MOF-derived Co@N-C nanocatalyst for catalytic reduction of 4-nitrophenol to 4-aminophenol.

The Co@N-C nanocatalysts derived by direct carbonization of Co-containing metal organic framework (MOF) structure under N 2 flow have been prepared for their application as catalyst in reducing 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) assisted by NaBH 4 . Under inert gas treatment, we obtained Co 0 phase-based nanocatalyst which inherited their former MOF precursor morphology. The resultant nanocatalysts were denoted as Co@N-C 600, 700, 800 corresponding to the respective carbonization temperatures and each was characterized using powder X-Ray diffraction (PXRD), thermal gravimetric analysis (TGA), scanning electron microscopy (SEM), surface area-porosity and transmission electron microscopy (TEM). We found that Co@N-C 700 presented the desired properties with largest surface area (262.800 m 2 /g), high crystallinity with better Co nanoparticle dispersed on the C-N matrix and sufficient amount of Co per gram of nanocatalyst without obvious particle aggregation. All of the nanocatalysts could catalyze 1.25 mM 4-NP to 4-AP per mg catalyst per second which is comparatively remarkable performance compared to previous reposts. Most importantly, as predicted Co@N-C 700 possessed the highest catalytic activity with 6 times consecutive catalytic reactions in successfully reducing 100% 4-NP to 4-AP. The catalytic activity was speculated due to the Co nanoparticle as catalytic active site worked synergistically with C-N matrix as conductive layer which could provide and transport electrons for catalytic reduction reaction. [ABSTRACT FROM AUTHOR]