As a representative catalyst for the hydrolysis of NaBH4 to produce hydrogen, nanostructured Co has received intensive attention owing to its high catalytic activity and low cost. In this study, nanostructured Co films supported on Cu foils are fabricated by a facile and cost effective magnetic-field-induced chemical reduction method. By controlling the synthetic conditions, Co films composed of nano-platelets, nanosheets and microspheres are successfully obtained. It is found that the as-prepared nanostructured Co film catalysts exhibit high performance in the hydrolysis of sodium borohydride. The rate constant/apparent activation energy of NaBH4 hydrolysis in the presence of these Co film catalysts is 1.27 mL min(-1) cm(-2)/28.4 kJ mol(-1), 0.96 mL min(-1) cm(-2)/27.6 kJ mol(-1) and 0.85 mL min(-1) cm(-2)/34.3 kJ mol(-1), respectively. Interestingly, Co film composed of nanoplatelets shows only ca. 10% catalytic activity loss after 10 cycles, which exhibits much improved reusability and durability in contrast to those Co catalysts reported in the literature. (C) 2013 Elsevier B.V. All rights reserved.