With the final GPS III satellite scheduled to launch in March, the United States is completing the most significant upgrade to its positioning, navigation, and timing (PNT) infrastructure in more than a decade. GPS III delivers improved accuracy, stronger signals and enhanced anti-jam capabilities for military users. By any technical measure, it is a better […]
Synthetic materials such as plastics are designed to be durable and water resistant. But the processing required to achieve these properties results in a lack of biodegradability, leading to an accumulation of plastic pollution that affects both the environment and human health. Researchers at the Institute for Bioengineering of Catalonia (IBEC) are developing a possible replacement for plastics: a novel biomaterial based on chitin, the second most abundant natural polymer on Earth.
“Every year, nature produces on the order of 1011 tonnes of chitin, roughly equivalent to more than three centuries of today’s global plastic production,” says study leader Javier G Fernández. “Chitin and [its derivative] chitosan are the ultimate natural engineering polymers. In nature, variations of this material produce stiff insect wings enabling flight, elastic joints enabling extraordinary jumping in grasshoppers, and armour-like protective exoskeletons in lobsters or clams.”
But while biomaterials provide a more environmentally friendly alternative to conventional plastics, most biological materials weaken when exposed to water. In this latest work, Fernández and first author Akshayakumar Kompa took inspiration from nature and developed a new biomaterial that increases its strength when in contact with water, while maintaining its natural biodegradability.
Metal matters
In the exoskeletons of insects and crustaceans, chitin it is secreted in a gel-like form into water and then transitions into a hard structure. Following a chance observation that removing zinc from a sandworm’s fangs caused them to soften in water, Kompa and Fernández investigated whether adding a different transition metal, nickel, to chitosan could have the opposite effect.
By mixing nickel chloride solution (at concentrations from 0.6 to 1.4 M) with dispersions of chitosan extracted from discarded shrimp shells, the researchers entrapped varying amounts of nickel within the chitosan structure. Fourier-transform infrared spectra of resulting chitosan films revealed the presence of nickel ions, which form weak hydrogen bonds with water molecules and increase the biomaterial’s capacity to bond with water.
“In our films, water molecules form reversible bridges between polymer chains through weak interactions that can rapidly break and reform under load,” Fernández explains. “That fast reconfiguration is what gives the material high strength and toughness under wet conditions: essentially a built-in, stress-activated ‘self-rearrangement’ mechanism. Nickel ions act as stabilizing anchors for these water-mediated bridges, enabling more and longer-range connections and making inter-chain connectivity more robust”.
The nickel-doped chitosan samples had tensile strengths of between 30 and 40 MPa, similar to that of standard plastics. Adding low concentrations of nickel did not significantly impact the mechanical properties of the films. Concentrations of 1 M or more, however, preserved the material’s strength while increasing its toughness (the ability to stretch before breaking) – a key goal in the field of structural materials and a feature unique to biological composites.
Increased strength Testing a nickel-doped chitosan film using a 20 kg dumbbell. (Courtesy: Institute for Bioengineering of Catalonia)
Upon immersion in water, the nickel-doped films exhibited greater tensile strength, increasing from 36.12±2.21 MPa when dry to 53.01±1.68 MPa, moving into the range of higher-performance engineering plastics. In particular, samples created from an optimal 0.8 M nickel concentration almost doubled in strength when wet (and were used for the remainder of the team’s experiments).
Scaling production
The manufacturing process involves an initial immersion in water, followed by drying for 24 h and then re-wetting. During the first immersion, any nickel ions that are not incorporated into the material’s functional bridging network are released into the water, ensuring that nickel is present only where it is structurally useful.
The researchers developed a zero-waste production cycle in which this water is used as a primary component for fabricating the next object. “The expelled nickel is recovered and used to make the next batch of material, so the process operates at essentially 100% nickel utilization across batches,” says Fernández.
