Bioinspired polydopamine-layered double hydroxide nanocomposites: controlled synthesis and multifunctional performance

Abstract

A biomimetic multifunctional nanocomposite was synthesized, in which a polydopamine (PDA) thin film was deposited on a layered double hydroxide (LDH) through an interlayer polymerization. Kinetic controlled polymerization of dopamine (DA) in a basic buffer solution under a nitrogen atmosphere provided a synthetic pathway for the nanostructured PDA/LDH composites without polymer agglomerates, allowing the crystallinity of the pristine LDH nanoparticles to be maintained. The contraction of the interlayer spacing for the (00l) reflection of PDA/LDH nanocomposites demonstrated intercalation of PDA into the LDH interlayer space. The catalytic activity of the PDA/LDH nanocomposites was evaluated by observing the reduction of p-nitrophenol in the presence of NaBH₄, in which the PDA layer acts as a protection layer against surface contamination of the nanocomposites. Electrochemical capacitive performance was also observed due to the strong adhesion of PDA to the Ni foam electrode. The nanostructure of the PDA/LDH nanocomposites induced by interlayer polymerization drove the incorporative organic–inorganic functional materials with blocked surfaces and improved the electrochemical properties, providing a reliable synthetic pathway to prepare multifunctional nanohybrid materials.