Design theory-based nanostructured leaf-vein networks for selective VOC sensing

The importance of indoor air quality monitoring to safeguard the health of children and vulnerable adults in the UK cannot be overstated. A primary source of indoor air pollution is everyday household products and materials which emit harmful non-methane volatile organic compounds (VOCs), such as formaldehyde, toluene and phthalates. Even in minute concentrations, these specific compounds can induce a variety of respiratory, neurological, and endocrine disorders over prolonged low-level exposures. However, current environmental sensors, including those commercialised by major semiconductor integrated device manufacturers and by specialised gas sensor manufacturers, cannot specifically detect these different toxic gases at an acceptable concentration level. Therefore, they are unable to provide any helpful preventive guidance.

The project aims to create advanced material building blocks that respond selectively to specific gas molecules. Using solution-phase additive manufacturing techniques, these blocks will be assembled on a large scale into structures that mimic the intricate patterns found in plant xylems and leaf veins. These natural structures have evolved over millions of years to efficiently transport fluids with minimal energy, and the project’s design will replicate this efficiency.

By incorporating multiple levels of interconnected channels, the approach will optimize the flow of gases through the engineered blocks, leading to rapid, highly sensitive, and selective detection of toxic gases. This innovative design will enable the development of new training algorithms that significantly cut down the time and cost typically required for sensor calibration.