Synthesis of palladium@gold nanoalloys/nitrogen and sulphur-functionalized multiple graphene aerogel for electrochemical detection of dopamine

•We reported Pd@A/nitrogen and sulphur-functionalized multiple graphene aerogel.•The nanohybrid offers unique three-dimensional architecture with rich of mesopores.•The architecture achieve to ultrahigh electron/ion transfer and electrocatalytic activity.•The sensor exhibits an ultrasensitive electrochemical response towards dopamine.•The study provides promising approach for the fabrication of graphene-metal hybrids.

Integration of noble metal nanomaterials on graphene nanosheets potentially paves one way to improve their electronic, chemical and electrochemical properties. The study reported synthesis of palladium@gold nanoalloys/nitrogen and sulphur-functionalized multiple graphene aerogel composite (Pd@Au/N,S-MGA). The as-prepared composite offers a well-defined three-dimensional architecture with rich of mesopores. The Pd@Au nanoalloys were dispersed on the graphene framework networks and their active sites were fully exposed. The unique structure achieves to ultra high electron/ion conductivity, electrocatalytic activity and structural stability. The sensor based on the Pd@Au/N,S-MGA creates ultrasensitive electrochemical response towards dopamine due to significantly electrochemical synergy between Pd, Au and N,S-MGA. Its differential pulse voltammetric signal linearly increases with the increase of dopamine concentration in the range from 1.0 × 10−9 M to 4.0 × 10−5 M with the detection limit of 3.6 × 10−10 M (S/N = 3). The analytical method provides the advantage of sensitivity, reproducibility, rapidity and long-term stability. It has been successfully applied in the detection of trace dopamine in biological samples. The study also opens a window on the electronic properties of graphene aerogel and metal nanomaterials as well their nanohybrids to meet needs of further applications as nanoelectronics in diagnosis, bioanalysis and catalysis.

Graphical abstractWe reported a new palladium@gold nanoalloys/nitrogen and sulphur-functionalized multiple graphene aerogel. The sensor based on the nanohybrid exhibits ultrahigh sensitivity, reproducibility and stability to electrochemical detection of dopamine.Download high-res image (198KB)Download full-size image