Ti-doped B/N substituted benzene complexes for hydrogen storage: A comparison

Abstract

Structural, electronic and hydrogen storage properties of Ti-doped boron(B)/nitrogen(N) substituted benzene complexes are studied and compared with Ti-doped benzene (BTi) complex using ab initio calculations. The H2 uptake capacity is increased and decreased for B-substituted BTi (BBTi) and N-substituted BTi (BNTi) complexes respectively than that for BTi complex. However, H2 molecules interact more strongly with BNTi than BTi and BBTi complexes. The BBTi is an electron deficient structure and accepts an additional electron which is responsible for the adsorption of one extra H2 molecule than BTi and BNTi complexes. More number of states are introduced above the highest occupied molecular orbitals after B-substitution than N-substitution. The charge on Ti in BBTi is more positive than BTi and BNTi complexes. There is a Kubas type interaction between adsorbed H2 molecules and Ti atom for all the complexes.