Efficient and Robust Metallic Nanowire Foams for Deep Submicrometer Particulate Filtration

TL;DR

This paper presents a new type of metallic nanowire foam filter that is highly efficient, durable, and reusable for filtering submicrometer airborne viruses and particulates, addressing urgent health safety needs.

Contribution

The development of nanowire-based low-density metal foams with high filtration efficiency and excellent mechanical and chemical properties for particulate filtration.

Findings

Filtration efficiency exceeds 96.6% for PM0.3 particles.

The metal foams are mechanically stable, lightweight, and resistant to chemicals and radiation.

They are easy to clean, reusable, and recyclable.

Abstract

The on-going COVID-19 pandemic highlights the severe health risks posed by deep submicron sized airborne viruses and particulates in the spread of infectious diseases. There is an urgent need for the development of efficient, durable and reusable filters for this size range. Here we report the realization of efficient particulate filters using nanowire-based low-density metal foams which combine extremely large surface areas with excellent mechanical properties. The metal foams exhibit outstanding filtration efficiencies (>96.6%) in the PM_{0.3} regime, with potentials for further improvement. Their mechanical stability and light weight, chemical and radiation resistance, ease of cleaning and reuse, and recyclability further make such metal foams promising filters for combating COVID-19 and other types of airborne particulates.