Organic acids on the fabrication of sol–gel lead zirconate titanate fibers

Lead zirconate titanate (PZT, 53/47) fibers are prepared by sol–gel method using organic acids – acrylic and methacrylic acid – to modify the precursors. The macroscopic properties, molecular structure, crystallization behaviour and microstructure of the fibers are investigated as a function of the content and type of acid. Organic acids produce long gel and ceramic fibers, due to the beneficial effect of the long polymeric chains that are generated in the precursor gel. However the longest, strongest, densest and with the highest homogeneity fibers are obtained when acrylic acid is used. The linear shape of the molecular structure of acrylic acid, together with a lower content of organic species to be released, is favourable to the preparation of round and crack free PZT fibers, when acrylic acid is used.