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Graphene membranes offer efficient, low-cost option for industrial CO₂ capture

Carbon capture is becoming essential for industries that still depend on fossil fuels, including the cement and steel industries. Natural-gas power plants, coal plants, and cement factories all release large amounts of CO₂, and reducing those emissions is difficult without dedicated capture systems. Today, most plants rely on solvent-based systems that absorb CO₂, but these setups use a lot of heat, require major infrastructure, and can be costly to run.

A smaller, electricity-driven alternative is what the field calls a “membrane” system. A membrane works like an ultra-fine filter that lets certain gases slip through more easily than others, separating CO₂ from the rest of the flue gas. The problem is that many membranes lose efficiency when CO₂ levels are low, which is common in natural-gas plants, and this limits where they can be used.

A new study at EPFL has now analyzed how a new membrane material, pyridinic-graphene, could work at scale. This is a single-layer graphene sheet with tiny pores that favor CO₂ over other gases. The researchers combined experimental performance data with modeling tools that simulate real operating conditions, such as energy use and gas flow. They also explored a wide range of cost scenarios to see how the material might behave once deployed in commercial plants.

Enlarging the Periodic Table of Laser-Cooled Molecules

A class of molecules with two valence electrons has been laser cooled and trapped for the first time.

Over the past 70 years, physicists have developed laser-based methods for controlling atoms and molecules, but much of this success has been concentrated on a few columns of the periodic table. For molecules, laser cooling has been limited to diatomic species that have a single unpaired valence electron for interacting with light. Extending laser cooling to molecules with two valence electrons has long been sought after (Fig. 1). The most promising nonreactive candidates are diatomic molecules that partner a halogen, such as fluorine (F) or chlorine (Cl), with a p-block atom, such as aluminum (Al) or thallium (Tl). Several research groups have specifically targeted AlF, AlCl, and TlF, but these molecules are difficult to work with because of their deep-ultraviolet transitions, complicated energy-level structures, and small magnetic moments.

Earth’s atmosphere may help support human life on the moon

The moon’s surface may be more than just a dusty, barren landscape. Over billions of years, tiny particles from Earth’s atmosphere have landed in the lunar soil, creating a possible source of life-sustaining substances for future astronauts. But scientists have only recently begun to understand how these particles make the long journey from Earth to the moon and how long the process has been taking place.

New research from the University of Rochester, published in Communications Earth & Environment, shows that Earth’s magnetic field may actually help guide atmospheric particles—carried by solar wind—into space, instead of blocking them. Because Earth’s magnetic field has existed for billions of years, this process could have steadily moved particles from Earth to the moon over very long periods of time.

“By combining data from particles preserved in lunar soil with computational modeling of how solar wind interacts with Earth’s atmosphere, we can trace the history of Earth’s atmosphere and its magnetic field,” says Eric Blackman, a professor in the Department of Physics and Astronomy and a distinguished scientist at URochester’s Laboratory for Laser Energetics (LLE).

Dual substitution induces room-temperature ferromagnetism and negative thermal expansion in BiFeO₃

Using a dual-cation substitution approach, researchers at Science Tokyo introduced ferromagnetism into bismuth ferrite, a well-known and promising multiferroic material for next-generation memory technologies. By replacing ions at both the bismuth and iron sites with calcium ions and heavier elements, they modified the spin structure and achieved ferromagnetism at room temperature. Additionally, negative thermal expansion was observed. This ability to engineer magnetism and thermal expansion in a multiferroic material aids in realizing future memory devices.

Multiferroic materials, which show both ferroelectricity and ferromagnetism, hold strong potential for use in low-power memory devices where information can be written electrically and read magnetically. Among these materials, bismuth ferrite (BiFeO3) is one of the most widely studied because it combines ferroelectricity with antiferromagnetism at room temperature.

However, BiFeO3 naturally forms a cycloidal spin structure, which is a wave-like pattern of rotating spins. This pattern cancels out any net magnetization and makes the material difficult to use in magnetic devices.

New window insulation blocks heat, but not your view

Physicists at the University of Colorado Boulder have designed a new material for insulating windows that could improve the energy efficiency of buildings worldwide—and it works a bit like a high-tech version of Bubble Wrap.

The team’s material, called Mesoporous Optically Clear Heat Insulator (MOCHI), comes in large slabs or thin sheets that can be applied to the inside of any window. So far, the team only makes the material in the lab, and it’s not available for consumers. But the researchers say MOCHI is long-lasting and is almost completely transparent.

That means it won’t disrupt your view, unlike many insulating materials on the market today.

All-optical modulation in silicon achieved via an electron avalanche process

Over the past decades, engineers have introduced numerous technologies that rely on light and its underlying characteristics. These include photonic and quantum systems that could advance imaging, communication and information processing.

A key challenge that has so far limited the performance of these new technologies is that most materials used to fabricate them have a weak optical nonlinearity. This essentially means that they do not strongly change in response to light of different intensities.

A strong optical linearity is of crucial importance for the development of ultrafast optical switches, devices that can control either light or electrical signals by modulating the properties of a light-based signal (e.g. its intensity or path). Notably, these switches are central components of fiber optics-based communication systems, photonic devices and quantum technologies.

How Earth’s mantle locked away vast amounts of water in early magma ocean

Some 4.6 billion years ago, Earth was nothing like the gentle blue planet we know today. Frequent and violent celestial impacts churned its surface and interior into a seething ocean of magma—an environment so extreme that liquid water could not exist, leaving the entire planet resembling an inferno.

Since 70% of Earth’s surface is now covered in oceans, the mystery of how water survived and preserved on our planet from an early molten to a mostly solid state has long been a subject of scientific study.

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