Coordinatively unsaturated iron metal sites were introduced in the tris(aminophenyl) bezene-terephthalaldehyde framework to facilitate Kubas type metal-hydrogen binding for ambient temperature hydrogen storage applications. The synthesized compound was characterized via elemental analysis (EA), infrared spectroscopy (IR), thermogravimetric analysis (TGA), nitrogen adsorption-desorption (BET) and X-ray photoelectron spectroscopy (XPS). This complex exhibits a remarkably high gravimetric capacity up to 1.2 wt% at 298 K under 100 atm despite the relatively low BET surface area of 54.6 m(2)/g. The observed significant isosteric heat of hydrogen adsorption with surface coverage arises from the Kubas type of bonding supported by the results of electron paramagnetic resonance (EPR). Excellent reversibility of hydrogen adsorption was demonstrated. Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.