2.2. Characterization
We conducted scanning electron microscope (SEM) imaging on
a Hitachi S-4800 high resolution SEM unit while recording transmission
electron microscopy (TEM) images on a Hitachi H-7600
TEM unit. X-ray photoelectron spectroscopic (XPS) measurements
were made on a VG Microtech ESCA 2000 using monochromatic
Mg Ka radiation at a power of 300 W.