Mn-Fe3O4 nanoparticles anchored on the urushiol functionalized 3D-graphene for the electrochemical detection of 4-nitrophenol

Preparation of highly active and cost-effective electrode materials is of great interest in electrochemical detection. In this study, a simple urushiol-templated solvothermal method combined with calcination was proposed to fabricate N-doped three-dimensional graphene (3D-G) with Mn-doped Fe3O4 nanoparticles loaded on the surface (Mn-Fe3O4/3D-G). Because of the large active surface area, porous channel and high loading ratio of Mn-Fe3O4 nanoparticles, as-prepared Mn-Fe3O4/3D-G sensor showed high activity on the determination of 4-nitrophenol (4-NP), which are much improved from the control un-modified samples. The wide linear concentration range (5–100 μM), low detection limit (19 nM) and satisfactory recovery of 4-NP in various water samples (98.38–100.41%) indicated that the Mn-Fe3O4/3D-G electrode can be potentially used for real-world applications. This study gives a simple but meaningful strategy for constructing transition metal oxide/graphene composite materials with high electrocatalytic activity. [Display omitted] •A simple method has been developed to mount Mn-doped Fe3O4 NPs on the three-dimensional graphene (3D-G).•The functionalization of 3D-graphene by urushiol has led to the growth of dense Mn-Fe3O4 NPs.•After calcinations, Mn-Fe3O4/3D-G displays large surface area, high conductivity and excellent electrocatalyst performance.•The constructed sensor shows wide linear range, low detection limit, high sensitivity and good stability in 4-NP detection.