ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

The effect of bis-carboxylic groups of squarylium dyes on the efficiency of dye-sensitized solar cells

Sultan A. Al-horaibi, Eman M. Garoon, Narendra A. Bhise, Suresh T. Gaikwad, and Anjali S. Rajbhoj

Department of Chemistry, Dr. Babasaheb Ambedkar Marathwada University, Aurangabad, India

E-mail: anjali.rajbhoj@gmail.com

Received: 21 May 2019  Accepted: 23 October 2019

Abstract:

Symmetric squarylium dye (SQIND1) with bi-carboxylic groups has been synthesized and photoelectrochemical properties have been studied in comparison with its non-functionalized analog groups (SQIND2). The experimental results showed that the introduction of anchor carboxylic groups in SQIND1 sensitizer provides a more intimate contact with nanoparticles TiO₂ which increases the number of charge carriers transferred from the SQIND1 to the semiconductor. The theoretical calculations and absorbance results show that the electron density of LUMO of SQIND1 is delocalized in the whole chromophore, leading to strong electronic coupling between SQIND1 sensitizer and conducting band of TiO₂, resulting in improved dye-sensitized solar cell efficiency compared to SQIND2. Hence, the SQIND1 sensitized exhibit better photovoltaic performance. Although, the absence of any linker groups in the SQIND1, then SQIND1 was perfect efficiently sensitized on porous TiO₂ with the long UV–Vis and NIR region up to 800 nm of the spectrum and showed higher remarkable performance of values, such as η of 3.3%, a J_sc of 7.6 mA/cm², a V_oc of 0.59, and FF of 0.73.

Keywords: Dye-sensitized solar cell; Symmetric squarylium dyes; Cyclic voltammetry; DFT; Photoelectrochemical properties

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-019-00978-5

Chemical Papers 74 (6) 1769–1778 (2020)