The invention relates to a preparation method of polyhedral nano
oxide for catalyzing. The preparation method comprises the following steps: preparing nano polyhedral
copper oxide powder by a salt melting method taking a
potassium source and a
sodium source as melted salt; dissolving
copper salt into water to prepare a solution; dropping an alkali source into the solution until the pH of the solution is 6-8; putting the solution into a constant-temperature
magnetic stirrer to be stirred at constant temperature of 60 DEG C; filtering and washing for two to three times after
sediment is generated and putting the product into a
drying oven to be dried; putting a dried precursor,
sodium salt and
potassium salt into a ball milling tank to be milled;
drying the milled
mixed solution and transferring the solution into a
crucible to be calcined; then cooling in the air to
room temperature; and filtering, washing and
drying to prepare the nano polyhedral
copper oxide powder. The preparation method has the advantages of low synthesis temperature, simplicity in operation, uniform chemical components of the synthesized
powder, good
crystal appearance and the like; and a
Rhodamine B degrading experiment shows that compared with commodity
nano copper oxide, the catalyzing performance is greatly improved.