Tetravalent lead in nature

Of the three industrially important lead oxides PbO, Pb3O4 and PbO2 [1-4] the first two are readily accessible through chemical synthesis, whereas PbO2 can only be reached through high pressure, electrochemical or strongly oxidizing synthesis routes [5-7].

In nature lead dioxide forms oxidatively during hydrothermal mineralization [8]. The respective β modification, named plattnerite is a rare mineral and has hitherto only been characterized by powder X-ray or neutron diffraction.

The samples studied originate from Mine du Pradet in Cap Garonne, France and from Mount Trevasco in Bergamo, Italy. Single crystal X-ray diffraction measurements show that β-PbO2 crystallizes in the rutile-type structure with space group P42/mnm without additional reflections or a sign for a structural transformation between room temperature and 90 K [9].

[1] G. Hantke, Gmelins Handbuch der anorganischen Chemie, 8. Auflage, Verlag Chemie, Weinheim, 1969.

[2] K. Rumpf, Gmelins Handbuch der anorganischen Chemie, 8. Auflage, Verlag Chemie, Weinheim, 1973.

[3] H. E. Brown, Lead oxide – Properties and Applications, International Lead Zinc Organization, New York, 1985.

[4] D. L. Perry, Lead Oxides: Synthesis and Applications, in Transparent Electronics, (Eds.: A. Facchetti, T. J. Marks) John Wiley & Sons, West Sussex, 2010.

[5] G. L. Clark, et al., J. Am. Chem. Soc., 1937, 59, 2305.

[6] W. B. White, R. Roy, J. Am. Ceram. Soc., 1964, 47, 242.

[7] E. Torikai, Y. Kawami, US Patent 3,959,453, 1976.

[8] J. E. Taggart Jr., et al., Can. Mineral., 1988, 26, 905.

[9] C. Paulsen, et al., Z. Naturforsch., 2019, 74, 427.