Multicomponent equiatomic rare earth oxides with a narrow band gap and associated praseodymium multivalency.

New multicomponent equiatomic rare earth oxides (ME-REOs) containing 3-7 rare earth elements (Ce, Gd, La, Nd, Pr, Sm and Y) in equiatomic proportions are synthesized using nebulized spray pyrolysis. All the systems crystallized as a phase pure fluorite type (Fm3[combining macron]m) structure in spite of the high chemical complexity. A nominal increase in the lattice parameter compared to CeO is observed in all ME-REOs.

Chemical vapor synthesis of nanocrystalline perovskites using laser flash evaporation of low volatility solid precursors.

One key requirement for the production of multinary oxide films by chemical vapor deposition (CVD) or nanocrystalline multinary oxides particles by chemical vapor synthesis (CVS) is the availability of precursors with high vapor pressure. This is especially the case for CVS where much higher production rates are required compared to thin films prepared by CVD. However, elements, which form low valent cations such as alkaline earth metals, are typically only available as solid precursors of low volatility, e.