The calculated Wulff construction is in excellent agreement with previously reported experimental particle shapes. Pan et al. described the synthesised particles as 'plate-like', with a clear basal (001) plane, which is in line with what we observe here. Considering they also report the particles like to form secondary clusters combining several primary particles, a visual comparison of the Wulff shape with the scanning electron microscopy images from the studies by Pan et al. and Wang et al. show good agreement between the two.