Biosynthesis, Optical and Magnetic Properties of Fe-Doped ZnO/C Nanoparticles

Employing a self-combustion method supported by egg white, pure and Fe-doped ZnO/C nanoparticles successfully biosynthesized. XRD, FTIR, Raman, SEM/EDS and TEM measurements were used to characterize the pure and doped systems. The materials under investigation’s optical, surface and magnetic characteristics were recognized. Only one zinc oxide crystalline phase exhibiting a hexagonal shape comparable to wurtzite was present in the systems of pure and Fe-doped ZnO/C. Due to the variation in ionic radii, doping ZnO/C system with iron ions resulted in a decrease in unit cell volume; it revealed that ions of iron had been integrated into the lattice of zinc oxides. FTIR analysis shows characteristic vibration modes related to ZnO and that of carbon groups, confirming the formation of the ZnO/C system. In a perfect match with the IR data, which represent two bands at 1120 and 1399 cm−1 attributed to carbon groups, the Raman analysis shows that in the freshly manufactured materials, sp2 and disordered G and D carbon bands have both graphitized. Fe-doping of the ZnO/C system with different amounts of iron ions resulted in the change in the size and agglomeration of the particle’s system. The doped ZnO/C system has a surface area smaller than that of the pure system due to the decrease in both the mean pore radius and the total pore volume. Doping the ZnO/C system with 2 and 5 mol% Fe2O3 resulted in optical band gaps expanding from 3.17 eV to 3.27 eV and 3.57 eV, respectively. Due to the doping with iron ions, a magnetic transition from a fully diamagnetic state to a slightly ferromagnetic state was detected.