Synthesis and characterization of porphyrin electrochromic and photovoltaic electropolymers

Photoinduced Charge Separation in Organic–Organic Heterojunctions Based on Porphyrin Electropolymers. Spectral and Time Dependent Surface Photovoltage Study.

“…The porphyrin layers were grown cycling the porphyrin solution in the corresponding potential range until an absorbance of around 0.1 at the Soret band was reached. PEDOT layers were electropolymerized using a 1 mM EDOT solution in DCE containing (TBA)PF 6 . The films were prepared in Pt and ITO electrodes, cycling them in the −0.8/1.5 V range at 100 mV/s for 10 cycles.…”

“…6,16 Both modulated SPV and laserinduced transient photovoltage experiments demonstrated that the photogenerated electrons preferentially traveled in opposite directions, depending on the porphyrin formulation. 6 For the polymer built with free base porphyrin, the electrons were separated toward the internal ITO/polymer interface, and for the Zn(II)-porphyrin polymer, the electrons were separated toward the external surface. In the present work, we conducted, by spectral and time dependent surface photovoltage analysis, a systematic study on the effect of the photoelectrode structures in the generation of photoinduced charge transfer states by porphyrin based electropolymer materials.…”

“…The presence of this hole transport polymer dramatically alters the formation and diffusion process of the photocarriers generated by excitation of the porphyrin films, demonstrating the crucial role of the organic−organic heterojunctions built by electropolymerization in the generation of photovoltaic effects. 6 On the other hand, when the external surface of the porphyrin electropolymers was modified with a layer of a strong electron acceptor (C 60 buckminsterfullerene) the photovoltage signal obtained under similar experimental conditions rose up to near two hundred times, showing that devices formed by combining the here reported porphyrin conducting electropolymers (as light harvesting, electron donor and hole-transport layers) and fullerenes (as electron acceptor and electron transport) could present high efficiency in the conversion of solar radiation into electrical energy, 24 and are promising to be used in the development of new solar energy technologies.…”

Electrochromic properties of electrochemically synthesized porphyrin/3-substituted polythiophene copolymers

“…It can be seen that Por/ 3MT showed more stable activity and color changes during cycles, unlike others. In the copolymer structures electronic delocalization and amount of charge transferred from the porphyrin or zinc/porphyrin donor moiety to the conjugated alkylthiophene side chain acceptor moiety leads to the formation of electron-hole pairs and improves the electrons movement and transition [19,57].…”

“…Porphyrins have excellent electronic and optical properties because of their large π-electron conjugation system [18,19]. However, EC applications of porphyrin based materials are very limited and need further studies.…”