High-sensitivity amperometric hydrazine sensor based on AuNPs decorated with hollow-structured copper molybdenum sulfide nanomaterials

Abstract

Hollow-structured hybrid nanomaterials were superior electrocatalysts on account of their unique structures and preeminent properties. This study showed the synthesis of Au decorated with hollow-structured Cu2MoS4 (H-CMS) nanohybrid via hydrothermal and chemical reduction methods. Furthermore, novel hydrazine (N2H4) electrochemical sensor was fabricated based on the as-prepared nanocomposites. The characterization results revealed that homogeneous AuNPs with an average diameter of 13 nm were anchored on the surface and internal cavity of hollow CMS spheres. In addition, the sensor exhibited some excellent electrochemical performance for N2H4 detection. The linear range obtained by the as-proposed sensor was 0.02–377.7 μM, a much lower detection limit with 7 nM (S/N＝3), and a higher sensitivity with 440.1 μA mM−1 cm−2. The linear range of the sensor was maintained at the same level as the widest or better in some cases compared with the similar type of N2H4 sensors previously reported. At least two orders of magnitude reduced the detection limit of the as-proposed sensor. It was about 21-fold lower than that of the TiO2 @PANI@Au/glassy carbon electrode (GCE) sensor with the lowest detection limit. A factor of 1.5 times improved the sensitivity compared with the analogous type Au-Fe3O4-GO/GCE sensor. Additionally, the Au/H-CMS/GCE sensor displayed fast responses, high selectivity, and superior stability for N2H4 detection.