Phase analysis and reduction behaviour of Ce dopant in zirconolite

Zirconolite, a potential matrix for the immobilization has been studied to investigate the doping behaviour of Ce in its structure to design a nuclear waste form that can accommodate both trivalent and tetravalent nuclear wastes. So, samples have been prepared as per the composition Ca 0.8 Ce 0.2 ZrTi 1.8 Al 0.2 O 7 using solid-state method and analysed for their structural, micro-structural and chemical properties. A dense-packed structure was found in SEM with the phase of zirconolite-2M as confirmed by XRD and Raman techniques. Quantitative analysis of XPS inferred that the percentage of Ce(III) in the sample was about ~ 75% indicating the reduction of Ce at higher temperatures.