festival.

To investigate the impact of quarantine measures and fireworks banning policy on chemical composition and sources of PM and associated health risks in small, less developed cities, we sampled in Guigang (GG), Shaoyang (SY), and Tianshui (TS), located in eastern, central, and north-western China, in 2020 Spring Festival (CSF). Mass concentration, carbonaceous, metals, and WSIIs of PM were analyzed. The study found high levels of PM pollution with the average concentration of 168.

Revolutionizing Porous Liquids: Stabilization and Structural Engineering Achieved by a Surface Deposition Strategy.

Facile approaches capable of constructing stable and structurally diverse porous liquids (PLs) that can deliver high-performance applications are a long-standing, captivating, and challenging research area that requires significant attention. Herein, a facile surface deposition strategy is demonstrated to afford diverse type III-PLs possessing ultra-stable dispersion, external structure modification, and enhanced performance in gas storage and transformation by leveraging the expeditious and uniform precipitation of selected metal salts. The Ag(I) species-modified zeolite nanosheets are deployed as the porous host to construct type III-PLs with ionic liquids (ILs) containing bromide anion , leading to stable dispersion driven by the formation of AgBr nanoparticles.

Elucidating the role of confinement and shielding effect over zeolite enveloped Ru catalysts for propane low temperature degradation.

Volatile organic compounds (VOCs) are the main precursor for ozone formation and hazardous to human health. Light alkane as one of the typical VOCs is difficult to degrade to CO and HO by catalytic degradation method due to its strong C-H bond. Herein, a series of ultrafine Ru nanoclusters (<0.

DNA-Assisted Creation of a Library of Ultrasmall Multimetal/Metal Oxide Nanoparticles Confined in Silica.

Supported ultrasmall metal/metal oxide nanoparticles (UMNPs) with sizes in the range of 1-5 nm exhibit unique properties in sensing, catalysis, biomedicine, etc. However, the metal-support and metal-metal precursor interactions were not as well controlled to stabilize the metal nanoparticles on/in the supports. Herein, DNA is chosen as a template and a ligand for the silica-supported UMNPs, taking full use of its binding ability to metal ions via either electrostatic or coordination interactions.

Intra-crystalline mesoporous zeolite encapsulation-derived thermally robust metal nanocatalyst in deep oxidation of light alkanes.

Zeolite-confined metal nanoparticles (NPs) have attracted much attention owing to their superior sintering resistance and broad applications for thermal and environmental catalytic reactions. However, the pore size of the conventional zeolites is usually below 2 nm, and reactants are easily blocked to access the active sites. Herein, a facile in situ mesoporogen-free strategy is developed to design and synthesize palladium (Pd) NPs enveloped in a single-crystalline zeolite (silicalite-1, S-1) with intra-mesopores (termed Pd@IM-S-1).

Environmental benign synthesis of Nano-SSZ-13 via FAU trans-crystallization: Enhanced NH-SCR performance on Cu-SSZ-13 with nano-size effect.

Small pore zeolites with chabazite structure have been commercialized for selective catalytic reduction (SCR) of nitrogen oxides (NO) with ammonium (NH) from diesel exhaust. However, conventional zeolite synthesis processes detrimental effects on the environment due to the consumption of large amount of water, organic templates. Thus, this study proposed a green synthesis process with addition of minimal amount of water, structure directing agent and shortened steps to prepare nano-sized SSZ-13 (0.

Novel shielding and synergy effects of Mn-Ce oxides confined in mesoporous zeolite for low temperature selective catalytic reduction of NO with enhanced SO/HO tolerance.

Nitrogen oxides (NO) are a primary source of air pollutants from combustion of fossil fuels. Though Mn-Ce based catalysts exhibit superior low temperature activities, their water and SO tolerance is inferior to other metal oxide catalysts, due to their strong water adsorption and sulfate species formation tendency at low reaction temperatures. Herein, a confinement strategy was adopted to design and synthesize a novel Mn-Ce based catalyst for selective catalytic reduction of NO with NH.

One-pot synthesis of layered mesoporous ZSM-5 plus Cu ion-exchange: Enhanced NH-SCR performance on Cu-ZSM-5 with hierarchical pore structures.

