Highly efficient near-infrared photothermal antibacterial membrane with incorporated biogenic CuSe nanoparticles

Photothermal antibacterial membranes are attractive separation materials, but the high cost and poor solar utilization are currently two major hurdles to their widespread application. Here, we report the use of biogenic copper selenide nanoparticles (bio-CuSe) to fabricate low-cost photothermal antibacterial membranes. By using Shewanella oneidensis MR-1 cells as the biofactory, uniform-sized, near-infrared (NIR)-responsive bio-CuSe, with superior light-to-heat conversion efficiency (30.8%) over most reported copper chalcogenide nanomaterials, were facilely synthesized. The bio-CuSe together with bacterial cells were incorporated into a poly-vinylidene fluoride (PVDF) membrane to significantly improve the membrane hydrophilicity, surface smoothness and matrix cavities, which benefited a slightly improved water flux. The resulting bio-CuSe/ PVDF membrane showed 75% less biofilm development and improved antifouling properties towards bovine serum albumin (BSA) than the unmodified membrane in the dark. After NIR irradiation for 30 min, the water temperature at the membrane vicinity increased by 14.6 degrees C, allowing for > 95% suppression in bacterial growth. In addition, complete bacteriostasis was achieved by the dry membrane. Given the green-synthesis nature and superior NIR photothermal activity of the bio-CuSe-modified membrane, it holds a great potential for applications in multiple fields such as water and air purification, disinfection, therapy and various antibacterial products manufacturing.

Automated summary

Low-cost photothermal antibacterial membranes were fabricated using biogenic copper selenide nanoparticles, improving membrane antibacterial properties and water flux.