Push‐Pull N‐Annulated Perylene‐Based Sensitizers for Dye‐Sensitized Solar Cells: Theoretical Property Tuning by DFT/TDDFT

Abstract

We evaluate the effects of donor and π‐linker moieties on power‐conversion efficiency for a series of push‐pull type, N‐annulated perylene dyes for dye‐sensitized solar cells. Triphenylamine and diphenylamine are used as electron donors. We investigate the structural, optical, and electronic properties of dyes by performing density functional theory (DFT) calculations at the B3LYP level, using the 6‐311G(d,p) basis set. Electronic absorption wavelengths were investigated using time dependent DFT (TD‐DFT) calculations on M062x/6‐311G(d,p) in THF. Our calculated results reveal that the diphenylamine (DPA) donor provides a small dihedral angle between diphenylamine and the perylene core, resulting in a red‐shifted absorption spectrum. Introduction of an O‐methoxy substituent into diphenylamine improves its donor properties, red‐shifts the absorption wavelength, and increases the dipole moment, indicating increased intramolecular charge transfer in the O‐methoxy substituted dye. Incorporation of a C‐C triple bond in linker extends the π‐conjugation system and decreases the dihedral angle between N‐annulated perylene and cyanoacrylic acid; the dye adopts a planar structure, causing a red‐shift in the absorption spectrum. Our results demonstrate that use of computational design can to help the experimentalist for out looking future developments to identify push‐pull perylene sensitizers for highly efficient solar cells.

Design and Synthesis of New Bithiophene Based Planar AIE Red Light Emitters: A Detailed Theoretical and Experimental Analysis**

“…The bandgap tuning in a system aiming at one specific emission wavelength is made possible by mere chemical substitution of appropriate electrondonating/withdrawing groups and is gaining interest in the field. [2][3][4][5][6][7] In general, a planar conventional organic luminescent system exhibits a good emission in a non-aggregated state than their aggregated state. [6,[8][9][10] Weak emissions in a planar molecule may be attributed to the presence of intense π-π stacking between the lattice planes.…”

Schiff Bases and Their Complexes in Organic Light Emitting Diode Application

“…26 Strategic architecture of desirable highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels in the active emitting layer is important for the rapid transfer of electrons and holes to the EML. [27][28][29][30][31] Functional metal-organic materials are an evolving class of luminophores as they include the benefits of both organic dyes, which are color-tunable with strong emission and transition-metal-based emitters with large Stokes shifts and high photostability. 32 These coordination complexes of organic molecules have been widely investigated for the development of electroluminescent devices that exhibit intense and bright fluorescence emission spanning the entire visible region from violet to red with high quantum efficiencies.…”

Design, Synthesis and Characterization of N‐Substituted Heteroaromatics: DFT‐Studies and Organic Light Emitting Device Application

“…Design strategies of active light emitters must result in the system possessing an optimal highest occupied and lowest unoccupied orbital energy levels to ease the charge injection and transport into the emissive layer. [11][12][13][14][15][16][17] Research development in this field has shown significant progress in the past few decades by a generation of different color emission, sweeping over the entire visible spectrum. [18][19][20][21][22][23][24][25][26][27] Despite steady progress, the efficient design of blue monochromatic luminophores functioning as active material in OLEDs remains a serious challenge.…”

“…Precise bandgap engineering of an organic molecule achieved by various chemical routes has proven successful in the generation of desired fluorescent color emission. Design strategies of active light emitters must result in the system possessing an optimal highest occupied and lowest unoccupied orbital energy levels to ease the charge injection and transport into the emissive layer . Research development in this field has shown significant progress in the past few decades by a generation of different color emission, sweeping over the entire visible spectrum .…”