Mesoporous carbons (MCs) with high surface area of 1527-1634 m(2) g(-1) for supercapacitors are made from biomass such as peanut shell and rice husk by one-step zinc chloride (ZnCl2) activation assisted with microwave heating. At higher current density, the MCs made by the microwave heating show both higher energy and higher power density than the MCs made by the conventional heating because of bigger average pore size and unique mesopore structure in the MCs made by the microwave-assisted technique. It has been found that the supercapacitors made from the MCs by the microwave-assisted method have a high energy density of 19.3 Wh kg(-1) at high power density of 1007 W kg(-1) in 1 M Et4NBF4/PC electrolyte, suggesting that the microwave-assisted one-step ZnCl2 activation technique is an efficient approach to the production of biomass-derived MCs with high performance for supercapacitors. (C) 2013 Elsevier B.V. All rights reserved.