Synthesis of δ-MnO via ozonation routine for low temperature formaldehyde removal.

Nowadays, it is still a challenge to prepared high efficiency and low cost formaldehyde (HCHO) removal catalysts in order to tackle the long-living indoor air pollution. Herein, δ-MnO is successfully synthesized by a facile ozonation strategy, where Mn is oxidized by ozone (O) bubble in an alkaline solution. It presents one of the best catalytic properties with a low 100% conversion temperature of 85°C for 50 ppm of HCHO under a GHSV of 48,000 mL/(g·hr).

Highly efficient ozone elimination by metal doped ultra-fine CuO nanoparticles.

Nowadays, ozone contamination becomes dominant in air and thus challenges the research and development of cost-effective catalyst. In this study, metal doped CuO catalysts are synthesized via reduction of Cu by ascorbic acid in base solutions containing doping metal ions. The results show that compared with pure CuO, the Mg and Fe dopants enhance the O removal efficiency while Ni depresses the activity.

Coordination-Controlled Catalytic Activity of Cobalt Oxides for Ozone Decomposition.

Nowadays, it is still elusive and challenging to discover the active sites of cobalt (Co) cations in different coordination structures, though Co-based oxides show their great potency in catalytic ozone elimination for air cleaning. Herein, different Co-based oxides are controllably synthesized including hexagonal wurtzite CoO-W with Co in tetrahedral coordination (Co) and CoAl spinel with dominant Co, cubic rock salt CoO-R with Co in octahedral coordination (Co), MgCo spinel with dominant Co in octahedral coordination (Co), and CoO with mixed Co and Co. The valences are proved by X-ray photoelectron spectroscopy, and the coordinations are verified by X-ray absorption fine structure analysis.

Abatement of dichloromethane with high selectivity over defect-rich MOF-derived Ru/TiO catalysts.

The regulation of oxygen vacancies and Ru species using metal-organic frameworks was synergically adopted in a rational design to upgrade Ru/TiO catalysts, which are highly active for the catalytic oxidation of dichloromethane (DCM) with less undesired byproducts. In this work, Ru/M-TiO and Ru/N-TiO catalysts were synthesized by the pyrolysis of MIL-125 and NH-MIL-125 incorporated with Ru, the existence of Ru nanoclusters and nanoparticles was detected by XAFS, respectively, and the catalytic performance was analyzed comprehensively. Complete oxidation of DCM was obtained at ∼290 °C over Ru/M-TiO and Ru/N-TiO catalysts, while Ru/N-TiO showed quite less monochloromethane (MCM) and higher CO yields, and better dechlorination capacity in oxidation.

Graphene-Modified ZnO Nanostructures for Low-Temperature NO Sensing.

This paper develops a novel ultrasonic spray-assisted solvothermal (USS) method to synthesize wrapped ZnO/reduced graphene oxide (rGO) nanocomposites with a Schottky junction for gas-sensing applications. The as-obtained ZnO/rGO- samples with different graphene oxide (GO) contents ( = 0-1.5 wt %) are characterized by various techniques, and their gas-sensing properties for NO and other VOC gases are also evaluated.