Enhancing the Catalytic Activity of Mo(110) Surface via Its Alloying with Submonolayer to Multilayer Boron Films and Oxidation of the Alloy: A Case of (CO + O) to CO Conversion.

In-situ formation of boron thin films on the Mo(110) surface, as well as the formation of the molybdenum boride and its oxide and the trends of carbon monoxide catalytic oxidation on the substrates formed, have been studied in an ultra-high vacuum (UHV) by a set of surface-sensitive characterization techniques: Auger and X-ray photoelectron spectroscopy (AES, XPS), low-energy ion scattering (LEIS), reflection-absorption infrared spectroscopy (RAIRS), temperature-programmed desorption (TPD), electron energy loss spectroscopy (EELS) and work function measurements using the Anderson method. The boron deposited at Mo(110) via electron-beam deposition at a substrate temperature of 300 K grows as a 2D layer, at least in submonolayer coverage. Such a film is bound to the Mo(110) via polarized chemisorption bonds, dramatically changing the charge density at the substrate surface manifested by the Mo(110) surface plasmon damping.

Hybrid Metal-Boron Diatomic Site Embedded in C N Monolayer Promotes C-C Coupling in CO Electroreduction.

Double-atom catalyst (DAC) has gained much interest for its versatile tuning and synergistic effect of dual-atom active sites. Metal (M)-metal (M) diatomic sites, either homo- or heteronuclear, are typically researched. Hybrid metal-non-metal combined sites have rarely been studied and even the viability of such active sites are unknown.

Hexagonal and Monoclinic Phases of LaOCO Nanoparticles and Their Phase-Related CO Behavior.

In this study, we prepared hexagonal and monoclinic phases of LaOCO nanoparticles by different wet preparation methods and investigated their phase-related CO behavior through field-emission scanning microscopy, high-resolution transmission electron microscopy, Fourier transform infrared, thermogravimetric analysis, CO-temperature programmed desorption, and linear sweeping voltammetry of CO electrochemical reduction. The monoclinic LaOCO phase was synthesized by a conventional precipitation method via La(OH)CO when the precipitation time was longer than 12 h. In contrast, the hydrothermal method produced only the hexagonal LaOCO phase, irrespective of the hydrothermal reaction time.

Highly improved soot combustion performance over synergetic MnCeO solid solutions within mesoporous nanosheets.

Constructing synergetic bimetal oxide solid solutions with exceptional catalytic performances for efficient soot elimination is becoming a research frontier in environmental catalysis. Herein, synergetic MnCeO solid solutions within mesoporous nanosheets, synthesized by a facile hydrothermal method for the first time, have been performed to catalyze the NO-assisted soot combustion. Research results validate that MnCeO solid solutions displayed highly improved soot combustion performance with respect to activity and selectivity, mainly due to the synergetic effect by combining factors of the unique mesoporous nanosheet-shaped feature, the enhanced chemical nature stemmed from high-valence Mn species, abundant active oxygen species originated from the enriched oxygen vacancies and the escalated redox properties.

Boosting total oxidation of acetone over spinel MCoO (M = Co, Ni, Cu) hollow mesoporous spheres by cation-substituting effect.

Boosting total oxidation of volatile organic compounds (VOCs) over spinel CoO by cation-substituting effect is an effective solution, but the underlying mechanism has not yet been clearly elucidated. Herein, a series of spinel MCoO (M = Co, Ni, Cu) hollow mesoporous spheres (HMS) have been synthesized by solvothermal alcoholysis with goals to elaborate the cation-substituting effect on spinel CoO for total oxidation of VOCs. The physicochemical properties of spinel MCoO (M = Co, Ni, Cu) HMS have been well characterized and correlated with their catalytic activities.

Highly enhanced soot oxidation activity over 3DOM CoO-CeO catalysts by synergistic promoting effect.

Three-dimensionally ordered macroporous (3DOM) CoO-CeO catalysts with controllable Co/Ce molar ratios synthesized by colloidal crystal template method were developed to catalyze the NO-assisted soot oxidation for the first time, and the obtained 3DOM CoO-CeO catalysts exhibited highly enhanced soot oxidation activity. Detailed characterizations of 3DOM CoO-CeO catalysts revealed that the highly enhanced soot oxidation activity was originated from the synergistic promoting effect by combining the macroporous effect resulted from the unique 3DOM framework, the chemical nature associated with more Co reactive sites, the surface enrichment of Ce species and the improved redox properties. Meanwhile, the high NO storage and oxidation capacity resulted from the integrated respective merits of CoO and CeO also accounted for the enhanced soot oxidation activity via NO-assisted mechanism.

CN-graphene supported single-atom catalysts for CO electrochemical reduction reaction: mechanistic insight and catalyst screening.

Single-atom catalysts (SACs) have emerged as an excellent platform for enhancing catalytic performance. Inspired by the recent experimental synthesis of nitrogenated holey 2D graphene (C2N-h2D) (Mahmood et al., Nat.

Low temperature catalytic combustion of propane over Pt-based catalyst with inverse opal microstructure in a microchannel reactor.

A novel Pt-based catalyst with highly regular, periodic inverse opal microstructure was fabricated in a microchannel reactor, and catalytic testing revealed excellent conversion and stable activity for propane combustion at low temperatures.

Adsorption/desorption studies on nanocrystalline alumina surfaces.

Two kinds of nanocrystalline alumina powders, boehmite (gamma-AlOOH, particle size d approximately 10 nm, BET surface area A(BET) = 180-200 m(2) g(-1)) and corundum (alpha-Al(2)O(3), d approximately 400 nm, A(BET) = 7 m(2) g(-1)) were used for comparative investigation by thermogravimetry (TG). The remarkable difference in the dehydration profiles between the two samples gives evidence for a distinct difference in their structures. In the following pyridine adsorption/desorption experiment, gamma-alumina was found to possess much more (20 times) and much stronger acidic sites than corundum.