Homogeneous forced hydrolysis of aluminum through the thermal decomposition of urea

Homogeneous hydrolysis of aluminum by decomposition of urea in solution was achieved because the urea coordinates to the Al3+ in solution, forming [Al(H2O)5(urea)]3+ and to a lesser extent [Al(H2O)4(urea)2]3+. Upon hydrolysis more hydrolyzed monomeric species, [Al(H2O)5(OH)]2+, [Al(H2O)4(OH)2]+, [Al(H2O)4(urea)(OH)]2+, and [Al(H2O)3(urea)(OH)2]+, were formed, followed by trimeric species and the Al13 Keggin complex [AlO4Al12(OH)24(H2O)12]7+. The 27Al NMR spectra indicated the formation of other complexes in addition to the Al13 at the end of the hydrolysis reaction.