Self-assembly of phthalocyanine and polyacrylic acid composite multilayers on cellulose nanofibers

In this study, a novel nanocomposite multilayers was deposited on the electrospun nanofibrous mats by an electrostatic layer-by-layer (LBL) self-assembly technique. The positively charged water-insoluble 2,9,16,23-tetraaminophthalocyanine copper (CuTaPc) and the negatively charged water-soluble poly(acrylic acid) (PAA) were alternately deposited on the surface of negatively charged nanofibrous cellulose mats. The cationic CuTaPc was synthesized and characterized by UV–Vis and Fourier transform infrared (FT-IR) spectroscopy. The template nanofibrous cellulose mats were obtained from the alkaline hydrolysis of electrospun nanofibrous cellulose acetate mats. The resultant nanofibrous mats were characterized by scanning electron microscopy (SEM) and FT-IR spectroscopy. The SEM images showed that the composite LBL structured films were homogeneously deposited on the surface of the nanofibers. The diameters of nanofibers increased with the number of deposition bilayers. The average thickness of each CuTaPc/PAA bilayer is about 10 nm. Additionally, the FT-IR spectra results also indicated that the CuTaPc and PAA were coated on the nanofibrous cellulose mats.