MgO nanostructures were synthesized by microwave-assisted thermal oxidation method [2]. Mg
commercial powders mixing with activated carbon were used as a precursor materials, with the
weight ratio of 1:0.125, 0.25, 0.5 and 1 g, respectively. The mixed powders were ground in a mortar
for 1 h by hands. After that the mixed powders (~0.5 g) were put into a quartz tube, which has a
diameter and length about 2.8 and 20 cm, respectively then placed in a microwave oven and the
reaction was carried out under ambient air, at the power and frequency setting of 750 Watt and 2.45
GHz, respectively.
The crystal structure of MgO nanoparticles were determined by X-ray diffractrometry. Then, the
morphologies of MgO nanoparticles were characterized by field emission scanning electron
microscopy operating at a voltage of 15.0 kV and transmission electron microscopy operating at 200
kV. The optical properties were obtained by UV-Visible spectroscopy.
The DSSCs structure used in this experiment was shown as schematic diagram in Fig. 1 (a). The
doctor-blade technique was adopted to prepare the porous film on a conducting fluorine-doped tin
oxide coated glass (FTO, 10Ω/sq). The ZnO paste was obtained by mixing of ZnO powders and
polyethylene glycol (PEG) solution with ZnO content of 50% by weight. The paste was screened on
FTO which controlled the thickness of the film by adhesive tapes and heated at 400oC for 1 hour
following the procedures reported in the literature [3]. The ZnO films on FTO were then coated with
thin layer of MgO by spin coating technique. All of MgO powders were mixed in PEG solution.
These films were heated at 400oC for 1 h. Photoelectrode thickness were observed by crosssectional
FESEM image.