Hydrothermal method to prepare porous NiO nanosheet

Porous NiO nanosheet has been synthesized by hydrothermal method, using Ni(NO3)2·6H2O and urea as the raw materials and DI water as solvent, then followed by calcination process. It has been indicated by TEM and BET analysis that the as-prepared NiO was porous nanosheet. With the increase of annealing temperature, the pore size on the nanosheet becomes larger and the specific surface area becomes much smaller. All isotherms of NiO display type IV with H3 type hysteresis loop with pore size distribution of 2–60 nm. The annealing temperature turns out to be the key factor to pore size, pore distribution and pore volume.

► Porous NiO nanosheet was prepared via hydrothermal method.
► With increase of annealing temperature, the surface area become much smaller and pore size gets larger.
► The annealing temperature is the key factor to control pore size, distribution and pore volume.