Sol–gel auto-combustion synthesis of PbFe12O19 using maltose as a novel reductant

Abstract

A new way of preparing lead hexaferrite (PbFe₁₂O₁₉) nanoplates and nanoparticles has been developed using the sol–gel auto-combustion route, without adding external surfactant. For the first time, maltose has been applied as reductant to form PbFe₁₂O₁₉. In this work, we have chosen lead nitrate and iron nitrate as starting reagents. The morphology, phase structure, composition and phase purity of PbFe₁₂O₁₉ can be controlled by adjusting the Pb/Fe and Pb : reductant ratios and also calcination temperature. When the molar ratio of Pb/Fe is 1 : 6 and calcination temperature is 900 °C, the product is pure and found to be PbFe₁₂O₁₉ nanoplates. The size and agglomeration of the nanoplates increase with decreasing maltose content. On decreasing the calcination temperature to 600 °C, nanoparticles with spherical morphology are obtained. The PbFe₁₂O₁₉ nanostructures are characterized using SEM, TEM, EDS and XRD. Products with a high coercive force of 5609 Oe are obtained when the Pb/maltose and Pb/Fe ratios are 1 : 26 and 1 : 6, respectively, and calcination temperature is 900 °C.