Bifunctional hexagonal Ni/NiO nanostructures: influence of the core–shell phase on magnetism, electrochemical sensing of serotonin, and catalytic reduction of 4-nitrophenol. Issue 4 (18th February 2019)

• Record Type: Journal Article
• Authors: Manigandan, R.; Dhanasekaran, T.; Padmanaban, A.; Giribabu, K.; Suresh, R.; Narayanan, V.
• Is Part Of: Nanoscale advances. Volume 1:Issue 4(2019)
• Page Start: 1531
• Page End: 1540
• Publication Date: 2019-02-18
• Subjects: 620.5
• DOI: 10.1039/c8na00342d
• Languages: English
• ISSNs: 2516-0230

Abstract

Abstract : Ni 0 /NiO (nickel/nickel oxide) core–shell nanostructures were synthesized through a facile combustible redox reaction. Abstract : Ni 0 /NiO (nickel/nickel oxide) core–shell nanostructures were synthesized through a facile combustible redox reaction. Remarkably, the hetero-phase boundary with different crystalline orientations offered dual properties, which helped in bifunctional catalysis. Presence of a metallic Ni phase changed physicochemical properties and some emerging applications (magnetic properties, optical conductivity, electrochemical sensitivity, catalytic behaviour) could be foreseen. Moreover, formation of a NiO layer on metal surface prevented magnetism-induced aggregation, arrested further oxidation by hindering oxygen diffusion, and acted as a good sorbent to enhance the surface adsorption of the analyte. Hexagonal Ni/NiO nanostructures manifested well-defined ferromagnetic behavior and the catalyst could be collected easily at the end of the catalytic reduction. Ni/NiO core–shell catalysts at the nanoscale had outstanding catalytic performance (reduction of 4-nitrophenol to 4-aminophenol) compared with pure NiO catalysts beyond a reaction time of ∼9 min. The estimated sensitivity, limit of detection and limit of quantification towards the electrochemical sensing of serotonin were 0.185, 0.43 and 1.47 μM μA −1, respectively. These results suggest that a bifunctional Ni/NiO nanostructure could be a suitable catalyst for electrochemical detection of serotonin and reduction of 4-nitrophenol.