Boron-doped nickel oxide(B-NiO) nanoflowers are prepared by simple thermal decomposition of nickel hydroxide.B-NiO is porous sphere with a diameter of about 400 nm.B-NiO nanoflowers are composed of approximately 30 nm nanoplates and the thickness of the nanosheets is approximately 3 nm. The specific surface area of the material is as high as 200 m(2) g(-1) and the pore size distribution curves of B-NiO has three typical peaks in the range of mesoporous (5 nm, 13 nm and 18 nm). As an electrode for supercapacitors, the crystallineB-NiO nanoflowers have favorable characteristics, for instance, a specific capacitance of 1309 Fg(-1) at a current density of 3 Ag-1 and no significant reduction in Coulombic efficiency after 2500 cycles at 37.5 Ag-1. This remarkable electrochemical performance will makeB-NiO nanoflowers a promising electrode material for high performance supercapacitors. (C) 2014 Elsevier Ltd. All rights reserved.