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.