Hydrothermal synthesized urchin-like nickel-cobalt carbonate hollow spheres for sensitive amperometric detection of nitrite

In this article, we present a facile and low-cost method to prepare urchin-like nickel-cobalt carbonate hollow spheres that display excellent electrooxidation of nitrite. The as-fabricated samples are characterized by XRD, SEM, TGA, and BET. The results confirm that the successful formation of nickel carbonate and cobalt carbonate at ratio of 1/2, and their entirely uniform hollow microspherical structure with an average pore size of 4 nm and a pore volume of 0.15 cm(3) g(-1). Moreover, the as-prepared nitrite sensor has a good electrochemical response with the linear range of 5-4000 mu M and the detection limit of 0.002 mu M under optimum conditions, respectively with the correlation coefficient of 0.999. The fabricated nitrite sensor also exhibited high sensitivity and good stability. (C) 2017 Elsevier B.V. All rights reserved.