Hierarchical ZSM-5 zeolite with meso- and micro-pore structures was successfully prepared through a facile one-pot hydrothermal synthesis method using bifunctional template. After copper ion-exchange, it was applied for the selective catalytic reduction of NO with NH (NH-SCR). Compared with conventional Cu-ZSM-5 catalyst containing only micropores, the hierarchical catalyst with ca.

Confined Ultrathin Pd-Ce Nanowires with Outstanding Moisture and SO Tolerance in Methane Combustion.

An efficient strategy (enhanced metal oxide interaction and core-shell confinement to inhibit the sintering of noble metal) is presented confined ultrathin Pd-CeO nanowire (2.4 nm) catalysts for methane combustion, which enable CH total oxidation at a low temperature of 350 °C, much lower than that of a commercial Pd/Al O catalyst (425 °C). Importantly, unexpected stability was observed even under harsh conditions (800 °C, water vapor, and SO ), owing to the confinement and shielding effect of the porous silica shell together with the promotion of CeO .

Mesoporous MFI Zeolite with a 2D Square Structure Directed by Surfactants with an Azobenzene Tail Group.

Mesoporous MFI zeolites (MMZs) have been constructed by using the surfactant-containing azobenzene segment in the hydrophobic tail. The cylindrical π-π stacking of azeobenzene groups is considered to be the key factor to form the ordered mesostructure through cooperative structural matching and the rearrangement of MFI frameworks. The mesostructure has been tuned from a disordered hierarchical arrangement into an ordered 2D square p4mm structure by changing the length of the alkyl chain between the diquaternary ammonium head group and azobenzene group.

In Situ Embedded Pseudo Pd-Sn Solid Solution in Micropores Silica with Remarkable Catalytic Performance for CO and Propane Oxidation.

Most of the industrial and environmental catalytic reactions are operated at high temperature for a long time, and the sintering of the active centers is the main factor leading to catalysts deactivation, especially for noble metal catalysts. Herein we develop a dual confinement (enhanced metal-oxide interaction and the porous shell confinement) strategy to prepare Pd-Sn pseudo solid solution and in situ embedded in microporous silica for the first time and showed superior catalytic performance for CO and propane total oxidation (two main vehicle emission gases), even stored more than 640 days.

Modifying the Surface of γ-Al O with Y Sn O Pyrochlore: Monolayer Dispersion Behaviour of Composite Oxides.

To investigate the dispersion behaviour of composite oxides on supports, and to obtain better supports for Pd for CO oxidation, a series of Y Sn O /Al O composite oxides with different Y Sn O loadings were prepared by a deposition-precipitation method. XRD and X-ray photoelectron spectroscopic extrapolation methods revealed that, similar to single-component metal oxides, composite oxides can also disperse spontaneously on support surfaces to form a monolayer with a certain capacity. The monolayer dispersion capacity/threshold for Y Sn O on the surface of γ-Al O is 0.

O2 adsorption on MO2 (M=Ru, Ir, Sn) films supported on rutile TiO2(110) by DFT calculations: Probing the nature of metal oxide-support interaction.

To explore metal oxide-support interaction and its effect on O2 adsorption, periodic DFT calculations were used to explore the most preferred O2 molecular and dissociative adsorption on stoichiometric (MO2) and defective (MO2-x) (M=Ru, Ir, Sn) films supported on rutile TiO2(110), and compared with that on pure surfaces without TiO2(110) support. For defective RuO2-x films, it is revealed that the TiO2(110) support and the film thickness have an evident impact on the O2 adsorbed species. On the contrary, the two factors show little influence for defective IrO2-x and SnO2-x films.

One-pot synthesis of benzamide over a robust tandem catalyst based on center radially fibrous silica encapsulated TS-1.

A center radially fibrous silica encapsulated TS-1 zeolite (TS-1@KCC-1) has been synthesized in a microemulsion system for the first time. Supporting the Rh(OH)3 species, this novel core-shell structured material serves as a robust bifunctional catalyst for one-pot synthesis of benzamide from benzaldehyde, ammonia and hydrogen peroxide, in which the aldehyde ammoximation and oxime rearrangement occur in a tandem way.