Opp‐Dibenzoporphyrins as a Light‐Harvester for Dye‐Sensitized Solar Cells

Abstract

New opp-dibenzoporphyrins were prepared in a concise method that was based on a Pd(0)-catalyzed cascade reaction. These porphyrins, which contained carboxylic-acid linker groups on benzene rings that were fused to the porphyrin at their β,β'-positions, were examined as sensitizers for dye-sensitized solar cells for the first time. Whereas all of the porphyrins showed solar-energy-to-electricity conversion, an opp-dibenzoporphyrin with conjugated carboxylic-acid linkers displayed the highest conversion efficiency and an exceptionally high J(sc) value. Cyclic voltammetry of these porphyrins suggested that the fusion of two aromatic benzene rings onto the periphery of the porphyrin lowered the HOMO-LUMO energy gap; the incorporation of a conjugated carboxylic-acid linker group decreased the HOMO-LUMO gap even further. These CV data are consistent with DFT calculations for these porphyrins and agree well with the UV/Vis absorption- and fluorescence spectra of these porphyrins.

Monobenzoporphyrins as Sensitizers for Dye‐Sensitized Solar Cells: Observation of Significant Spacer‐Group Effect

“…Our group has been engaged in the development of concise and versatile synthetic methods to access β‐functionalized π‐extended porphyrins . In previous work, we showed that opp ‐dibenzoporphyrins with pull–pull structures could convert solar energy to electricity with moderate efficiencies ( η =1.5–3.1 %) . In this work, we present the synthesis, characterization, and evaluation of a series of monobenzoporphyrins as sensitizers in DSSCs.…”

The importance of various anchoring groups attached on porphyrins as potential dyes for DSSC applications

“…36) were synthesized through a Pd 0 -catalyzed cascade reaction. 111 These opp-dibenzoporphyrins (112)(113)(114)(115)(116) were evaluated for the rst time as light harvesters for dye-sensitized solar cells. These porphyrins displayed moderate solar energy-to-electricity conversion efficiencies of 1.54-3.14%.…”

Strategic Synthetic Approaches to Porphyrin-Based Artificial Light-Harvesting Systems for Solar Energy Utilization

“…118 These opp-dibenzoporphyrins (72)(73)(74)(75)(76) were evaluated for the first time as a light harvester for dye-sensitized solar cells. These porphyrins displayed moderate solar energy-to-electricity conversion efficiencies of 1.54%-3.14%.…”

“…The higher efficiency of 118 than that of 117 was attributed to the longer electron lifetime and higher amount of dye adsorption onto the TiO2 surface. The efficiency was found to improve up to 4.83% (117) and 6.07% (118) when CDCA was incorporated in the dye solution. The electrochemical impedance data indicated that the electron lifetime was improved by the co-adsorption of CDCA, which was attributed to the improvement in both V oc and J sc .…”

“…141 A stepwise approach for co-sensitization of the zinc porphyrin sensitizer (118) with symmetrical BF 2 -azopyrrole dye (119) for DSSCs was described. With this approach, the co-sensitized 118 + 119 based DSSC showed both J sc and V oc significantly enhanced in relation to their individual sensitized DSSCs.…”