Fuel-dependent, shape-selective, distinct blue and green photoluminescence from α-Bi2O3 and β-Bi2O3 synthesised using microwave combustion

In the current study, alpha-Bi2O3 and beta-Bi2O3 were synthesised using a one-step, novel, solid-solid combustion technique. The reaction rate was increased with the use of microwaves (molecular heating) compared to direct or indirect heating. A strong relationship was observed between the fuel, polymorphic structure, shape and optical properties of the synthesised Bi2O3. Photoluminescence studies reveal that two major visible emissions are observed for all samples. The two emissions are distinct with a broad peak in blue and a narrow peak in green. The intensity of the green characteristic emission depends strongly on the heating method used for synthesis and is more intense for microwave-synthesised samples.

Automated summary

In this study, alpha-Bi2O3 and beta-Bi2O3 were synthesized using a novel one-step solid-solid combustion technique. The use of microwaves as a molecular heating method increased the reaction rate compared to direct or indirect heating. There was a strong relationship between the fuel, polymorphic structure, shape, and optical properties of the synthesized Bi2O3. Photoluminescence studies showed two major visible emissions for all samples, with a broad peak in blue and a narrow peak in green. The intensity of the green characteristic emission depended strongly on the heating method used for synthesis and was more pronounced in samples synthesized with microwaves.