Structural evolution of NiAl-based layered nanostructures grown by a low-temperature hydrothermal method

Abstract We report on the growth mechanism of NiAl-based layered nanostructures on rigid substrates using a low-temperature hydrothermal method. NiAl-layered double hydroxide (LDH) structures were grown with various source concentrations and growth times. Structural and optical investigations showed that uniform NiAl-LDHs were grown on the substrates because Al(OH) 3 was sufficiently supplied from the aluminum thin film seed layer when the Ni source concentration was low and in the initial stage of the growth. However, a bilayer of NiAl-LDH and α-Ni(OH) 2 was formed when the Ni sources were sufficiently supplied and the growth time was long enough because of the deficient Al(OH) 3 sources at the growth front.