Abstract
Combustion catalysts have been extensively explored to reduce the emission of hydrocarbons that are capable of triggering photochemical smog and greenhouse effect. Palladium as the most active material is widely applied in exhaust catalytic converter and combustion units, but its high capital cost stimulates the tremendous research on non-noble metal candidates. Here we fabricate highly defective cobalt oxide nanocrystals via a controllable oxidation of carbon-encapsulated cobalt nanoparticles. Strain gradients induced in the nanoconfined carbon shell result in the formation of a large number of active sites featuring a considerable catalytic activity for the combustion of a variety of hydrocarbons (methane, propane and substituted benzenes). For methane combustion, the catalyst displays a unique activity being comparable or even superior to the palladium ones.
Highlights
Combustion catalysts have been extensively explored to reduce the emission of hydrocarbons that are capable of triggering photochemical smog and greenhouse effect
Palladium (Pd) is the most active metal for catalytic combustion of hydrocarbons, while polyvalent metal oxides, especially cobalt oxide (Co3O4), as the promising candidates still cannot provide a satisfactory activity at the low-temperature region[1,2]
Using the carbon-encapsulated Co (Co@C) core–shell nanocapsules as the starting materials, it should be feasible to produce Co3O4 nanocrystals with a highly defective surface that may display a satisfactory activity for hydrocarbon combustion reaction
Summary
Combustion catalysts have been extensively explored to reduce the emission of hydrocarbons that are capable of triggering photochemical smog and greenhouse effect. Strain gradients induced in the nanoconfined carbon shell result in the formation of a large number of active sites featuring a considerable catalytic activity for the combustion of a variety of hydrocarbons (methane, propane and substituted benzenes). The atomic diffusion of matter is balanced by an opposite flow of vacancies that are capable to condense into pores and result in deformation or void formation In case this process is confined into a nano-sized core, both the high surface-to-volume ratio of the particle and the absence of defects in the core remarkably enhance the rate of vacancy injection. Using the Co@C core–shell nanocapsules as the starting materials, it should be feasible to produce Co3O4 nanocrystals with a highly defective surface that may display a satisfactory activity for hydrocarbon combustion reaction. Our studies suggest that the strain gradients induced in the nanoconfined graphitic shell are beneficial to generate abundant active sites for enhancing catalytic activity and to prevent the severe aggregation of metal nanoparticles for keeping stability
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
