Synthesis of Ni(OH)2 in micellar environment: structural, spectroscopic, and electrochemical studies

Abstract

This work describes the chemical synthesis of nickel hydroxide in the presence of cationic and anionic surfactants (dodecyl benzene sulfonate, DBS−, and cetyltrimethylammonium, CTA+). The materials were characterized by X-ray diffraction, infrared spectroscopy, and thermogravimetric analysis. Our findings highlighted that the synthesis in the presence of anionic DBS−, the α-Ni(OH)2 structure was preferentially formed. This material showed a high structural disorder and a high amount of intercalated species, suggesting the presence of both micelles and individual surfactants. On the other hand, the synthesis performed in the presence of CTA+ has not showed any drastic change in the material structure compared with pure Ni(OH)2; nevertheless, the intercalated cationic surfactant was identified by FTIR measurements. The enhanced electrochemical response found for the Ni(OH)2/DBS− over the Ni(OH)2/CTA+ modified electrodes can be attributed to the enhancement of the ionic diffusion through the solid material as an effect of the high structural disorder and the presence of the excess of the negative electric charge in the Ni(OH)2 sheets.