Preparation, luminescent, structural and electrical properties of Langmuir-Blodgett films of new organomercurial acetylide complex/heteropolyoxometalate hybrid composites

A new family of organometallic/inorganic nanohybrid Langmuir-Blodgett (LB) films consisting of rigid-rod organomercury acetylide complex (OMA) as the π-conjugated organometallic composite and heteropolyacid salts MPA (MPA = K₃PMo₁₂O₄₀, K₅BW₁₂O₄₀, Na₅IMo₆O₆₂) of the Keggin and Anderson structures as the inorganic composite, were prepared and characterized by π−A isotherms, UV−Vis absorption spectra, fluorescence spectra, scanning tunneling microscopy, atomic force microscopy imaging and low-angle X-ray diffraction. Our experimental results indicate that steady Langmuir and LB films are formed in pure water and heteropolyacid salt subphases. Luminescence spectra of hybrid LB films show that MPA can quench the emission of OMA to some extent. These alkynylmercury(II) based LB films display interesting electrical conductivity behavior. They all show decent electrical conductivity, and the tunneling current amounts to ±100 nA when the voltage is set at ±3 ∼ ±5 V.