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Conductive organic materials
Organic conductive materials can be devided in p-type and n-type materials. The main difference is the electric charge of their charge carrier: p-type materials are positive charges conductors and n-type materials are negative charges conductors. Furthermore, organic conductive materials can be grouped into two main classes: conductive molecules and conductive polymers.

p-type materials
P-type materials have been extensively studied in the past. Among the numerous p-type polymeric materials there are polypirrole, polythiophene, polyaniline and pedot.

n-type materials
Even if electronic devices requires both p-type and n-type materials, in the past the research has been mainly focussed on the development of p-type materials. This disproportion is mainly due to the lack of commercially available n-type materials and their poor stability which greatly affects their processability and their study. The rather poor atmospheric stability of n-type materials is directly linked to their high LUMO level. For this reasons many n-type materials are conjugated systems functionalized with electron-withdrawing functional groups. Among n-type molecular materials there are: perylene and naphtalene based materials and fullerenes. Among n-type polymeric materials there are p-phenylene vinylene derived polymers, organometallic coordination polymers and P(NDI2OD-T2) derived polymers.

Perylene and Naphtalene derived materials
Naphthalene diimide (NDI) and Perylene bisimide (PDI) derive from naphtalene dianhydride (NDA) perylene dianhydride (PDA), respectively. NDA and PDA can be functionalized with two side groups that provide increased solubility in organic solvents and crystallization tailoring. As reported by Shukla, D. et al., the π molecular orbital has nodes in the position of the two nitrogen atoms and this allows to change side substituents without drastically modifying the electronic structure. This characteristic, combined with their easy single-step synthesis from commercially available NDA and PDA, makes NDI and PDI materials very popular: modifications in side chain lenght, ramifications, polarity and intramolecular binding have been explored. Another class of naphtalene-derived molecules are the naphtodithiophenediimide (NDTI) molecules which are core-extended NDI derivatives characterized buy a reduced steric hinderance and an increased solubility in common organic solvents. Furthermore, NDTI molecules are more customizable since they can be easily functionalized both on the nitrogen imide atoms (where solubilizing alkyl chains are usually inserted) and on the α thiophene positions (where it is possible to add electron-withdrawing groups to further tune their electronic properties).

Reilly T. H. et al. have created a water soluble PDI with a remarkable electrical conductivity of 10-3 S cm-1. Russ B. et al. have functionalized PDI molecules with different lenght alkyl chains tethering an amine group (acting as an intrinsic dopant) to the perylene core and were able to obtain a dramatic increase in electrical conductivity, up to 0.5 S cm-1.