Photovoltaic performance and photostability of anthocyanins, isoquinoline alkaloids and betalains as natural sensitizers for DSSCs

• Published in: Solar energy 2018-10, Vol.173, p.34-41
• Main Authors: Güzel, Emre, Arslan, Barış Seçkin, Durmaz, Veysel, Cesur, Mert, Tutar, Ömer Faruk, Sarı, Tuğba, İşleyen, Mehmet, Nebioğlu, Mehmet, Şişman, İlkay
• Format: Article
• Language: English
• Subjects: Absorption spectra; Alkaloid; Alkaloids; Anthocyanin; Anthocyanins; Betalain; Dye-sensitized solar cells; Dyes; Electron transfer; Energy conversion efficiency; Fruits; Irradiation; Photoelectric effect; Photoelectric emission; Photostability; Photovoltaic cells; Photovoltaics; Radiation; Solar cells; Solar energy
• ISSN: 0038-092X; 1471-1257
• DOI: 10.1016/j.solener.2018.07.048

[Display omitted] •Anthocyanin (FBV), alkaloid (RBV) and betalain (FPA, SPA) extracts were used in DSSCs.•Photovoltaic performances are dependent on the molecular structures of the natural dyes.•The DSSC based on SPA shows the highest power conversion efficiency of 3.04%.•FBV sensitized DSSC exhibits excellent stability during solar irradiation for 120 h. Natural dyes extracted from fruit (FBV) and root (RBV) of barberry (Berberis vulgaris) and fruit (FPA) and stalk (SPA) of pokeweed (Phytolacca americana) were used as sensitizers for dye-sensitized solar cells (DSSCs). All the extracts were employed without any modifications, such as purifications or addition of stabilizers. Anthocyanin and isoquinoline alkaloid were identified as the main components for FBV and RBV extracts, respectively, whereas betalain for FPA and SPA extracts. SPA and FPA displayed much broader absorption spectra than the others, which is beneficial to light harvesting capability. When tested in DSSCs, the highest power conversion efficiency (PCE) of 3.04% is obtained by SPA, and this followed by PCEs of 2.97, 2.35 and 2.01% for FPA, RBV and FBV, respectively. The lowest PCE for FBV can be attributed to poor electron transfer ability, which may cause reduced photocurrent and photovoltage. On the other hand, after 120 h of sunlight irradiation, FBV, RBV, FPA and SPA retained the PCE values as 91, 54, 63 and 69% of the initial efficiencies. The moderate photovoltaic performance with good photostability for the anthocyanin extract may favorable for low-cost and environmental-friendly DSSC applications.