High efficiency dye-sensitized solar cells with VOC–JSC trade off eradication by interfacial engineering of the photoanode|electrolyte interface

First application of benzotriazole as a dye additive to dye-sensitized solar cells: electrochemical device characterization

Dye-sensitized solar cell, known as an emergent technology, has been attracted attention around the world. It has been easily produced by a mesoporous semiconductor oxide (SO), with a dye. On the other hand, some unexpected reactions as the back-electron recombination, reducing the solar cell efficiency. The presence of some molecules to act as an oxide passivation might rise up the collection reaction rate, and enhance the photoelectrochemical solar system parameters. The molecule used as a dye additive, must effortlessly adsorb in SO and potentiate the dye deaggregation. This work aims to study the benzotriazole (BTAH) insertion in DSSC with TiO₂, evaluating its capability as a passivator molecule in such PV technology. The electrochemical results showed better electrochemical energy conversion efficiency with lower resistance with BTAH at 2.0 mg mL⁻¹, achieving a j_sc = 9.92 ± 0.26, V_oc = 0.770 ± 0.022, FF = 0.557 ± 0.014, ɳ = 4.26 ± 0.13 with superior electron lifetime and amazing recombination prevention.

A Photoelectrochemical Study of Hybrid Organic and Donor—Acceptor Dyes as Sensitizers for Dye-Sensitized Solar Cells

An investigation on the photoelectrochemical and sensitizing properties of two different hybrid organic dyes, anchored as sensitizers on mesoporous TiO2, in Grätzel solar cells, is presented. Firstly, we studied the absorption properties of the C106 sensitizer, a Ru polypyridine complex, and of the Y123, an organic push and pull dye. In this work, we characterized these two dyes, employing two different electrolytes, with similar experimental condition and device parameters. From the J–V curves and IPCE photo action spectra, we performed an inedited bifacial study based on the comparison of their photovoltaic performances, exploiting several backgrounds (black or white). Among the obtained results from this study, we found the best bifaciality factor of 93% for C106 and the best power conversion efficiency of 12.8% for Y123. These results represent, concerning these two dyes and to the best of our knowledge, some of the highest values in literature.

Hierarchically ordered macroporous TiO2 architecture via self-assembled strategy for environmental remediation

Hierarchical orderd macroporous TiO₂ architecture (HOMTA) was prepared with aid of ethylenediamine (EDA) and investigated the impact of amine molecules on the properties of TiO₂ architecture. The different variation of amine molecules (EDA) leads to tunning the morphology under hydrothermal approach which is confirmed by FESEM and TEM analysis. The XRD and Raman studies confirms the crystal structure of anatase and brookite phase of TiO₂. The surface of the architecture strongly depended on the concentration of EDA which plays a vital role in surface area which is revealed by Brunauer Emmett-Teller (BET) analysis. The obtained HOMTA was employed as photocatalyst and active photoanode in the dye sensitized solar cells (DSSC). The DSSC device exhibits excellent efficiency (η) of 5.27% for the EDA capped TiO₂ (S5) which had high surface area (167.11 m²/g) for better dye loading, whereas the lower concentration of EDA capped TiO₂ (S1, S2, S3 and S4) resulted the efficiency of 2.14, 3.90, 3.25 and 4.37%, respectively. The efficiency of photocatlysis degradation of the prepared samples (S1, S2, S3, S4 and S5) was 94.8, 90.47, 91.41, 91.32 and 93.75% under light source. The excellent photocatalysis property was achieved by S5 within 6 min due to high surface area which inducing more active site.