Photocatalytic One-Pot Conversion of Aldehydes to Esters and Degradation of Rhodamine B Dye Using Mesoporous Graphitic Carbon Nitride

Graphitic carbon nitride (g-C3N4) is a prominent semiconductor material for numerous photocatalytic applications. The mesoporous g-C3N4 (mpg-C3N4), a polymeric metal-free semiconductor proficient photocatalyst with triazine rings, is lightweight and has a high surface area. In this work, we elucidated the role of the mpg-C3N4 photocatalyst for the esterification of substituted benzaldehyde without any additives, a metal-free approach, and under visible light irradiation at room temperature. The mpg-C3N4 has been well characterized by various physicochemical techniques like X-ray diffraction, Fourier-transform infrared, UV-visible spectrophotometry, transmission electron microscopy (TEM), high-resolution TEM, elemental mapping, and the Brunauer-Emmett-Teller surface area. The catalyst characterization revealed that the as-prepared mpg-C3N4 material has a high surface area (97.39 m2/g), porosity, a medium band gap (2.83 eV), and a nanowire-like shape. The mpg-C3N4 properties enhanced the material's photocatalytic activity toward the esterification of substituted benzaldehyde to afford a maximum of 35% conversion with 99% selectivity. A further extension of this work is explored for the organic dye degradation reaction, where it is observed that the materials are stable, sturdy, and reusable for more than eight cycles with a slight loss in activity. This research widens the versatile application of mpg-C3N4 with specific catalytic applications.