Zero waste production The team created structures including a 3 m2 nickel-doped chitosan film and a cup that can retain water as effectively as common plastics. (Courtesy: Institute for Bioengineering of Catalonia)
They used this process to produce various nickel-doped chitosan objects, including watertight containers and a 1 m2 film that could support a 20 kg weight after 24 h of water immersion. They also created a 244 x 122 cm film with similar mechanical behaviour to the smaller samples, demonstrating the potential for rapid scaling to ecologically relevant scales. A standard half-life test revealed that after approximately four months buried in garden soil, half of the material had biodegraded.
The researchers suggest that the biomaterial’s first real-world use may be in sectors such as agriculture and fishing that require strong, water-compatible and ultimately biodegradable materials, likely for packaging, coatings and other water-exposed applications. Both nickel and chitosan are already employed within biomedicine, making medicine another possible target, although any new medical product will require additional regulatory and performance validation.
The team is currently setting up a 1000 m2 lab facility in Barcelona, scheduled to open in 2028, for academia–industry collaborations in sustainable bioengineering research. Fernández suggests that we are moving towards a “biomaterial age”, defined by the ability to “control, integrate, and broadly use biomaterials and biological principles within engineering applications”.
“Over the last 20 years, working on bioinspired manufacturing, we have been able to produce the largest bioprinted objects in the world, demonstrated pathways for resource-secure and sustainable production in urban environments, and even explored how these approaches can support interplanetary colonization,” he tells Physics World. “Now we are achieving material properties that were considered out of reach by designing the material to work with its environment, rather than isolating itself from it.”
A new SpaceX initiative to provide space traffic coordination services has attracted attention and praise in part because of the conditions it places on users of it.
A long-awaited cap on liability for U.K. launch operators came into force Feb. 18, aiming to make the country’s fledgling rocket sector more competitive as it struggles to get off the ground.
Electronics made from certain atomically thin materials can survive harsh radiation environments up to 100 times longer than traditional silicon-based devices. This finding, which comes from researchers at Fudan University in Shanghai, China, could bring significant benefits for satellites and other spacecraft, which are prone to damage from intense cosmic radiation.
Cosmic radiation consists of a mixture of heavy ions and cosmic rays, which are high-energy protons, electrons and atomic nuclei. The Earth’s magnetic field protects us from 99.9% of this ionizing radiation, and our atmosphere significantly attenuates the rest. Space-based electronics, however, have no such protection, and this radiation can damage or even destroy them.
Adding radiation shielding to spacecraft mitigates these harmful effects, but the extra weight and power consumption increases the spacecraft’s costs. “This conflicts with the requirements of future spacecraft, which call for lightweight and cost-effective architectures,” says team leader Peng Zhou, a physicist in Fudan’s College of Integrated Circuits and Micro-Nano Electronics. “Implementing radiation tolerant electronic circuits is therefore an important challenge and if we can find materials that are intrinsically robust to this radiation, we could incorporate these directly into the design of onboard electronic circuits.”
Promising transition-metal dichalcogenides
Previous research had suggested that 2D materials might fit the bill, with transistors based on transition-metal dichalcogenides appearing particularly promising. Within this family of materials, 2D molybdenum disulphide (MoS2) proved especially robust to irradiation-induced defects, and Zhou points out that its electrical, mechanical and thermal properties are also highly attractive for space applications.
The studies that revealed these advantages were, however, largely limited to simulations and ground-based experiments. This meant they were unable to fully replicate the complex and dynamic radiation fields such circuits would encounter under real space conditions.
Better than NMOS transistors
In their work, Zhou and colleagues set out to fill this gap. After growing monolayer 2D MoS2 using chemical vapour deposition, they used this material to fabricate field-effect transistors. They then exposed these transistors to 10 Mrad of gamma-ray irradiation and looked for changes to their structure using several techniques, including cross-sectional transmission electron microscopy (TEM) imaging and corresponding energy-dispersive spectroscopy (EDS) mapping.
These measurements indicated that the 2D MoS2 in the transistors was about 0.7 nm thick (typical for a monolayer structure) and showed no obvious signs of defects or damage. Subsequent Raman characterization on five sites within the MoS2 film confirmed the devices’ structural integrity.
