MnCo2S4 nanoparticle-assembled hierarchical porous sphere as an effective electrocatalyst for highly sensitive and selective nonenzymatic detection of hydrazine

It is highly attractive to design and construct a novel enzyme-free electrode for sensitive and selective detection of hydrazine (N 2 H 4 ). In this paper, for the first time, porous MnCo 2 S 4 sphere was used as an excellent electrocatalyst for N 2 H 4 oxidation, which was synthesized through a facile hydrothermal method. The experiment results revealed that porous MnCo 2 S 4 sphere was constructed from interconnected nanoparticle with a three-dimensional porous structure. Electrochemical measurements demonstrate that the presence of MnCo 2 S 4 reduced the overpotential and accelerated kinetics of N 2 H 4 oxidation. The sensor based on porous MnCo 2 S 4 sphere exhibited an excellent performance for N 2 H 4 analysis with a wide linear range of 0.5   μM–4.78   mM, a high sensitivity of 1495.7   μA   mM −1   cm −2 , a low detection limit of 0.33   μM (S/N   =   3). Moreover, the application of the sensor for detection of N 2 H 4 in tap water samples was demonstrated, which indicates that MnCo 2 S 4 can be employed as the efficient material for electrochemical sensing of N 2 H 4 .