Electrochemistry and Electropolymerization of Znic Porphyrins Bearing Aromatic substituents.

[[abstract]]在本論文中，我們利用電化學方法探討紫質苯環於 ortho-、meta-、para- 位置接有長碳鏈烷類取代基紫質光敏劑之氧化還原電位探討；結果顯示，在紫質苯環 ortho- 位置上修飾長碳鏈烷類取代基的氧化還原電位比在 meta-、para- 位置上修飾有長碳鏈較往負電位位移；上述現象可能造成紫質化合物的 LUMO 能階提高，當使用這些紫質化合物作為染料敏化太陽能電池內的光敏劑時，有機會使得開路電壓值也相對提高。當染料吸收太陽光被激發後，有利於電子注入到 TiO2 的導帶上，希望藉此驅動力可以提高染料敏化太陽能電池的光電效能。我們也探討在紫質大環上修飾蔥類、芘類等取代基的紫質化合物氧化還原的電位變化，這些紫質化合物的氧化還原電位相當接近，表示 LUMO、HOMO 能階值可能也相當接近，在紫質苯環上修飾有不同取代基的紫質化合物對電化學電位的影響不大。 我們也於紫質大環上修飾苯胺取代基，並探討其電聚合反應。實驗結果顯示代號APE-3 及 APE-5 的紫質化合物皆能在 Pt、GCE、Au 及 ITO上聚合成膜，並可利用紫外光-可見光譜儀觀察聚合在 ITO上的膜，可以觀察到紫質苯環結構未受到改變。此外，也利用 SEM/EDS 觀察在 ITO 上紫質薄膜表面型態及組成。[[abstract]]In this work, we studied the electrochemistry of porohyrins with long alkoxyl chains attached at the ortho- and meta-, para- positions of the phenyl group by CV and DPV. The CV results indicate that the redox potentials of the porohyrins with long alkoxyl chains attached at the ortho- position of the phenyl groups are more negative-shifted than that of those with long alkoxyl chains attached at meta- and para- positions of the phenyl group. This suggests that the porohyrins with long alkoxyl chains attached at the ortho- position of the phenyl group should have a higher LUMO energy level and hence the Voc. When dye is excited, the electron injection should be more favorable than the porohyrins with long alkoxyl chains attached at the meta- and para- position of the phenyl groups. As a result, enhanced photovoltaic performance of the corresponding devices is expected. We also discussed the redox potentials change of porphyrins attached by pyrene or anthracene substituents. The porphyrins with pyrene or anthracene substituents have similar redox potentials and energy gaps. Porphyrins with aniline substituent were also studied for their electropolymerization. Electrochemical and UV-visible showed that APE-3 and APE-5 porphyrins were electropolymerized onto Pt, GCE, Au and indium tin oxide (ITO) surfaces without significantly changing porphyrin structures. SEM/EDS were used to observe the ITO and to provide the porphyrin film composition.[[note]]碩