The exploration of metal/metal oxide nanocomposites as catalysts for hydrogen and oxygen evolution is highly desirable for renewable and clean energy applications. Cu/Cu2O nanocomposites have obtained one step process by thermal decomposition of aligned copper oxalate nanorods and CuO in 2:1 molar ratio in argon atmosphere at 350 degrees C. Hydrogen and oxygen evolution reaction (HER and OER) were carried Out using these catalyst on glassy carbon as working electrodes in KOH electrolyte solution. Cu/Cu2O nanocomposites produce 8 times higher current density than Cu and 4.5 times higher than Cu2O during HER whereas in case of OER study, it is 36 times higher than Cu and 2.9 times higher than Cu2O. The electrocatalyst is highly stable over 50 cycles. Our studies show an improvement in electrocatalytic activity by properly choosing the composite, and thus, it may be expanded to other electrocatalysts for obtaining increased activity. (C) 2015 Elsevier Ltd. All rights reserved.