Meso-Tetrakis(4-carboxyphenyl)porphyrin (TCPP) is a porphyrin derivative functionalized with four carboxylic acid groups at the meso positions. This specific functionalization makes it a versatile and widely used building block in materials science. Its primary application is as a key organic linker or precursor for constructing metal-organic frameworks (MOFs) and covalent organic frameworks (COFs). The carboxylic acid groups coordinate with various metal ions (e.g., Zr⁴⁺, Zn²⁺) to form highly porous, crystalline MOFs. These TCPP-based MOFs are extensively researched for applications in photocatalysis (e.g., water splitting, CO₂ reduction), gas storage/separation, and sensing due to the inherent photophysical properties of the porphyrin core. Furthermore, TCPP serves as a functional component in the development of organic semiconductors, dye-sensitized solar cells (DSSCs), and as a photosensitizer in photodynamic therapy (PDT) research. Its ability to be easily metallated further expands its utility in creating functional materials with tailored electronic and catalytic properties.