Hologram quantitative structure-activity relationship guided in silicon molecular design of phenothiazine dye sensitizers for dye-sensitized solar cells

Abstract

Hologram quantitative structure–activity relationship (HQSAR) method was successfully introduced into the structure-performance study on the phenothiazine dye sensitizers of dye-sensitized solar cells. A total of 79 phenothiazine derivatives were investigated to build the HQSAR model of power conversion efficiency. The fragment parameters of the established optimal HQSAR model are fragment size: “4 ∼ 7”, hologram length: “353”, and fragment distinction: “bonds, connections, chirality, donor and acceptor atoms”. The predictive performance of the HQSAR model was evaluated with external test set validation and leave-one-out cross-validation. The validation results demonstrate that the developed model possesses high prediction ability and stability. The molecular contribution map of this model was analyzed to reveal the key structures and modification positions for improving the power conversion efficiency, and was used to guide the molecular design of high performance dye sensitizers. The theoretical prediction result of several literature reported phenothiazine compounds indicates that the developed model is an effective and important guidance to the molecular design of dye sensitizers. Therefore, several new phenothiazine derivatives with theoretically improved power conversion efficiency were designed by the proposed HQSAR-based strategy.