Seminar Jamie SILK 26.05.2026

Development of a Sustainable Passive Atmospheric Water Harvesting Device

PhD Student, Jamie SILK

LMGP, Université Grenoble Alpes, CNRS, Grenoble INP, Grenoble, France

Abstract

Water is essential for human life, yet roughly two billion people worldwide still lack access to safely managed drinking water. With increasing pressure from rapid population growth and climate change, there is a critical need for water generation technologies that are low-cost, scalable, and environmentally sustainable. Passive atmospheric water harvesting offers a promising solution by capturing moisture from the air without continuous energy input, but current approaches are often limited by low efficiency or high cost. This study aims to optimize a bioinspired mixed-wettability surface to enhance passive water collection by promoting both droplet nucleation and rapid transport of condensed water. The surface is fabricated using superhydrophobic zinc oxide nanowire (NW) arrays synthesized via a scalable sol-gel/chemical bath deposition method, followed by functionalization with a non-fluorinated silane agent. Hydrophilic silica nanoparticles are then deposited on the superhydrophobic NW arrays to create the mixed wettability effect. Material performance is optimized by varying NW morphology, surface wettability, and nanoparticle concentration to maximize water collection rates. To induce condensation without energy input, this mixed-wettability surface is coupled with a passive daytime radiative cooling (PDRC) coating composed of bicontinuous interfacially jammed emulsion gels (bijels). These porous polymer films exhibit high solar reflectance and strong infrared emissivity, enabling sub-ambient cooling. The PDRC layer is optimized by adjusting domain size and film thickness to achieve maximum cooling performance. In parallel, a life cycle assessment (LCA) is conducted to evaluate the environmental impacts of material fabrication and identify key contributors to categories such as global warming potential, water use, and ozone depletion. This integrated approach informs design choices that minimize environmental burden. The results of this study show promise in developing a material with the ability to passively collect atmospheric water even in climates with low levels of humidity, potentially aiding in providing clean water globally in the face of the climate crisis.

Short Bio/CV

I am a PhD student at the LMGP lab studying passive atmospheric water harvesting technologies. I hold a Bachelor’s degree in Chemical Engineering and a Master’s degree in Sustainable Engineering for International Development from Villanova University (Pennsylvania, USA). During my master’s, my research studied the impact of climate change on drinking water resources in Madagascar, combining data from the latest IPCC climate models with local stakeholder knowledge and priorities to plan for future climate-related water challenges. In 2025, I spent four months as an invited researcher at the SMART LAB at the University of Pennsylvania, where I researched passive daytime radiative cooling coatings. My current research builds on this background, focusing on the development of environmentally sustainable, low-cost, scalable materials for passive water collection.