Comparison of NiS2 and α-NiS hollow spheres for supercapacitors, non-enzymatic glucose sensors and water treatment

• Published in: Dalton transactions : an international journal of inorganic chemistry 2015-10, Vol.44 (39), p.17278-17285
• Main Authors: Wei, Chengzhen, Cheng, Cheng, Cheng, Yanyan, Wang, Yan, Xu, Yazhou, Du, Weimin, Pang, Huan
• Format: Article
• Language: English
• Subjects: Electric Capacitance; Electrochemical Techniques - methods; Glucose - analysis; Nanospheres - chemistry; Nickel - chemistry; Water Purification - methods
• ISSN: 1477-9234
• DOI: 10.1039/c5dt02724a

NiS2 hollow spheres are successfully prepared by a one-step template free method. Meanwhile, α-NiS hollow spheres can also be synthesized via the calcination of the pre-obtained NiS2 hollow spheres at 400 °C for 1 h in air. The electrochemical performances of the as-prepared NiS2 and α-NiS hollow sphere products are evaluated. When used for supercapacitors, compared with NiS2 hollow spheres, the α-NiS hollow sphere electrode shows a large specific capacitance of 717.3 F g(-1) at 0.6 A g(-1) and a good cycle life. Furthermore, NiS2 and α-NiS hollow spheres are successfully applied to fabricate non-enzymatic glucose sensors. In particular, the α-NiS hollow spheres exhibit good catalytic activity for the oxidation of glucose, a fast amperometric response time of less than 5 s, and the detection limit is estimated to be 0.08 μM. More importantly, compared with other normally co-existing interfering species, such as ascorbic acid, uric acid and dopamine, the electrode modified with α-NiS hollow spheres shows good selectivity. Moreover, the α-NiS hollow spheres also present good capacity to remove Congo red organic pollutants from wastewater by their surface adsorption ability.