Nanotubes and nickel combine to give catalyst like hydrogenase enzyme. By latching a nickel compound onto multiwalled carbon nanotubes, researchers in France have created a new catalytic material for use as proton-exchange membrane for electrolyzers and fuel cells. By immobilizing their catalyst on nanotubes, the researchers were able to make it work under aqueous conditions which is a requirement for practical use in proton-exchange membrane devices. The nanotube-catalyst material is claimed to exhibit extreme stability, standing up to more than 100,000 turnovers for H2 production and more than 35,000 turnovers for the reverse reaction.