Enhanced response of sensor on serotonin using nickel-reduced graphene oxide by atomic layer deposition

Atomic layer deposition (ALD) is a promising method for preparing nanomaterials. The thickness and uniformity of nanomaterials can be precisely controlled. Hence, the uniform Ni nanoparticles (Ni NPs) deposited on reduced graphene oxide (rGO) by ALD and got the optimal combination interface. The morphology, structure, and electrochemical behavior of Ni NPs-rGO nanocomposite are investigated. By experiment results, the Ni NPs could occupy some active surface of rGO, resulting in high conductivity and large specific surface area of Ni NPs-rGO nanocomposite. The Ni NPs-rGO nanocomposite exhibits high electrocatalytic activity for serotonin and speeds up the electron transfer between the surface of the electrode and the solution. Therefore, the sensor is prepared by Ni NPs-rGO nanocomposite modified glassy carbon electrode (GCE) and used to sensitive detection of serotonin. By differential pulse voltammetric, the Ni NPs-rGO/GCE enhanced the current responses and showed a wide linear range of 0.02-2 μM with a low detection of 0.01 μM for serotonin (S/N = 3). The Ni NPs-rGO/GCE exhibited good stability, selectivity, and anti-interference ability that can be used for real sample detection. According to these results, the Ni NPs-rGO nanocompositeis successfully prepared by ALD. The properties of Ni NPs-rGO nanocomposite make it an attractive material for potential applications in sensors and catalysis.