Lead phthalocyanine modified carbon nanotubes with enhanced NH3 sensing performance

Two kinds of novel carbon nanotubes hybrids were prepared by noncovalent hybridization of the acidified multi wall carbon nanotubes (MWCNT-COOH) and single wall carbon nanotubes (SWCNT-COOH) with lead 2,9,16,23-tetra-iso-pentyloxyphthalocyanine (PbPc) and characterized by FTIR, absorption spectra and scanning electron microscopy. The results revealed that the PbPc derivatives had been successfully anchored on the surface of nanotubes through π–π stacking. The gas sensing behaviors of the MWCNT-COOH, PbPc/MWCNT-COOH, SWCNT-COOH and PbPc/SWCNT-COOH films were investigated with respect to NH3 at room temperature. The synergetic behavior between PbPc and CNTs allows an excellent sensitivity to NH3. We present the advantages of combining metallophthalocyanine (MPc) with CNTs in enhancing the gas sensing properties of the final product, and pave a new way for the application of MPc/CNTs hybrids in the gas sensing field.