Synthesis and characterization of a conjugated porphyrin dyad entangled with carboxyl functionalized benzimidazolium: an efficient metal free sensitizer for DSSCs

Abstract

Synthesis of a novel metal free porphyrin dyad with excellent electronic coupling and anti-aggregating stability via strong anchoring to semiconductor through six carboxyl groups exhibiting 6.9% PCE in a truly energy generating DSSC.

Visible Light Mediated Heck Coupling of Inactivated Aryl Fluoride/Chloride Over a Sulfonic Acid Functionalized, Melamine‐based Metal‐free Porphyrin Photocatalyst

“…where a ‐ absorption coefficient of the photo‐catalyst, hν‐photon energy, E g ‐ bandgap energy of the photo‐catalyst, and n takes the index values of 2, 3, 1/2, and 3/2 for direct allowed, direct forbidden, indirect allowed and indirect forbidden types of transition respectively. By rearranging equation (1) to an equation of a line, it follows that for a direct bandgap (n=2), the plot of (ahν) 2 vs. hn show a linear behaviour beyond an edge, the extrapolation of the linear portion to the x‐axis thus gives the magnitude of the direct allowed type band gap of the catalyst [69] . Accordingly, Figure 3 shows the Tauc plot, exhibiting the optical band gap energy of 1.44 eV.…”

“…By rearranging equation ( 1) to an equation of a line, it follows that for a direct bandgap (n = 2), the plot of (ahν) 2 vs. hn show a linear behaviour beyond an edge, the extrapolation of the linear portion to the x-axis thus gives the magnitude of the direct allowed type band gap of the catalyst. [69] Accordingly, Figure 3 shows the Tauc plot, exhibiting the optical band gap energy of 1.44 eV. The presence of an optimal bandgap suggests that the photocatalyst does possess strong absorption characteristics in the visible-NIR region so that it can accelerate the photocatalytic activity even at normal temperature.…”

Visible‐Light Aided C−H activation: Metal/Base‐Free Generation of C−C bonds using Porphyrin Photocatalyst

“…The CPDCFBM has been prepared following the protocol reported in our previous literature. [43] The preparation of CPDCFBM from intermediate (C), 3 A is displayed in scheme 1, while a detailed stepwise synthesis and characterization of all the intermediates are provided in the Supporting Information (SI). Typically, CPDCFBM photocatalyst was synthesized by refluxing precursor 2 C, 3 A and Pyrrole in 6 : 1 : 8 (mmol) concentration in AcOH for 40 minutes at 80 °C.…”

“…The dye exhibited an optimal bandgap of 1.7 eV with suitable frontiers energies (HOMO À 5.841 and LUMO energy À 4.066 eV Vs, vacuum). [43] In the present study, we explore the ability of the metal free…”

Metal Free Porphyrin Photocatalyst Comprising Ionic Liquid with Electron Donor Acceptor Moiety for Visible Light Assisted Oxidative Amination

“…To the best our knowledge, there are no reports about the synthesis of metal free porphyrin with donor acceptor moieties, entangled with ionic liquid and Brønsted acid functionalities, for transformation of primary amines to imines under visible light irradiations. [71] In line with this progress, [72] our group has synthesized porphyrin photocatalysts [73] and successfully utilized for the conversion of biomass derived chemicals [74] to value added compounds, [75] organic transformations [76] and application in dye sensitized solar cell. [77] Herein, we herein report the design, synthesis and characterization of metal free porphyrin photocatalyst with electron donor acceptor moiety for visible light assisted oxidative amination.…”