Effect of Co2+, Ni2+, Cu2+, or Zn2+ on properties of polyaniline nanoparticles

Uniform polyaniline (PANI) nanoparticles with typical sizes of about 50 nm were electropolymerized on indium tin oxide surfaces in the presence of Co²⁺, Ni²⁺, Cu²⁺, or Zn²⁺. According to shaping theory, we first suggest the reason forming PANI spherical particles. Their conductivity, UV‐vis spectra, FTIR spectra, X‐ray diffraction, and thermogravimetric analysis were investigated. The conductivities and crystallinity of PANI doped with these ions are higher than those of PANI doped with HCl (PANI/HCl). Both UV‐vis absorption spectra and FTIR spectra indicate the interactions between Co²⁺, Ni²⁺, Cu²⁺, or Zn²⁺ and PANI chains. TG analysis also shows that the thermal stability of PANI doped by Co²⁺, Ni²⁺, Cu²⁺, or Zn²⁺ is lower than that of PANI/HCl. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007