Nonprecious Metal-Modified Porous Organic Polymers for Enhanced Photocatalytic Degradation

Porous organic polymers (POPs) are promising photocatalyst substrates due to their high surface area, tunable pore size, and functionalization versatility. However, these materials face challenges in structural stability suffering from reversible covalent bonds, rapid electron-hole recombination, and limited scalability in synthesis for photocatalytic water purification. Herein, we demonstrate a cost-effective strategy by depositing nonprecious metal hydroxides (Fe(OH)₂, Ni(OH)₂, and Zn(OH)₂) onto a simple triazine-based POP (PT) to enhance interfacial charge transfer and photocatalytic activity. Remarkably, the Zn(OH)₂-modified PT composite (PT-Zn(OH)₂) achieves 98% degradation of 10 ppm methylene blue within 40 min─a 2.3-fold improvement over pristine PT (42%). Systematic characterization (UV-vis, XPS-VB, electrochemical impedance spectroscopy, and PL) reveals that Zn(OH)₂ deposition optimizes the semiconductor's band structure, reduces charge recombination, and improves interfacial electron-hole separation kinetics. This work highlights the pivotal role of metal hydroxide-POP interfacial engineering in enhancing photocatalysis and provides a scalable, precious-metal-free design for efficient pollutant degradation.