Enhanced performance of dye-sensitized solar cells via anthocyanin, chlorophyll, benzothiadiazole and diphenylacridine co-sensitizers and amine-based co-adsorbents

Anthocyanin (ANT) and chlorophyll (CHL) natural dyes extracted from blue butterfly pea flowers and spinach leaves and two synthetic metal-free dyes (BIM33 and C1) were evaluated as sensitizers/co-sensitizers in dye-sensitized solar cells (DSSCs). To suppress the possible dye aggregation, triethylamine (TEA) and diethylenetriamine (DETA) were utilized as alternative co-adsorbents to the commonly used chenodeoxycholic acid (CDCA). Furthermore, CHL, BIM33, and C1 were co-sensitized with ANT to achieve panchromatic light absorption and, hence, enhance the photovoltaic performance. Therefore, the power conversion efficiencies (PCEs) of DSSCs based on the dyes were significantly improved from 1.19–5.01 % to 2.39–6.31 % by the co-sensitization and utilization of co-adsorbents. Meanwhile, the efficiencies of DSSCs based on TEA or DETA were superior to those based on CDCA under the same conditions. This study provides effective strategies for improving the performance of DSSCs based on environment-friendly dyes. [Display omitted] •The natural and synthetic metal-free dyes were evaulated as the sensitizers/co-sensitizers for DSSCs.•The photovoltaic performance was improved by the co-sensitization of anthocyanin and chlorophyll.•Diethylenetriamine and triethylamine were utilized as co-adsorbents to suppress aggregation.•The efficiencies of DSSCs were increased from 1.19–5.01 % to 2.39–6.31 % by co-sensitization and co-adsorption.