Influence of Cu doping in Magnesium Hydroxide Nanoparticles for Bandgap Engineering

Abstract

Cu doped Mg(OH)₂ nanoparticles were synthesized with varying concentrations from 0 to 10% by a chemical synthesis technique of coprecipitation. X-rays diffraction (XRD) of the samples confirms that all the samples acquire the hexagonal crystal structure. XRD results indicated the solubility limit of dopant in the host material and the secondary phase of CuO was observed beyond 3% Cu doping in Mg(OH)₂. The reduction in the size of nanoparticles was observed from 166 to 103 nm for Mg(OH)₂ and 10% Cu doped Mg(OH)₂ samples, respectively. The shift in absorption spectra exhibited the systematical enhancement in optical bandgap from 5.25 to 6.085 eV. A good correlation was observed between the bandgap energy and crystallite size of the nanocrystals which confirmed the size induced effect in the nanoparticles. The transformation in the sample morphology was observed from irregular spherical particles to sepals like shapes with increasing the Cu concentration in the host material. The energy dispersive X-Ray (EDX) analysis confirmed the purity of mass percentage composition of the elements present in the samples.

Keywords

Cu doped Mg(OH)₂ / nanoparticles / phase purity, optical band gap / morphologies

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