Synthesis And Photovoltaic Performance of Carbazole (Donor) Based Photosensitizers in Dye-Sensitized Solar Cells (DSSC): A Review

Carbazoles are nitrogen-containing aromatic heterocycles, having widespread applications in the field of photovoltaics. Carbazole-based photosensitizers have tunable features for absorption on semi-conductor (tellurium dioxide or zinc oxide) layers to create sufficient push–pull force in the conversion of sunlight into electrical energy, thus presenting as promising heterocyclic donor candidates to be used in dye-sensitized solar cells. For the synthesis of these dyes, various structural designs are available, namely, D-A, D-π-A, D-D-π-A, D-A-π-A, A-π-D-π-A-π-A, and D2-π-A that all involve incorporating carbazole as a donor (D), along with spacer (π-extender) moieties, such as thiophene, phenol, ethynylene, nitromethane, azine, thiadiazole, or acetonitrile. Additionally, acceptors (A) employed in the designs include cyanoacrylic acids, carboxylic acids, malononitrile, rhodanine-3-acetic acid, 4-aminobenzoic acid, or 4-amino salicylic acid. This comprehensive review explores the synthesis and photovoltaic performances of numerous carbazole-based photosensitizers tailored for dye-sensitized solar cells, covering the period of 2019–2023.