Transition Metal-Ethylene Complexes as High-Capacity Hydrogen Storage Media

Safe and efficient storage of hydrogen is essential for hydrogen economy. From first-principles (ab initio) calculations, we model and predict that a single ethylene molecule (C2H4) can form a stable complex with two transition metals (TM) such as Ti (red atoms). The resulting TM-ethylene complex then absorbs up to ten hydrogen molecules (green atoms), reaching to gravimetric storage capacity of ~14 wt%. Dimerization, polymerizations and incorporation of the TM-ethylene complexes in nanoporous carbon materials (such as graphene) have been also discussed. Our results are quite remarkable and open a new approach to high-capacity hydrogen storage materials discovery.

E. Durgun, S. Ciraci, W. Zhou, and T. Yildirim
Phys. Rev. Lett. 97, 226102 (2006)
[Cover page of December 1, 2006 issue].