4.3. Surface morphology
Figure 3 shows SEM images of BZC and BZC/rGO. The majority of particles
in BZC were below 100 nm with an average of 94 nm size. Although some
micron size particles were also visible. In BZC/rGO, the average
particle size remains the same as that of BZC. The surface morphology of
BZC and BZC/rGO composite is comparable. The bigger size disparity from
the size determined by XRD might be due to the fact that XRD estimates
the crystalline size, which varies from the size observed by SEM.
Another aspect is that nano-scale particles tend to cluster due to their
small size and large surface area, resulting in a secondary particle
that is larger than the original particles.