Facilly Prepared Cobalt Nanoparticles Coated In Nitrogen-Doped Carbon Material For Catalytic Hydrogenation Of Nitroarenes

With the development of nanotechnology,nanocatalysts occupy an increasingly important position in the field of heterogeneous catalysis.Cobalt,as a member of transition metals,possesses many excellent natures,such as low cost,relatively low toxicity,greater sustainability and unique reaction characteristic,which makes cobalt-based catalysts attract great attention in the field of heterogeneous catalysis.The design and construction of efficient supported cobalt-based nanocatalysts is a research hotspot in the field of heterogeneous catalysis.Compared with pure carbon materials,nitrogen-doped carbon materials have great advantages in electrical conductivity,surface activity and surface hydrophilicity.As catalyst support,the unique surface chemistry of nitrogen-doped carbon materials can improve the activity,selectivity and stability of supported metal catalysts.Nitrogen-doped carbon supported cobalt nanoparticles catalysts have been developed;its unique and highly efficient catalytic properties have attracted much attention in catalytic hydrogenation.However,the bare cobalt nanoparticles supported catalyst cannot achieve the catalytic efficiency and corrosion resistance of the noble metal,which greatly limits its application and development.In order to further expand the application of nitrogen-doped carbon supported cobalt nanoparticles catalysts in the field of catalysis,nitrogen-doped carbon-coated cobalt nanoparticles catalysts have been developed and studied.This study designed a simple strategy for the preparation of nitrogen-doped carbon-coated cobalt nanoparticles catalysts with cheap precursor materials.The cobalt nanoparticles are uniformly and highly dispersed in the carbon matrix.The nitrogen-carbon shell separates the cobalt nanoparticles spatially,effectively avoiding agglomeration,sintering and loss of cobalt.The strong interaction between the cobalt nanoparticles and the nitrogen-carbon shell causes the surface nitrogen-carbon shell to exhibit metal-like properties.This allows the nitrogen-doped carbon-coated cobalt nanoparticles catalyst to exhibit excellent catalytic activity and stability in the catalytic hydrogenation of nitroarenes.The particular structure of the prepared catalyst contributes significantly to catalyst performance and stability.In the green sustainable and superior efficient catalytic hydrogenation of nitroarenes,a series of nitrogen-doped carbon-coated cobalt nanoparticles catalysts prepared in this study have excellent catalytic performance.(1)In the catalytic transfer hydrogenation of nitroarenes with formic acid as a hydrogen source,the designed Co@NC-600 catalyst effectively overcame the corrosion of cobalt by formic acid.The prepared catalyst exhibited excellent catalytic activity and stability in a base-free system.This work has developed the sustainable catalytic hydrogenation of nitroarenes and expanded the application of cobalt-based catalysts in this field.(2)In addition,we designed and constructed a hierarchic porous yolk-shell-structured nanoreactor,and achieved noble-metal-like catalytic efficiency for catalytic hydrogenation of nitroarenes.The prepared Co@ZDC@mC-700 nanoreactor catalyst in this work greatly improved the catalytic efficiency of cobalt-based catalysts;in the reaction of catalytic hydrogenation of nitroarenes with hydrazine hydrate,the catalytic activity Co@ZDC@mC-700 is almost 50 times that of the similar cobalt-based catalysts.