Contact Potential of Nickel

W. Ende measured the gas-metal contact potential difference between pieces of the same metal in air and in vacuo; and M.Andauer obtained -0.32 volt for the potential of nickel in air. S. J. French and L. Kahlenberg studied the gas-metal electrode of nickel in hydrogen, oxygen, and nitrogen. R. D. Kleeman and co-workers studied the negative charge assumed by nickel in contact with a liquid. The contact potential of nickel was studied by M. Forro and E. Patai, P. H. Dowling, H. Kosters, and O. Stierstadt. G. N. Glasoe found 0.20 volt for the contact potential of nickel and iron; G. Monch measured the effect with nickel and copper, and nickel and silver; and J. E. Schrader found the contact potential of nickel and copper to be 0.25 volt, and with simultaneous heat treatment of the metal, the difference of potential was -0.15 volt with high frequency, induced current. O. Scarpa, and E. Dubois also studied the Volta effect; and L. Bernoulli, V. Freedericksz, and A. Hesehus, the position of nickel in Volta's contact series.