Synthesis of gold nanoparticles coated on flower-like MoS2 microsphere and their application for electrochemical nitrite sensing

In this work, 3D flower-like MoS 2 microspheres with nanosheets were synthesized by a simple thiourea-assisted hydrothermal route and employed to support gold nanoparticles in order to fabricate a novel nitrite sensor. By this method, stable and well-distributed gold nanoparticles were formed due to the electrostatic attraction between APTES-functionalized MoS 2 and citric-stabilized gold nanoparticles. Electrochemical investigations indicated that Au NPs/MoS 2 nanocomposites exhibited an excellent performance towards nitrite oxidation . Under the optimal experimental condition (pH   6.0), the sensor displayed a wide linear range from 5.0   μM to 27.8   mM with a high sensitivity of 117.0   μAmM −1   cm −2 and a low detection limit of 1.67   μM. In a word, the present study demonstrates that the Au NPs/MoS 2 composites are promising electroactive materials for developing nitrite sensors with great potential.