Preparation of monodisperse cerium oxide particle suspensions from a tetravalent precursor

Abstract

Cerium oxide particles are a unique material that enables studying the intersection of metal oxides, f-elements, and nanomaterials. Distinct from diverse applications in catalysis, energy, and medicine, cerium possesses additional influence as a non-radioactive actinide surrogate. Herein, we present a synthesis for sub-micron cerium particles using hexamethylenetetramine and ammonium hydroxide as precipitating agents with a Ce^IV precursor. The combinatorial homogeneous precipitation approach yields monodisperse and moderately-stable CeO₂ particle suspensions in ethanol, as determined by powder X-ray diffraction, scanning electron microscopy, dynamic light scattering, and zeta potential measurements. Various additives may be used to moderate and manipulate the surface charge of the particles. Proof-of-concept electrophoretic deposition of the particles produces a uniform layer of CeO₂ on graphite. The synthesis and suspension properties are developed as a methodology towards future controlled actinide hydrolysis and film deposition.