Chitosan -NH derived efficient CoO catalyst for styrene catalytic oxidation: Simultaneously regulating particle size and Co valence.

In this study, a CoO catalyst is synthesised using the chitosan-assisted sol-gel method, which simultaneously regulates the grain size, Co valence and surface acidity of the catalyst through a chitosan functional group. The complexation of the free -NH complex inhibits particle agglomeration; thus, the average particle size of the catalyst decreases from 82 to 31 nm. Concurrently, Raman spectroscopy, hydrogen temperature-programmed reduction, electron paramagnetic resonance spectroscopy and X-ray photoelectron spectroscopy experiments demonstrate that doping with chitosan N sources effectively modulates Co to promote the formation of oxygen vacancies.

Crystal Plane Effect of CoO on Styrene Catalytic Oxidation: Insights into the Role of Co and Oxygen Mobility at Diverse Temperatures.

In the oxidation reaction of volatile organic compounds catalyzed by metal oxides, distinguishing the role of active metal sites and oxygen mobility at specific preferentially exposed crystal planes and diverse temperatures is challenging. Herein, CoO catalysts with four different preferentially exposed crystal planes [(220), (222), (311), and (422)] and oxygen vacancy formation energies were synthesized and evaluated in styrene complete oxidation. It is demonstrated that the CoO sheet (CoO-I) presents the highest CH catalytic oxidation activity ( = 8.