Ceria nano architectonics with doping effect of Co2+ on pinkish red luminescence and high energy storage applications: Ceria nano architectonics with doping effect...: R. Munirathnam et al.

In this present investigation, we have successfully synthesized Co 2 + doped CeO 2 nanoparticles (NPs) within the dopant range of 1–11 mol% using a versatile solution combustion synthesis method, employing Aloe vera extract as a potent reducing agent. To substantiate the efficacy of our synthesis process, we employed a diverse array of characterization techniques. The PXRD analysis unequivocally confirmed the formation of a cubic fluorite structure characterized by the Fm-3m space group. The average crystallite size computed from both the Scherrer equation and W–H plot is found to be in the range of 14.98–19.52 nm. Notably, our investigation revealed a consistent decrease in the average crystallite size from 19.52 to 16.68 nm and an increase in the direct energy band gap from 3.069 to 3.078 eV as the Co dopant concentration increased from 1–11 mol%. Surface morphology analysis confirmed the formation of NPs with a high degree of agglomeration with irregularly shaped NPs arranged one over the other. The photoluminescence emission spectra were recorded at an excitation wavelength of 390 nm showing a strong emission peak at 697 nm. At 7 mol% doping concentration quenching is noticed. CIE coordinates confirmed the Co 2 + doped CeO 2 NPs fall under red color with CCT values from 1713 to 1796 K i.e. warm light. Electrochemical analysis reveals the specific capacitance range of NPs is from 26 to 52.5 F/g. The energy density is found to be highest i.e. 1419 Wh/g for 7 mol% Co doped CeO 2 NPs. Collectively, our research suggests a promising avenue for the practical application of these NPs in advanced energy storage devices. [ABSTRACT FROM AUTHOR]