Initial stages of bismuth oxide formation

Data on electron diffraction study of bismuth films during heating are presented for various partial oxygen pressures in the gas phase. The formation of bismuth oxide phases is completed in several seconds.     

Initial stages of the formation of lead oxide phases

Metal lead films are studied by electron diffraction during heating depending on temperature T and oxygen partial pressure p _O2 in the gas phase. It is found that the formation of oxide phases begins from the α-PbO₂ modification. As p _O2 increases or T increases, intermediate oxides nPbO₂ · mPbO and Pb₃O₄ form and then transform into the β-PbO modification.