1 research outputs found
Mg-Doped ZnO Nanoparticles for Efficient Sunlight-Driven Photocatalysis
Magnesium-doped ZnO (ZMO) nanoparticles were synthesized
through
an oxalate coprecipitation method. Crystallization of ZMO upon thermal
decomposition of the oxalate precursors was investigated using differential
scanning calorimetry (DSC) and X-ray diffraction (XRD) techniques.
XRD studies point toward a significant <i>c</i>-axis compression
and reduced crystallite sizes for ZMO samples in contrast to undoped
ZnO, which was further confirmed by HRSEM studies. X-ray photoelectron
spectroscopy (XPS), UV/vis spectroscopy and photoluminescence (PL)
spectroscopy were employed to establish the electronic and optical
properties of these nanoparticles. (XPS) studies confirmed the substitution
of Zn<sup>2+</sup> by Mg<sup>2+</sup>, crystallization of MgO secondary
phase, and increased Zn–O bond strengths in Mg-doped ZnO samples.
Textural properties of these ZMO samples obtained at various calcination
temperatures were superior in comparison to the undoped ZnO. In addition
to this, ZMO samples exhibited a blue-shift in the near band edge
photoluminescence (PL) emission, decrease of PL intensities and superior
sunlight-induced photocatalytic decomposition of methylene blue in
contrast to undoped ZnO. The most active photocatalyst 0.1-MgZnO obtained
after calcination at 600 °C showed a 2-fold increase in photocatalytic
activity compared to the undoped ZnO. Band gap widening, superior
textural properties and efficient electron–hole separation
were identified as the factors responsible for the enhanced sunlight-driven
photocatalytic activities of Mg-doped ZnO nanoparticles