The nanocomposite of polyaniline and nitrogen-doped layered HTiNbO5 with excellent visible-light photocatalytic performance

Abstract

An effective approach has been used to synthesize N-doped HTiNbO₅ (denoted as N-HTiNbO₅) with a better intercalation property. The synthesis of polyaniline (PANI) with N-HTiNbO₅ to form PANI–N-HTiNbO₅ lamellar nanocomposites by in situ polymerization using the aniline (ANI) intercalation compound ANI/N-HTiNbO₅ as the intermediate has been investigated. The resulting PANI–N-HTiNbO₅ nanocomposite showed a better crystallinity with a monolayer of PANI within the interlayers of N-HTiNbO₅, because nitrogen doping can affect the surface charge distribution of [TiNbO₅]⁻ layers. The cyclic voltammetry (CV) results indicated that the PANI–N-HTiNbO₅ nanocomposite had good redox activity and electrochemical-cycling stability in acidic solution. The visible-light response of the PANI–N-HTiNbO₅ nanocomposite was enhanced through N-doping, acid exchange, and the intercalation of PANI. The PANI–N-HTiNbO₅ nanocomposite showed the highest activity with 97.8% methylene blue (MB) photodegraded in 170 min under visible light irradiation. The significant enhancement of photocatalytic performance can be attributed to the high efficiency of charge separation, induced by the synergistic effect between PANI and N-HTiNbO₅. In addition, the PANI–N-HTiNbO₅ nanocomposite had a high thermal and photodegradation stability due to the intercalation reaction at the molecular level.