ELECTROCHROMIC AND GAS-ADSORPTION PROPERTIES OF LANGMUIR-BLODGETT-FILMS OF LUTETIUM BISPHTHALOCYANINE COMPLEXES

The electrochromic behaviour, spectroscopic properties and gas chemiso rption of ultra thin films of lutetium octa-4-phenyldiphthalocyanine ( LuPc2Ph), and the lutetium octa-3-bromo-octa-5-tert-butylphthalocyanin e (LUPC2tBr) are reported. Electrochromism was observed for Langmuir-B lodgett (LB) and films cast onto indium tin oxide (ITO) coated glass e lectrodes in aqueous KClO4 solution. Mixed LB films supported on ITO g lass electrodes were more stable to repetitive cycling than cast films . Films of LuPc2Ph and LUPc2tBr were sensitive to electron-acceptor ga ses as observed by the changes in the electronic absorption spectra an d the surface-enhanced resonance Raman scattering (SERRS) spectra. The presence of electron-withdrawing bromine atoms in the phthalocyanine ring increased the rate of desorption for chemisorbed electron-accepto r molecules.