An investigation into the formation and conversion of metal complexes to metal oxide nanoparticles in supercritical water

- Aqueous solution of various metal nitrate salts were treated in a supercritical water reactor at 400 and 500 °C.
- The treated salts were Zn(II), Cu(II), Mn(II), Ce(III), Mg(II), Ni(II), Zr(IV), and Ag(I) nitrates.
- Metal hydroxynitrate was found to be the major byproduct of the metal oxide formation reaction.
- Temperature showed a very significant effect on the decomposition of metal hydroxynitrates.
- A general mechanism including the formation/conversion of the studied metal complexes was suggested.