Nanocomposite of polyaniline and a layered niobate acid host: Synthesis, electrochemical studies, and photocatalytic properties

The synthesis of polyaniline (PANI) with H₄Nb₆O₁₇ (HNbO) to form PANI/HNbO lamellar nanocomposite by in situ polymerization using aniline (ANI) intercalation compound ANI/HNbO as the intermediate has been investigated. The properties of the samples were characterized by means of XRD, SEM, TEM, FT‐IR, UV–vis spectroscopy, and TG‐DTA. The in situ polymerization of ANI packed in a regular orientation in a mono‐ and bilayers (i.e., pseudo‐bilayers) structure within the HNbO interlayers led to PANI/HNbO nanocomposite powder using (NH₄)₂S₂O₈ as the catalyst with PANI monolayer packing orientation within the HNbO interlayers. PANI/HNbO nanocomposite showed improved thermal stability compared with original PANI by TG analysis. The PANI/HNbO nanocomposite was studied by cyclic voltammetry (CV), which indicated the good redox activity and electrochemical‐cycling stability in acidic solution. The interaction between PANI and nanosheets greatly affected the electrochemical behavior of PANI/HNbO nanocomposite. Two couples of redox peaks corresponded to two oxidation process of PANI in acid conditions. The PANI/HNbO nanocomposite exhibited much higher photocatalytic activities for the degradation of methylene blue (MB) in aqueous solution under visible light irradiation than HNbO itself. POLYM. COMPOS., 34:834–841, 2013. © 2013 Society of Plastics Engineers