“…It signifies that multiple layers of gas adsorbate are quickly formed, pointing towards a nonporous surface, which showed a calculated mean pore diameter of 29.2 nm, which is comparable to the size range of irregularly shaped particles observed by electron microscopy. The specific surface area was 8.3 m 2 g − 1 , which corresponds to the data reported in other works, partly due to high-temperature synthesis [51].…”