Your next water bottle might not even need filling – pulling water from the air instead
Scientists have created a sponge-like material that harvests litres of drinking water straight from the air
Quick Summary
Researchers have developed a sponge-like material that harvests drinking water directly from the atmosphere, even in relatively dry conditions.
The sunlight-powered composite could eventually be used in self-filling bottles and off-grid water collection systems.
Researchers have developed a new material that captures moisture from the air before turning it into clean drinking water, potentially paving the way for self-filling bottles and off-grid hydration systems.
Created by scientists at Australia’s RMIT University alongside collaborators in China, the sponge-like composite absorbs water vapour even when humidity levels are as low as 30% – conditions that would leave many existing atmospheric water harvesters struggling. Better still, it releases that water using only gentle warming from sunlight, avoiding the need for electricity or complex equipment.
The material combines naturally porous balsa wood with lithium chloride, a highly effective moisture-absorbing salt, all wrapped inside a layer of iron oxide nanoparticles.
Those particles efficiently convert sunlight into heat, speeding up the release of collected water while helping the system complete multiple collection cycles throughout the day.
In laboratory tests, the material absorbed around 2ml of water per gram overnight before releasing almost all of it during daylight. Outdoor trials showed it could harvest around 2.5ml per gram overnight and between 5ml and 13ml per gram over a full 24-hour period, depending on humidity levels.
The researchers believe scaling the technology up could eventually allow devices to generate several litres of drinking water each day.
It's easy to imagine the possibilities. A camping water bottle that slowly refills itself overnight. Emergency water supplies after natural disasters. Off-grid homes in remote regions. Even military or expedition equipment that reduces the amount of water people need to carry.
There's still a long road before you'll see this built into your favourite reusable bottle, but the science is promising. Like the stillsuits from Dune, the goal is simple: recover every drop of precious water possible. Thankfully, this version doesn't require wearing a full-body desert survival suit.
