Breaking the cost barrier: polydopamine@NixCo100-x nanotubes as efficient photocatalysts for organic pollutant degradation

The synthesis of efficient and affordable catalysts for photocatalysis has long been a key objective in environmental materials research, particularly in the development of nanocatalysts doped with nanometals. Unfortunately, the high cost of noble metal nanocatalysts has hindered large-scale applications. To overcome this challenge, a novel low-cost approach has been developed for the preparation of polydopamine (PDA)@NixCo100-x nanotubes, using an in-situ reduction strategy under mild reaction conditions in this study. The resulting nanotubes contain active NiCo nanoparticles encapsulated in the inner wall, exhibiting excellent photocatalytic performance along with magnetic properties. The optimal PDA@Ni25Co75 nanotubes achieved 99.3% photocatalytic degradation in 10 min and 95.7% in 15 min for azo dye methyl orange and 4-nitro phenol, respectively, outperforming the previous materials reported in the literature. Moreover, the self-sustained high-density PDA@Ni100Co0 nanotube arrays obtained by removing the membrane structure possess a large aspect ratio, making them an efficient catalyst for pollutant capture. This cost-effective nanocatalyst approach has the great potential for large-scale applications in environmental remediation, highlighting its significant innovation and contribution to the field.