The role of anchoring groups in ruthenium(II)-bipyridine sensitized p-type semiconductor solar cells—a quantum chemical approach

Abstract

Ru(II)-bipyridine complexes connected with p-type semiconductors (p-SCs) are promising systems for photocatalytic applications such as in dye-sensitised solar cells. The photosensitizer-semiconductor interface—governed by the anchoring group—is of vital importance for the electronic properties of the systems as it determines the long-term stability to the semiconductor surface through its binding ability and also affects the hole injection from the dye to the semiconductor. In this contribution, the role of the anchoring groups in ruthenium(II)-bipyridine sensitized p-type semiconductor solar cells has been addressed by quantum chemical calculations based on density functional theory (DFT) and time-dependent DFT. Both, the interaction of a series of anchoring groups with a NiO surface, as well as several thermodynamical parameter governing the efficiency of a Ru(II)-bipyridine dye coupled to these anchoring groups have been determined and analysed. Based on these calculations, new anchors for p-SC with improved properties are proposed. In addition, the influence of aliphatic spacers and the presence of solvents on the properties of the anchored Ru(II)-bipyridine complexes are thoroughly addressed.

Prediction of strong solvatochromism in a molecular photocatalyst

“…1 Recent years have witnessed an increased understanding of the mechanisms operative in photochemical molecular devices which combine a photosensitizer and a catalyst connected by an electron relay. [2][3][4][5][6][7][8][9] The operation of such molecular devices requires the presence of solvents, and as many molecular complexes are insoluble in aqueous media, often organic solvents are used. 5 Although it is known that the activity of photocatalysts is influenced by the properties of the solvent, 6 it is fair to say that a systematic understanding of this influence is still lacking.…”

A quantum chemical study: thoughtful exploration for optimal donors in Y-type dual donor-based dye sensitizers

“…19,36 Such modifications showed an effective change in the efficiency of several metal-free dye sensitizers as revealed by us as well as different researchers over the ages based on the considerable changes of donors, 26,27,[37][38][39][40][41] spacers [42][43][44][45][46][47] and acceptors. [48][49][50][51][52][53][54] To further increase the efficiency, researchers have been working on the effect of the dual nature of the different components. The additional spacer effect on the dye sensitizer showed an effective change in the efficiency for n-type 20 and p-type 55 dye sensitizers, as shown by our group in recent years.…”

Prediction of Strong Solvatochromism in a Molecular Photocatalyst**

“…[1] Recent years have witnessed an increased understanding of the mechanisms operative in photochemical molecular devices which combine a photosensitizer and a catalyst connected by an electron relay. [2][3][4][5][6][7][8][9] The operation of such molecular devices requires the presence of solvents, and as many molecular complexes are insoluble in aqueous media, often organic solvents are used. [4] Although it is known that the activity of photocatalysts is influenced by the properties of the solvent, [5] it is fair to say that a systematic understanding of this influence is still lacking.…”

“…The efficient direct conversion of sunlight into valuable chemicals is challenging but has the potential to significantly contribute to a carbon‐emission‐free energy economy [1] . Recent years have witnessed an increased understanding of the mechanisms operative in photochemical molecular devices which combine a photosensitizer and a catalyst connected by an electron relay [2–9] . The operation of such molecular devices requires the presence of solvents, and as many molecular complexes are insoluble in aqueous media, often organic solvents are used [4] .…”