Self-assembled lignosulfonate-inorganic hybrid nanoflowers and their application in catalytic reduction of methylene blue and 4-nitrophenol

Abstract

• Synthesis of hierarchical copper phosphate-lignosulfonate (Cu-LS) nanoflowers. • Structural confirmation of Cu-LS nanoflowers by FTIR, BET, XRD, SEM, elemental mapping and EDS analyses. • Catalytic performance of Cu-LS nanoflowers in the reduction of 4-NP and MB in aqueous media. • Cu-LS nanoflowers can be reused five times without any remarkable loss of catalytic activity. Hierarchical inorganic-organic nanostructures prepared using biosourced compounds have attracted a large amount of interest owing to their unique structure, good stability and potential applications. This study was undertaken to design efficient and green hierarchical copper phosphate-lignosulfonate (Cu-LS) nanoflowers with high catalytic sites by an eco-friendly self-assembly method for application in the catalytic reduction of organic dyes in aqueous media. The lignosulfonate played a critical role in controlling the size and morphology of Cu-LS nanoflowers. Moreover, catalytic tests showed the excellent catalytic degradation activity of Cu-LS nanoflowers toward methylene blue (MB) and 4-nitrophenol (4-NP) in the presence of NaBH 4 . In addition, the recycling tests showed the high stability and reusability of Cu-LS nanoflowers for at least five cycles with almost constant catalytic performance. This work presents new insights into the fabrication of lignin based catalysts with sustainable biomass derived components to degrade organic pollutants from aqueous solutions efficiently.