Transition‐Metal‐Based Multidecker Complexes as Hydrogen Storage Materials: A Theoretical Study

Hydrogen economy has gained pace globally due to the depletion of fossil fuels at an alarming rate. A good number of multidecker transition metal complexes have been studied for their hydrogen storage ability. However, the problem of finding an ideal multidecker system for hydrogen storage applications still remains a challenge. Herein, we report a comparative study on multidecker complexes of VTi(C 6 H 6 ) 3 , Sc 2 (C 6 H 6 ) 3 , and Sc 2 (C 5 H 5 ) 2 (C 6 H 6 ) using density functional theory at PBEPBE functional and 6–31G (d,p) basis set level of theory. The three complexes show hydrogen adsorption capacity in a range of 2.94 to 5.28 wt%, with an average binding energy of 0.65 to 0.92 eV/H 2 . Trends in adsorption energies, Gibbs free energy changes and energy gaps indicate the adsorption of H 2 molecules on these multidecker complexes is thermodynamically and kinetically favorable.