“…It is well known that the method of synthesis plays a key role in influencing the final desired properties of nanopigments. A variety of techniques, such as solid state reaction (Hagiwara et al , 2010; Suzuki et al , 2007), combustion (Merino et al , 2015; Salem et al , 2012), sol-gel (Kurajica et al , 2012; Salavati-Niasari et al , 2009; Sales et al , 1997; Yu et al , 2009), hydrothermal (Yu et al , 2009), micro-emulsion (Giannakas et al , 2007), polymeric precursor (de Souza et al , 2009) and liquid-feed flame spray pyrolysis method (Granados et al , 2015; Granados et al , 2016), have been developed successfully obtaining cobalt aluminate oxides. Although Co x Zn 1-x Al 2 O 4 pigments have been synthesized by different techniques, no study has been done dealing with the use of polyacrylamide gel method.…”