A metre-scale vertical origami hydrogel panel for atmospheric water harvesting in Death Valley

Abstract

Water scarcity impacts over 2.2 billion people globally, especially in underdeveloped, landlocked or off-grid regions. Passive sorbent-based atmospheric water harvesting offers a promising solution by converting ubiquitous atmospheric moisture into liquid water. However, current approaches are limited by low water production (a few millilitres a day), the release of unsafe lithium ions and poor efficiency in conditions of low relative humidity. Here we report an atmospheric water harvesting window (AWHW) featuring a vertical origami hydrogel panel and a window-like solar still. This passive, metre-scale device was tested in Death Valley, producing 57.0–161.5 ml of water a day across a relative humidity range of 21–88%. The device has a lifespan of at least 1 year and delivers safe water with lithium ion concentrations below 0.06 ppm. Our AWHW sets a benchmark in daily water production and climate adaptability, representing an advance towards practical, scalable, safe and sustainable decentralized water solutions for the most water-stressed regions. Water scarcity is a global issue that demands urgent resolution, but current approaches are inadequate. Now a metre-scale atmospheric water harvester, featuring a hygroscopic origami hydrogel panel and a window-like glass chamber, demonstrates exceptional efficiency in extracting water from air, even in extremely arid conditions.