Anchoring platinum nanofibers on nickel hydroxide nanosheets for electrochemical detection of ammonia-nitrogen in the aqueous environment

This work introduced a novel electrochemical sensor using platinum nanofibers on nickel hydroxide nanosheets and Ni foam as conductive substrate (Pt-Ni(OH)2-NF) for the detection of high sensitivity of ammonia-nitrogen via differential pulse voltammetry (DPV) technique. This Pt-Ni(OH)2-NF sensor was synthesized using a simple two-step synthesis method. Firstly, Ni(OH)2-NF was synthesized by the solvothermal reaction. And then, the platinum nanofibers (Pt) were electrodeposited on the Ni(OH)2-NF to achieve Pt-Ni(OH)2-NF. The synthesized Pt-Ni(OH)2-NF was detected using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and element map and X-ray photoelectron spectroscopy (XPS). The DPV technique was used to measure the detection ability towards ammonia-nitrogen under optimum conditions of prepared Pt-Ni(OH)2-NF. The detection limit of 2.74 mu M and linear range from 5 mu M to 500 mu M were calculated with high sensitivity of 12.27 mu A mu M-1 cm-2. The measured results indicated that the fabricated sensor has good repeatability and excellent stability in ammonia-nitrogen determination. This sensor also showed good recoveries in determining ammo-nia-nitrogen in tap water and lake water samples.