Hydrogen, out of thin air!

What if every breath you take contains the solution to a low-carbon future? New research suggests that moisture in the air could be harvested and converted into hydrogen fuel using nothing more than sunlight.

Hydrogen is often touted as a cornerstone in plans to phase out fossil fuels. It has potential as a low-carbon raw material for the chemical industry and as a fuel for transport, powering planes, trucks, and cars such as Toyota’s Mirai. Yet despite its green reputation, hydrogen has seen limited real-world adoption.

The problem lies in how we produce it. The cleanest existing method splits water into hydrogen and oxygen using electricity. But this comes with caveats: the water must be clean, posing challenges in regions facing freshwater scarcity, and the process is energy-intensive. In addition, if the electricity used comes from fossil fuels, the climate benefits quickly disappear.

“Researchers have developed a system that extracts water directly from the air and splits it into hydrogen without requiring an external water supply or electricity”

To sidestep these limitations, researchers have developed a system that extracts water directly from the air and splits it into hydrogen without requiring an external water supply or electricity. Instead, it exploits natural day-night cycles. At night, the system adsorbs water vapour from the air; during the day, sunlight drives a reaction that releases hydrogen gas from the water.

The technology has two key components. The first is a metal-organic framework (MOF), an extremely porous material that acts like a sponge, soaking up water vapour. MOFs gained wider attention after being recognised with 2025’s Nobel Prize in Chemistry. The second component is a platinum catalyst, which drives the chemical reaction that splits water. These materials are engineered into nanoparticles and combined into a thin membrane.

What makes the design novel is how these components work together. Beyond splitting water, the platinum catalyst also helps cool the system, enhancing the MOF’s ability to adsorb moisture. Crucially, the process uses water vapour rather than liquid water, avoiding problems seen in earlier designs where liquid water blocked the absorption of sunlight or trapped the hydrogen produced.

While still far from large-scale deployment, the research points to a compelling idea: that future sustainable technologies might rely less on complex infrastructure, and more on the air around us and the sun above us.

Babies, Bach and finding the beat

A group based at the Italian Institute of Technology have found that babies seem to be born with an innate ability to recognise musical rhythms, but an understanding of melody comes later. The findings offer new insight into how auditory processing develops in early life.

The researchers used electroencephalography (EEG) to measure the electrical activity of the brains of sleeping babies while playing them musical recordings of Bach piano pieces. They looked at responses to the unaltered pieces as well as ‘shuffled’ versions, where the timing and pitch of the notes were randomised so the music did not have a predictable rhythm or melody.

“Exposure to rhythmic stimuli while in the womb enables fetuses to develop sensitivity to rhythm before birth”

A computational model was used to analyse the EEG data. In particular, the group were interested in how the babies responded to unexpected events in the unaltered music – i.e., moments that did not fit with the rhythm or melody.

They found that the babies tended to register disruptions to the timing of notes as being surprising, suggesting their brains were tracking rhythmic patterns and predicting what should come next. However, unexpected changes in pitch did not elicit the same surprise, implying that the infants were not forming similar predictions about melody.

The researchers suggested that exposure to rhythmic stimuli while in the womb – for example, the sound of their mother’s heartbeat, or the rhythmic motion produced by her walking – enables fetuses to develop sensitivity to rhythm before birth. In contrast, the distortion of sound by amniotic fluid means fetuses are only exposed to a narrow range of pitches, and the ability to recognise melody likely develops after birth through exposure to speech and music.

Similar patterns to those in the babies have been observed in other species, including rhesus monkeys. The first author of the study suggested that an understanding of rhythm might therefore reflect “ancient auditory abilities that we share with other primates,” while melody is “shaped by learning after birth”. This distinction may help explain why patterns of rhythm are often similar in music from different cultures, while melody tends to be far more diverse.