Nickel hydroxide nanoparticles were fabricated on Vulcan XC-72R carbon black using various reducing agents through assisted microwave polyol process. The formed electrocatalysts using sodium borohydride [Ni(OH)(2)/C-NB], ethylene glycol [Ni(OH)(2)/C-EG] and a mixture of them [Ni(OH)(2)/C-NB] displayed an electrocatalytic activity towards urea oxidation in NaOH solution. The oxidation peak potential and current density values were greatly influenced by the employed reducing agent. Lower onset and peak potential values were measured at Ni(OH)(2)/C-EGNB, while Ni(OH)(2)/C-EG exhibited the highest oxidation current density during urea oxidation reaction. Electroactive surface area measurements revealed that the number of available active sites for the oxidation reaction was arranged in an ascending order as Ni(OH)(2)/C-NB < Ni(OH)(2)/C-EGNB < Ni(OH)(2)/C-EG. The diffusion coefficient of urea molecules at Ni(OH)(2)/C-EG and Ni(OH)(2)/C-EGNB was 14.69 and 5.90 times higher than that at Ni(OH)2/C-NB. Stable performance was measured at all studied electrocatalysts over prolonged operation suggesting their valuable application as efficient anode materials in direct urea oxidation fuel cells. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.