The theoretical calculations indicate that the metal doped BN sheets are potential materials to store the hydrogen and tune the band gap. The BN sheet is a nonmagnetic wide-band-gap semiconductor. We predict that 2D h-BN-like sheet material (h-ScN sheet) has special properties, above all, strong adsorption H-2, tuning the band gap and others potential properties. Using Density Functional Theory (DFT), the lattice parameters of Al/Cr doped ScN sheets are optimized, which are still kept on 2D planar geometry, and the band gap and H-2 storage are studied. The simulation results show that the ScN sheet is a nonmagnetic narrow-band-gap semiconductor, in which the band gap is only 1.130 eV. We find that the H-2 molecule can be easily absorbed by Al/Cr doped N in ScN sheet, and the band gap is very easy to be tuned by Al/Cr doped ScN sheet. The band gap decreases from 1.130 eV to 0.041 eV. So Al/Cr doped ScN sheet is a promising material in storage H-2 and tuning the band gap. (C) 2015 Elsevier B.V. All rights reserved.