An Electrically Renewable Air Filter with Integrated 3D Nanowire Networks

Abstract Particulate matter (PM) is a major pollutant in air and filtration at the source and on‐site is an effective approach to remedy PM pollution. Filters integrated with nanowires are advantageous for their high PM removal efficiency and low resistance to airflow. In this work, carbon nanowires are directly grown as 3D networks on a 304 stainless steel mesh to form a robust air filter. The growth of the carbon nanowires is initiated by exposing the stainless steel substrate to the vapor generated from the thermal decomposition of a silicone. The stainless steel is attacked by the carbon supersaturated vapor and releases metal nanoparticles, which catalyze the growth of carbon nanowires. The air filter with integrated 3D nanowire networks achieves a high PM removal efficiency with a low pressure drop. Moreover, the filter is heat resistant and can be renewed by electrical resistive heating to burn off the captured PM. After electrical renewal treatment, the filter recovers the low pressure drop while still maintaining a high PM removal efficiency. This air filter is promising for applications requiring on‐site renewal and will be useful for treating high temperature emissions.