Used as a key building block in metal-organic frameworks (MOFs) and covalent organic frameworks (COFs), this compound enables the design of porous materials for gas storage, catalysis, and sensing applications. Its rigid, planar carbazole core with four carboxylic acid groups allows for strong coordination with metal ions, enhancing structural stability. It is also employed in optoelectronic materials due to the inherent charge-transport properties of the carbazole moiety, making it suitable for organic semiconductors and light-emitting devices. Additionally, its extended aromatic structure supports applications in fluorescence-based sensors and dye-sensitized systems.