Boron substituted Na0.44MnO2 nanorods were synthesized via conventional solid state reaction technique. Optimum synthesis temperature of the nanorods is determined as 750 degrees C. As the temperature increases, the nanorods start merging each other. As the boron content increases, amount of nanorods decrease due to the emergence of impurity phases. 12.5% boron substitution (x=0.25 in NaMn2-xBxO4 nominal composition) into Mn site striggers the formation of ultra-thin nanobristles on the surface of the nanorods. These nanobristles disappear completely in x=0.75 sample. We attribute the formation of these nanobristles to the increase in the internal energy upon increase in the unit cell volume. (C) 2016 Elsevier Ltd and Techna Group S.r.l. All rights reserved.