Molecular design of near-IR harvesting unsymmetrical squaraine dyes

Sanghoon Kim; Gopal K Mor; Maggie Paulose; Oomman K Varghese; Chul Baik; Craig A Grimes

doi:10.1021/la101257b

Molecular design of near-IR harvesting unsymmetrical squaraine dyes

Langmuir. 2010 Aug 17;26(16):13486-92. doi: 10.1021/la101257b.

Authors

Sanghoon Kim¹, Gopal K Mor, Maggie Paulose, Oomman K Varghese, Chul Baik, Craig A Grimes

Affiliation

¹ Department of Electrical and Computer Engineering, Texas Tech University, Lubbock, Texas 79409, USA.

PMID: 20695595
DOI: 10.1021/la101257b

Abstract

The functionalized unsymmetrical benzothiazole squaraine organic sensitizers 5-carboxy-2-({3-[(3-hexylbenzothiazol-2(3H)-ylidene)methyl]-2-hydroxy-4-oxo-2-cyclobuten-1-ylidene}methyl)-1-hexyl-3,3-dimethyl-3H-indolium (hereafter named as SK-11) and 5-carboxy-2-({3-[(3-hexyl-5-methoxybenzothiazol-2(3H)-ylidene)methyl]-2-hydroxy-4-oxo-2-cyclobuten-1-ylidene}methyl)-1-hexyl-3,3-dimethyl-3H-indolium (coded as SK-12) are designed and developed to observe an intense and wider absorption band in the red/NIR wavelength region. DFT/TDDFT calculations have been performed on the two unsymmetrical squaraine sensitizers to gain insight into their electronic and optical properties. The utility of these dyes in solid state dye sensitized solar cells (SS-DSSCs) is demonstrated.