Investigation On Catalystic Performances Of Co/Fe Bimetallic MOF-based Composite And Its Derivatives

In this study,a Co/Fe bimetallic organic frameworks（Co/Fe-MOFs）were designed and synthesized.After efficiently mixed Co/Fe-MOFs with melamine and NaH₂PO₂,the nitrogenization and phosphorization derivatives were seperately prepared by calcining and pyrolyzing at high temperature,and then used as electrocatalysts for detection of small biomolecules and photocatalyst for degradation of organic pollutants,respectively.Firstly,cobalt and iron nitrate,and 4’,4’’’,4’’’’’-nitrilotris（（[1,1’-biphenyl]-4-carboxylicacid））（H₃NBB）were used as metal coordination precursor and organic ligand,and bimetal Co/Fe-MOF was synthesized by hydrothermal method.A new type of electrocatalyst consisting of N-doped carbon coated bimetal Co-Fe nanoparticles（Co₃O₄/Fe₃O₄/mC@g-C₃N₄）was prepared by calcining the ground mixtures of Co/Fe-MOFs and melamine.The as-prepared Co₃O₄/Fe₃O₄/mC@g-C₃N₄ nanocomposite was used as sensitive layer of electrochemical sensor,and applied for detecting ascorbic acid（AA）,dopamine（DA）,uric acid（UA）and glucose.The detection limits were estimated to be 12.55,0.21,0.18,and 2.53?M,respectively.The constructed electrochemical sensor also exhibited high stability,selectivity and good applicability.Secondly,the Co/Fe-MOFs was phosphatized with NaH₂PO₂ at 300℃to obtain the mesoporous carbon incorporated Co/Fe binary metal phosphide（CoP/Fe₂P@mC）with visible light activity.The CoP/Fe₂P@mC was used as photocatalyst to degrade Rhodamine B（RhB）under visible light.The degradation efficiency of RhB reached 99.7%under visible light for30 min.Moreover,the possible photocatalytic mechanism of CoP/Fe₂P@mC toward RhB degradation was proposed on the basis of radical trapping and electron spin resonance measurements.Therefore,the Co/Fe-MOFs derivatives can be used not only as electrocatalyst for detection of small biomolecules,but also as efficient photocatalyst for degradation of organic pollutants,and possesses potential applications in biodiagnosis,biosensing and environmental monitoring.