Alfa Aesar sells the superoxide (KO2).  I believe you could make K2O by reacting this with K metal if you needed it to be K2O exactly.  Hope this helps

I found this - KO2 + 3K = 2 K2O (700° С, p) - I think the p means pressure though - wasn't specified

Also you could do - 2 KNO3 + 10 K → 6 K2O + N2

But K2O sounds pretty air sensitive and this reaction is going to produce some gas (so a sealed vessel may be a poor choice to keep it dry)

After heating the KOH , I think you will get K2O

KCl also  

Hi ,

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