The researchers then turned their attention to the transistors’ electrical properties. They found that even after irradiation, the transistors’ on-off ratios remained ultra-high, at about 108. They note that this is considerably better than a similarly-sized Si N-channel metal–oxide–semiconductor (NMOS) transistors fabricated through a CMOS process, for which the on-off ratio decreased by a factor of more than 4000 after the same 10 Mrad irradiation.
The team also found that MoS2 system consumes only about 49.9 mW per channel, making its power requirement at least five times lower than the NMOS one. This is important owing to the strict energy limitations and stringent power budgets of spacecraft, Zhou says.
Surviving the space environment
In their final experiment, the researchers tested their MoS2 structures on a spacecraft orbiting at an altitude of 517 km, similar to the low-Earth orbit of many communication satellites. These tests showed that the bit-error rate in data transmitted from the structures remained below 10-8 even after nine months of operation, which Zhou says indicates significant radiation and long-term stability. Indeed, based on test data, electronic devices made from these 2D materials could operate for 271 years in geosynchronous orbit – 100 times longer than conventional silicon electronics.
“The discovery of intrinsic radiation tolerance in atomically thin 2D materials, and the successful on-orbit validation of the atomic-layer semiconductor-based spaceborne radio-frequency communication system have opened a uniquely promising pathway for space electronics leveraging 2D materials,” Zhou says. “And their exceptionally long operational lifetimes and ultra-low power consumption establishes the unique competitiveness of 2D electronic systems in frontier space missions, such as deep-space exploration, high-Earth-orbit satellites and even interplanetary communications.”
The researchers are now working to optimize these structures by employing advanced fabrication processes and circuit designs. Their goal is to improve certain key performance parameters of spaceborne radio-frequency chips employed in inter-satellite and satellite-to-ground communications. “We also plan to develop an atomic-layer semiconductor-based radiation-tolerant computing platform, providing core technological support for future orbital data centres, highly autonomous satellites and deep-space probes,” Zhou tells Physics World.
In this work, the researchers theoretically explore how quantum materials can transition continuously from one ordered state to another, for example, from a magnetic phase to a phase with crystalline or orientational order. Traditionally, such order‑to‑order transitions were thought to require fractionalisation, where particles effectively split into exotic components. Here, the team identifies a new route that avoids this complexity entirely.
Their mechanism relies on two renormalisation‑group fixed points in the system colliding and annihilating, which reshapes the flow of the system and removes the usual disordered phase. A separate critical fixed point, unaffected by this collision, then becomes the new quantum critical point linking the two ordered phases. This allows for a continuous, seamless transition without invoking fractionalised quasiparticles.
The authors show that this behaviour could occur in several real or realistic systems, including rare‑earth pyrochlore iridates, kagome quantum magnets, quantum impurity models and even certain versions of quantum chromodynamics. A striking prediction of the mechanism is a strong asymmetry in energy scales on the two sides of the transition, such as a much lower critical temperature and a smaller order parameter where the order emerges from fixed‑point annihilation.
This work reveals a previously unrecognised kind of quantum phase transition, expands the landscape beyond the usual Landau-Ginzburg-Wilson framework, which is the standard theory for phase transitions, and offers new ways to understand and test the behaviour of complex quantum systems.
Unlike crystals, whose atoms arrange themselves in tidy, repeating patterns, glass is a non‑equilibrium material. A glass is formed when a liquid is cooled so quickly that its atoms never settle into a regular pattern, instead forming a disordered, unstructured arrangement.
In this process, as temperature decreases, atoms move more and more slowly. Near a certain temperature –theglass transition temperature – the atoms move so slowly that the material effectively stops behaving like a liquid and becomes a glass.
This isn’t a sharp, well‑defined transition like water turning to ice. Instead, it’s a gradual slowdown: the structure appears solid long before the atoms would theoretically cease to rearrange.
