Asymmetric Dual Anchoring Sensitizers/Cosensitizers for Dye Sensitized Solar Cell Application: An Insight into Various Fundamental Processes inside the Cell

Abstract

To study the various fundamental processes occurring inside the dye sensitized solar cell (DSSC), we have fabricated devices employing newly synthesized diphenylamine-based organic dyes with A-D-π-A configuration, carrying four different anchoring groups, namely, cyanoacetic acid (DDC), rhodanine acetic acid (DDR), 4-hydrazinylbenzoic acid (DDH), and barbituric acid (DDB), as effective sensitizers/cosensitizers. In the present work, all the bianchoring dyes were subjected to photophysical, electrochemical, thermodynamic, photoelectrochemical, and theoretical studies. All of them displayed characteristic λabs and λemi in the range of 415–480 and 570–680 nm, respectively. Their optical and electrochemical band gaps were calculated to be in the order of 2.1 to 2.3 eV. The calculated driving forces for electron injection (ΔG inj), recombination (ΔG inj), and regeneration (ΔG reg) processes were found to be negative, showing the feasibility of these processes, while their DFT studies clearly indicated the directional flow of electrons within the dye in the cell. The devices with DDC as sensitizer displayed the highest conversion efficiency of 2.53%, whereas DDB exhibited the maximum of 7.69% when employed as a cosensitizer along with Ru (II) based HD-2 dye. Finally, EIS circuit fitting was carried out in order to obtain different interface resistance values to study the fundamental processes of energy conversion.

Optimizing the Cosensitization Effect of SQ02 Dye on BP-2 Dye-Sensitized Solar Cells: A Computational Quantum Chemical Study

“…E 0−0 is the electronic vertical transition energy at λ max . The efficiency of regeneration process can be quantitatively expressed by its corresponding free energies driving force of regeneration (ΔG reg ), according to the following equation: 8,61…”

“…) is the oxidation potential of the electrolyte (−4.8 eV). 62,63 Moreover, in order to examine the competing loss pathway (dark current), namely the recombination reaction of the injected electrons in CB of TiO 2 with I 3 − ions in the electrolyte solution, the free energy driving forces of recombination reaction was estimated through the following equation: 8,64…”

Synthesis and Computational Characterization of Organic UV-Dyes for Cosensitization of Transparent Dye-Sensitized Solar Cells

“… is the reduction potential of the CB of TiO 2 , in which the experimental value −4.00 eV [ 58 ] (vs. vacuum) was used and is the electronic vertical transition energy at . The driving force for efficiency of dye regeneration (Δ G reg ) is calculated via the following equation [ 59 , 60 ]: …”

“…In which is the oxidation potential of the electrolyte (−4.8 eV) [ 61 ]. Furthermore, the competing loss pathway (dark current), namely the recombination reaction of the injected electrons in CB of TiO 2 with I 3 − ions in the electrolyte solution can be assessed using the free energies driving force of recombination reaction according to the following equation [ 59 , 62 ]: …”

The influence of three diphenylpyran isomer co-sensitizers with different sterical structures on N719-based dye sensitized solar cells

“…As the red-shi extent follows the trend of the planarity of the three kind of molecules, this bathochromic effect can be ascribed to the dye molecular formation of J aggregates on the TiO 2 surface. 30 The DM molecule with the most steric conguration gets less red-shied, suggesting its less aggregation on TiO 2 compared to the other two dyes. The redox potentials of the dyes were measured in DMF solution by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) in the presence of 0.1 mol L À1 tetrabutylammonium hexauorophosphate as the supporting electrolyte using a scan rate of 100 mV s À1 and are a Angle between the cyanoacrylic acid and the adjoining phenyl ring 2. b Distance between the oxygen of the carbonyl group and the hydrogen of hydroxyl group.…”