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Unveiling the interplay of semiconducting organic molecules with their environment, such as inorganic materials or atmospheric gas, is the first step to designing hybrid devices with tailored optical, electronic or magnetic properties. The present article focuses on a double-decker lutetium phthalocyanine known as an intrinsic semiconducting molecule, holding a Lu ion in its center, sandwiched between two phthalocyanine rings. Carrying out experimental investigations by means of electron spectroscopies, X-ray diffraction and scanning probe microscopies together with advanced ab initio computations, allows us to unveil how this molecule interacts with weakly or highly reactive surfaces. Our studies reveal that a molecule–surface interaction is evidenced when molecules are deposited on bare silicon or on gold surfaces together with a charge transferred from the substrate to the molecule, affecting to a higher extent the lower ring of the molecule. A new packing of the molecules on gold surfaces is proposed: an eclipse configuration in which molecules are flat and parallel to the surface, even for thick films of several hundreds of nanometers. Surprisingly, a robust tolerance of the double-decker phthalocyanine toward oxygen molecules is demonstrated, leading to weak chemisorption of oxygen below 100 K.

Powder samples of Bi_1-xY_xFeO₃ (x = 0, 0.02, 0.05 and 0.1) were prepared by the sol-gel method in this paper. The BiFeO₃ is highly crystallized in rhombohedrally distorted perovskite structure with space group R3c. The double splitting Bragg peaks merged gradually on increasing Y concentration reveal that Y³⁺ ions occupy the Bi site in BiFeO₃. With increasing Y-doping, the magnetization increases in these samples. The results of Mössbauer spectra and X-ray photoelectron spectroscopy indicate that the increase in magnetization comes from the suppression of the modulated spiral spin structure rather than the Fe multiple valences.

This study addresses unreported features for Cu DC-magnetron sputtering on cotton mediating inactivation of Escherichia coli K12 (from now on E. coli). The E. coli inactivation for cotton-Cu samples sputtered for 40 s was attained within 30 min under visible light (1.2 mW/cm²) and within 120 min in the dark. For a longer sputtering time of 180s, the bacterial inactivation kinetics under light was observed within 30 min, as was the case for the 40 s sputtered sample. This suggests that Cu-ionic species play a key role E. coli inactivation. The 40 s sputtered samples present the highest amount of Cu-sites held in exposed positions interacting on the cotton surface (or inside the cotton) with E. coli. Sputtering for 40 s deposited 4.10¹⁶ atoms Cu/cm² (taking ~10¹⁵ atoms/cm Cu per atomic layer) and this was the threshold amount of Cu necessary for complete E. coli inactivation. Cu DC-magnetron sputtering lead to thin metallic semi-transparent grey-brown Cu-coating presenting hydrophobic behavior as determined by contact angle measurements.