Facile synthesis of Mn-doped ZnO nanoparticles by flash combustion route and their characterizations for optoelectronic applications

In the present article, the pure and different concentrations as 1, 2, 3, and 5 wt.% Mn-doped ZnO (Mn:ZnO) nanoparticles were synthesized by combustion route. XRD of the prepared samples were fitted using the Lorentz function and the obtained data files were used to calculate the crystallite size. The crystallite sizes were found to be 25.3 nm, 34.6 nm, 31.1 nm, 32.5 nm, and 33.3 nm for pure, 1 wt.%, 2 wt.%, 3 wt.%, and 5 wt.% Mn-doped ZnO NPs, respectively. The agglomerated spherical shape morphology with different particles sizes of pure and 1, 3, and 5 wt.% Mn:ZnO NPs were observed by scanning electron microscopy (SEM). The vibrational phonon modes observed at 99-100, 326-331, 435-438, 573-585, 676-681, and 1142-1151 cm(-1) were attributed to the presence of intrinsic defects in the samples. The optical band gaps 3.280, 3.218, 3.103, 3.024, and 2.922 eV of pure, 1 wt. %, 2 wt.%, 3 wt.%, and 5 wt.% Mn-doped ZnO NPs were obtained using Kubelka-Munk function, respectively. PL emission spectra exhibit the peaks at 354, 451, 469, 482, 492, and 560 nm under 325 nm excitation wavelength, while emission peaks observed at 389, 451, 468-474, 492, and 557 nm under 350 nm excitation wavelength. The dielectric constant and dielectric losses of the prepared NPs were observed in the range 27.6-23.4 and 29-14, respectively. The greater values of capacitance and impedance of the prepared samples were recorded as 27.3-17.3 (pF) and 2.75 (M omega)-273 (omega) over the entire range of the logarithmic frequency. The obtained results of Mn:ZnO nanoparticles were found suitable for the potential applications in optoelectronic devices.

Automated summary

In this study, manganese-doped zinc oxide nanoparticles with various concentrations were synthesized using the combustion route. The crystallite size, morphology, optical properties, and electrical properties of the prepared nanoparticles were studied. The results showed that the manganese doping affected the crystallite size, surface morphology, vibrational phonon modes, optical band gap, and electrical performance of the zinc oxide nanoparticles, which are important for the development and application of optoelectronic devices.