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Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. A series of nitrogen-doped polycyclic aromatic mono and dicarboximides (PADI) has been synthesized. Their interest lies in the fact that, unlike other PADI systems, this new family of compounds was synthesized by an innovative procedure that avoids metal-based cross-coupling reactions (Figure 1). In addition, these molecules are able to stabilize multiple redox processes, making them attractive for future electronic devices and batteries. Among the synthesized materials, the semiconductors based solely on naphthalimide units were designed to exhibit electron transporting properties, while the synthesis of the systems based on pyrene and naphthalimide moieties was approached to obtain ambipolar behavior. In our study, we investigated the interplay of different effects such as (i) the type of solubilizing chains (naft-2-4), (ii) the all-acceptor vs donor-acceptor nature of the systems (naft-1 vs naft-2) and (ii) the molecular ordering on the organic field effect transistor (OFET) device response characteristics. Interestingly, we found that all-acceptor systems (naft-2-4) show multiple reduction processes, in which up to tetranion species were stabilized, while the donor-acceptor derivative (naft-1) shows amphoteric redox behavior, in which only up to dianion species were obtained. This lately is in good agreement with the ambipolar mobilities observed for naft-1 in OFETs, while only electron mobilities were registered for naft-2-4 systems. Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech.

Molecular systems have proven to be efficient active materials in electronics, making then suitable substitutes of the inorganic semiconductors used nowadays in electronic devices. For this reason, organic electronics has emerged as a research field with great potential and interest. In this project we have studied, both experimentally and theoretically, two ladder-type compounds functionalized with naphthalimides (Figure 1). The two molecular systems have been implemented in organic field effect transistors (OFETs), to assess their potential as active materials in organic electronics. Both compounds show p-type type mobility, moreover, NDI-TP-Ph-TP material also displays low n-type mobility, presenting a certain ambipolar character. The nature and stability of the charged species involved in the charge transport process have also been studied by spectroelectrochemical experiments. Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech.

A general synthetic strategy toward unsymmetrical hexaazatriphenylene (HAT) derivatives has been developed. The versatility of the strategy is used to synthesize a family of ambipolar donor-acceptor-donor (D-A-D) chromophores, which exhibit broad intramolecular charge transfer (ICT) bands in their solution UV-vis spectra. Tecnología Química y Ambiental

New chiral, soluble binaphthyl derivatives that incorporate stilbenoid dendrons at the 6,6′-positions have been prepared. The synthesis of the new enantiopure dendrimers was performed in a convergent manner by Horner-Wadsworth-Emmons (HWE) reaction of the appropriately functionalized 1,1′-binaphthyl derivative (R)-1 and the appropriate dendrons (R)2nGn-CHO. Different electroactive units were incorporated in the peripheral positions of the dendrons in order to tune both the optical and electrochemical behavior of these systems. Fluorescence measurements on the chiral dendrimers reveal a strong emission with maxima between 409 and 508 nm depending upon the substitution pattern. Finally, the redox properties of the dendrimers were determined by cyclic voltammetry, showing the influence of the functional groups at the peripheral positions of the dendrimer on the redox behavior of these systems.

The covalent linking of acceptor molecules to electron donating conjugated polymer is an approach for the development of new photoactive materials for the fabrication of organic photoelectric conversion devices. With this strategy we have designed a polyalkylthiophene copolymer series containing in the side chain anthraquinone molecules as electron acceptor. The peculiar features of the copolymers are the good processability and the ease in tailoring the content of acceptor moieties. Their potential use as photoactive materials is investigated in terms of the photoinduced charge transfer properties, studied by FTIR photoinduced absorption and Light Induced Electron Spin Resonance spectroscopies. The results indicate the photoinduced electron transfer from the polythiophene backbone to the anthraquinone substituents and its tunability by changing the content of acceptor molecules. The photovoltaic response of these polymers is also discussed.