The influence of microbial sources on astaxanthin implementation as sensitiz‐ er in dye sensitized solar cells (DSSCs).

In the context of increasing the use of sustainable materials derived from renewable, non-toxic, and biocom- patible sources, dyes obtained from microorganisms have garnered significant interest, particularly for clean energy applications. This study presents a novel comparison of astaxanthin produced from three different mi- crobial sources for dye-sensitized solar cells (DSSCs) to evaluate their photovoltaic performance. Comprehensive characterization using multiple analytical techniques (HPLC-DAD-APCI-MS, UV–vis spectroscopy, scanning electron microscopy (SEM), IV measurements, and electrochemical impedance spectroscopy (EIS)) were carried out on pigments extracted from the microalga Haematococcus pluvialis, the yeast Phaffia rhodozyma, and the bacterium Paracoccus carotinifaciens to highlight the structural differences that influence the dyes’ photo- electrochemical behavior. The results show that the DSSC based on the extract from Paracoccus carotinifaciens demonstrated the highest efficiency, recording a short-circuit current density (Jsc) of 2.86 mA/cm2, an open- circuit voltage (Voc) of 0.419 V, a fill factor (FF) of 0.3, and a power conversion efficiency (PCE) of 0.36 %.