Recently, two dimensional graphenelike i.e. Si2BN solid monolayer have attracted much attention for the use of hydrogen developments. The work is based on first principles calculations using density functional theory with long range van der Waal (vdW) interactions. The optimized structure is energetically more stable due to high formation energy 45.39 eV with PBE and 50.82 eV with HSE06 functionals, respectively. Our ab-initio studies show that Pd (palladium) adatoms secured graphenelike Si2BN solid via two types of interactions; physisorption and chemisorptions reactions, which engrossing up to 3H(2) molecules signifying gravimetric limits of approximate to 6.95-10.21 wt %. The absorption energies vary from -0.31 eV to -1.93 eV with Pd-adatom and without Pd-adatom respectively, and it varies up to -1.24 eV. The work function of pure Si2BN is 5.36 eV while metal-adatom on monolayer Si2BN with (1 to 6)H-2 molecules is 3.53 eV -4.99 eV and reaches up to 5.85 eV. The theoretical study suggests that the functionalized graphenelike Si2BN is efficient for hydrogen storage and propose a possible improvement for advantageous storage of hydrogen at ambient conditions. 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.