Electrolytic hydrogen absorption by double- or triple-walled carbon nanotubes

Electrolytic hydrogen absorption in 5 М KОН solution by double- or triple-walled carbon nanotubes (CNТs), which are applied onto a steel membrane and capsulated by an electrolytic nickel layer with a thickness of 10 nm, is studied. CNТs are produced by catalytic pyrolysis of methane and characterized by an inner diameter of 2–4 nm, length of up to 10 μm or more, and a specific surface of 600–800 m 2 g –1 . Investigations are carried out using the electrochemical diffusion technique, cyclic voltamperometry, and electrochemical impedance spectroscopy. Data on the accumulation of electrolytic hydrogen by double- or triple-walled CNТs agree with previously obtained results for multiwalled carbon nanotubes and are in a range of 5–14%. However, the observed scatter of experimental results is probably caused by bifurcation characteristic for nanoobjects.