From a Cerium-Doped Polynuclear Bismuth Oxido Cluster to β-BiO:Ce.

The simultaneous hydrolysis of Bi(NO)·5HO and Ce(NO)·6HO results in the formation of novel heterometallic bismuth oxido clusters with the general formula [BiO(NO)(DMSO)]:Ce (DMSO = dimethyl sulfoxide; cerium content <1.50%), which is demonstrated by single-crystal X-ray diffraction analysis. The incorporation of cerium into the cluster core is a result of the interplay of hydrolysis and condensation of the metal nitrates in the presence of oxygen. Diffuse-reflectance UV-vis and X-ray photoelectron spectroscopy reveal the presence of Ce in the final bismuth oxido clusters as a result of oxidation of the cerium source. The cerium atoms are statistically distributed mainly on the bismuth atom positions of the central [BiO] motif of the [BiO] cluster core. Hydrolysis and subsequent annealing of the bismuth oxido clusters in the temperature range of 300-400 °C provides β-BiO:Ce samples with slightly lowered band gaps of approximately 2.3 eV compared to the undoped β-BiO (approximately 2.4 eV). The sintering behavior of β-BiO is significantly affected by the cerium dopant. Finally, differences in the efficiency of the as-prepared β-BiO:Ce and undoped β-BiO samples in the photocatalytic decomposition of the biocide triclosan in an aqueous solution under visible-light irradiation are demonstrated.