In Situ B‐ <scp>gC</scp> ₃ N ₄ Mixed Matrix Membrane Strategy for Enhanced Dye Removal: A Pathway to Exceptional Water Purification Efficiency

ABSTRACT The in situ synthesized boron‐doped graphitic carbon nitride (B‐gC 3 N 4 ) composite exhibits significant potential as an advanced and efficient solution for wastewater treatment. This study demonstrates that incorporating B‐gC 3 N 4 into polysulfone (Psf) membranes offers a promising approach to improving the efficiency of organic dye removal from water. The B‐gC 3 N 4 was synthesized through a simple thermal polymerization method with in situ boron doping. The fabrication and performance of B‐gC 3 N 4 composite membranes with 2.5, 5, and 7.5 wt.% were examined. Performance evaluations focused on the removal efficiency of congo red (CR) (97.95%), evans blue (EVB) (98.99%), eriochrome black tea (EBT) (94.46%), alcian blue (AB) (&gt; 99.9%), malachite green (MG) (&gt; 99%) and methyl blue (MB) (&gt; 99%) respectively. However, the membrane showed excellent antifouling behavior by showing a flux recovery ratio of 89.4% with the rejection of bovine serum albumin (BSA) observed at 89.85%. A long‐term stability study using an optimum membrane of 5 wt% B‐gC 3 N 4 showed a consistent rejection rate of 94.57% over 48 h and a flux of 83.87 L/m 2 /h for CR. The improved performance is ascribed to the amplified surface area and improved hydrophilicity of the B‐gC 3 N 4 component. By demonstrating outstanding flux performance, B‐gC 3 N 4 /Psf membranes offer an active and justifiable solution for the elimination of organic dyes from contaminated water.