Used as an intermediate in the synthesis of organic semiconductors and optoelectronic materials. Its aldehyde functional groups allow for easy modification in polymerization reactions, making it valuable in the development of conjugated polymers for organic light-emitting diodes (OLEDs) and organic photovoltaics (OPVs). The carbazole core provides good hole-transport properties and thermal stability, enhancing device performance. Commonly employed in donor-acceptor type polymers to tune bandgap and improve charge carrier mobility.