This slowdown can be extrapolated and be used to predict the temperature at which the material’s internal rearrangement would take infinitely long. This hypothetical point is known as the ideal glass transition. It cannot be reached in practice, but it provides an important reference for understanding how glasses behave.
Despite years of research, it’s still not clear exactly how glass properties depend on how it was made – how fast it was cooled, how long it aged, or how it was mechanically disturbed. Each preparation route seems to give slightly different behaviour.
For decades, scientists have struggled to find a single measure that captures all these effects. How do you describe, in one number, how disordered a glass is?
Recent research has emerged that provides a compelling answer: a configurational distance metric. This is a way of measuring how far the internal structure of a piece of glass is from a well‑defined reference state.
When the researchers used this metric, they could neatly collapse data from many different experiments onto a single curve. In other words, they found a single physical parameter controlling the behaviour.
This worked across a wide range of conditions: glasses cooled at different rates, allowed to age for different times, or tested under different strengths and durations of mechanical probing.
As long as the experiments were conducted above the ideal glass transition temperature, the metric provided a unified description of how the material dissipates energy.
This insight is significant. It suggests that even though glass never fully reaches equilibrium, its behaviour is still governed by how close it is to this idealised transition point. In other words, the concept of the kinetic ideal glass transition isn’t just theoretical, it leaves a measurable imprint on real materials.
This research offers a powerful new way to understand and predict the mechanical behaviour of glasses in everyday technologies, from smartphone screens to industrial coatings.
The discovery of an antibiotic-resistant microbe locked in Romanian cave ice highlights both the risks of a warming world and an unexpected source of future medicines.
SAN FRANCISCO – After attracting cubesat customers, Belgium-based Simera Sense is developing higher-resolution optical payloads for larger satellites. To date, Simera Sense customers have sent more than 50 xScape100 and xScape200 cameras into orbit. Most have flown on cubesats ranging in size from 6u to 16u. For larger satellites, Simera Sense is developing standardized optical payloads […]
Chinese launch startup Space Epoch has secured B-round funding as the company moves towards a first orbital launch and recovery attempt late this year.
Electrochemical CO2 reduction converts CO2 to higher-value products using an electrocatalyst and could pave the way for electrification of the chemical industry. A key challenge for CO2 reduction is its poor selectivity (faradaic efficiency) due to competition with the hydrogen evolution reaction in aqueous electrolytes. Rotating ring-disk electrode (RRDE) experiments have become a popular method to quantify faradaic efficiencies, especially for gold electrocatalysts. However, such measurements suffer from poor inter-laboratory reproducibility. This work identifies the causes of variability in RRDE selectivity measurements by comparing protocols with different electrochemical methods, reagent purities, and glassware cleaning procedures. Electroplating of electrolyte impurities onto the disk and ring surfaces were identified as major contributors to electrocatalyst deactivation. These results highlight the need for standardized and cross-laboratory validation of CO2RR selectivity measurements using RRDE. Researchers implementing this technique for CO2RR selectivity measurements need to be cognizant of electrode deactivation and its potential impacts on faradaic efficiencies and overall conclusions of their work.
Maria Kelly
Maria Kelly is a Jill Hruby Postdoctoral Fellow at Sandia National Laboratories. She earned her PhD in Professor Wilson Smith’s research group at the University of Colorado Boulder and the National Renewable Energy Laboratory. Her doctoral work focused on characterization of carbon dioxide conversion interfaces using analytical electrochemical and in situ scanning probe methods. Her research interests broadly encompass advancing experimental measurement techniques to investigate the near-electrode environment during electrochemical reactions.
Earth observation startup SatVu said Feb. 17 it has raised $41 million in a funding round that included the NATO Innovation Fund, as commercial space-based thermal imagery gains traction with defense and intelligence agencies.
Space-Comm Expo is one of Europe’s premier space industry events and the largest event in the UK, taking place in just 2 weeks’ time 4-5 March, ExCeL London. Over 5,400 […]
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