Efficient and stable monolithic microreactor with Ag/AgCl photocatalysts coated on polydopamine modified melamine sponge for photocatalytic water purification

The advantages of photocatalytic microreactors, including large specific surface area, rapid mass transfer, continuous flow operation capability and low safety hazards promote the application in the field of water purification., We propose a monolithic microreactor for depositing Ag/AgCl photocatalysts on the surface of the polydopamine(PDA) -modified melamine sponge(MS) backbone. The experimental results revealed that the monolithic microreactor enables to completely degrade methylene blue(MB) under visible light irradiation within 10 min and can photodegrade 250 L m-2 of MB per hour. Moreover, we confirmed that the lifetime of MS/PDA/Ag/AgCl can be extended by a simple in situ chemical recovery method, thus making the monolithic microreactor reusable for a long time. In conclusion, the prepared monolithic microreactor has high efficiency of photodegradation, high throughput and reusability, and displays broad application prospects in the field of photocatalytic water purification.