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Layer-by-layer thin films of arylenediimides were grown on phosphonate-primed silicon and quartz substrates by the zirconium phosphonate method. The method consists in depositing alternated organic/inorganic layers, where the organic layer was a phosphonate-substituted arylenediimide and the inorganic layer was Zr4+. Heterogeneous films with up to 50 layers, containing different imides, were produced. The building blocks were N,N′-bis(2-phosphonoethyl)pyromellitimide (PPMI), N,N′-bis(2-phosphonoethyl)-1,4,5,8-naphthalenediimide (PNDI) and N,N′-bis(2-phosphonoethyl)-3,4,9,10-perylenediimide (PPDI). Thin films with the sequence PPDI/PNDI, PPDI/PPMI, PNDI/PPMI and PPDI/PNDI/PPMI were produced. Organized film growth was observed by UV–visible–NIR spectroscopy (quartz substrates) and ellipsometry (silicon substrates). AFM images showed that the surface of the films was smooth and uniform. The imides in the films were reduced using sodium dithionite as a reducing agent, generating stable radical anions and dianions of the imides. The following species were detected in the absorption spectra of the reduced films: PPDI−∙, PPDI2−, PNDI−∙, and PNDI2−. Reduction of the imides in the films was rather slow, as compared to homogeneous solutions. When the reduced films were exposed to atmospheric oxygen, reoxidation took place, which was also much slower than in homogeneous solutions. In conclusion, a mix of aromatic imide reduced species, absorbing through the whole visible range, was produced and stabilized in thin films.

The synthesis of three novel phosphonate-substituted aromatic diimides is described: N,N′ -bis(2-phosphonoethyl)pyromellitimide (PPMI), N,N′ -bis(2-phosphonoethyl)-1,4,5,8-naphthalenediimide (PNDI) and N,N′ -bis(2-phosphonoethyl)-3,4,9,10-perylenediimide (PPDI). The imides are water-soluble, allowing spectroscopical studies to be performed in water. PPMI and PNDI exist in the monomeric form in water, but PPDI formed dimers. Self-assembled thin films of the three compounds were grown on phosphonate-primed silicon and quartz substrates by the zirconium phosphonate method. Film growth was followed by ellipsometry (silicon) and ultraviolet/visible absorption spectroscopy (quartz). The films obtained were highly thermally and solvolitically stable for all the three imides, making them excellent candidates for applications in nanotechnological devices.