Artificial polydopamine interface for high-performance ambient particulate matter removal at large velocity

Ambient particulate matter (PM) has been identified as the fourth-ranking risk factor for mortality globally, and efficient ventilation filtration technologies are urgently needed. In most previous trials, however, high filtration efficiency was achieved either at a low face air velocity or at a large pressure drop cost. Here, nine coarse filters with in situ polydopamine (PDA) coatings were reported, which significantly improved the efficiency-pressure drop-energy consumption performance. By optimizing the filter substrate and synergistically modulating the electric fields, the artificial PDA coarse filter showed a high filtration efficiency of 96.9% for 0.3–0.5 μm particles, and a low pressure drop of 9.2 Pa at 1 m/s air velocity. At an extremely large air velocity of 4 m/s, the filtration efficiency remained as high as 94.3% for 1–3 μm particles. This work offers the engineering application opportunity for high-air-velocity filtration, paving the way to a safe, healthy, and energy-saving environment.