Applying first principles calculations we have explored the effect of metal atoms on the superconducting properties of decahydrides of Gallium (Ga), Niobium (Nb) and Molybdenum (Mo) at 150 GPa. These atoms owing to their apt electronegativities, metallic radii and other physical parameters stabilise the host guest type clathrate structure of decahydrides. Our calculations show the highest density of state (DOS) (N(E_F) = 2.62 states/eV/f.u.) at the Fermi level for NbH₁₀ along with presence of van Hove singularity among all decahydrides. This N(E_F) value is ~163% enhanced compared to that of LaH₁₀ at 150 GPa making it a sought for high TC material. Our correlative analysis establishes a pivotal role for chemical properties, in particular, electronegativity of metal atoms in tuning the H–H distances and hence the superconductivity of decahydrides.