Material Science News and Discussions

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New class of 2D material displays stable charge density wave at room temperature
https://phys.org/news/2024-03-class-2d- ... table.html
by Patricia DeLacey, University of Michigan College of Engineering

Quantum materials have generated considerable interest for computing applications in the past several decades, but non-trivial quantum properties—like superconductivity or magnetic spin—remain in fragile states.

"When designing quantum materials, the game is always a fight against disorder," said Robert Hovden, an associate professor of materials science and engineering at the University of Michigan.

Heat is the most common form of disorder that disrupts quantum properties. Quantum materials often only exhibit exotic phenomena at very low temperatures when the atom nearly stops vibrating, allowing the surrounding electrons to interact with one another and rearrange themselves in unexpected ways. This is why quantum computers are currently being developed in baths of liquid helium at −269 °C, or around -450 F. That's just a few degrees above zero Kelvin (-273.15 °C).

Materials can also lose quantum properties when exfoliated from 3D down to a 2D single layer of atoms, thinness of particular interest for developing nanoscale devices.

Now, a University of Michigan-led research team has developed a new way to induce and stabilize an exotic quantum phenomenon called a charge density wave at room temperature. They've essentially identified a new class of 2D materials. The results are published in Nature Communications.

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Scientists develop new system to record 2D crystal synthesis in real time
https://phys.org/news/2024-03-scientist ... -real.html
by Silvia Cernea Clark, Rice University

Materials scientists at Rice University are shedding light on the intricate growth processes of 2D crystals, paving the way for controlled synthesis of these materials with unprecedented precision.

Two-dimensional materials such as graphene and molybdenum disulfide (MoS2) exhibit unique properties that hold immense promise for applications in electronics, sensors, energy storage, biomedicine and more. However, their complex growth mechanisms—inconsistent correlations exist between how the conditions for growth affect the shapes of crystals—have posed a significant challenge for researchers.

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Novel design enhances thermal insulation and impact resistance in composite glass
https://techxplore.com/news/2024-03-the ... osite.html
by University of Science and Technology of China

A research team led by Prof. Ni Yong and Prof. He Linghui from the University of Science and Technology of China (USTC) of the Chinese Academy of Sciences (CAS) has developed a new composite glass combining the nacre-inspired structure and shear stiffening gel (SSG) material, maintaining transparency while exhibiting excellent thermal insulation and impact resistance. Their work was published in Advanced Materials.

Bulk glass serves as an indispensable structural material in people's daily lives. However, glass has poor thermal insulation and is prone to fracture under impact, making it the weakest component in most buildings and transportation vehicles. There is an urgent need to develop new composite transparent materials with comprehensive performance.

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Phase-change concrete melts snow and ice without salt or shovels
By Paul McClure
March 18, 2024

Incorporating a phase-change material into concrete, researchers have created a self-heating material that can melt snow and ice for up to 10 hours without using salt or shovels. The novel material could reduce the need for plowing and salting and help preserve the integrity of road surfaces.

According to the US Department of Transportation (DOT), more than 70% of roads are in snowy regions. Snow and ice accumulation reduces road friction and vehicle maneuverability, causing drivers to slow and increasing the risk of crashes. Snow-obstructed lanes and roads also reduce roadway capacity and increase travel time.

https://newatlas.com/materials/phase-ch ... ting-snow/

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Researchers develop bendable energy storage materials
https://techxplore.com/news/2024-03-ben ... rials.html
by Pohang University of Science and Technology

Imagine being able to wear your smartphone on your wrist, not as a watch, but literally as a flexible band that surrounds around your arm. How about clothes that charge your gadgets just by wearing them?

Recently, a collaborative team led by Professor Jin Kon Kim and others has brought a step closer to making this realty. This research work was published in Advanced Materials.

Mesoporous metal oxides (MMOs) are characterized by pores ranging from 2 to 50 nanometers (nm) in size. Due to their extensive surface area, MMOs have various applications, such as high-performance energy storage and efficient catalysis, semiconductors, and sensors. However, the integration of MMOs on wearable and flexible devices remains a great challenge, because plastic substrates could not maintain their integrity at elevated temperatures (350°C or above) where MMOs could be synthesized.

Researchers use nitrogen-based compounds as new high-performance energy storage materials
https://phys.org/news/2024-03-nitrogen- ... nergy.html
by Jennifer Opel, Bayreuth University

Researchers at the University of Bayreuth have synthesized unique scandium polynitrides under extreme conditions, with exotic chemistry and potential applications as high-energy-density materials.

High-energy density materials (HEDMs) are pivotal in various applications due to their superior energetic performance, which includes high detonation velocity, detonation pressure, and energy storage capacity. Their application in space exploration as rocket propellants and in defense as explosives is of critical importance for modern society.

The unique chemical properties of these materials, such as the ability to store vast amounts of energy in a relatively small volume, make them indispensable for advancing technology in areas requiring high-power outputs and compact energy storage solutions.

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New reactor could save millions when making ingredients for plastics and rubber from natural gas
https://techxplore.com/news/2024-03-rea ... ubber.html
by Derek Smith, University of Michigan

A new way to make an important ingredient for plastics, adhesives, carpet fibers, household cleaners and more from natural gas could reduce manufacturing costs in a post-petroleum economy by millions of dollars, thanks to a new chemical reactor designed by University of Michigan engineers.

The reactor creates propylene, a workhorse chemical that is also used to make a long list of industrial chemicals, including ingredients for nitrile rubber found in automotive hoses and seals as well as blue protective gloves. Most propylene used today comes from oil refineries, which collect it as a byproduct of refining crude oil into gasoline.

As oil and gasoline fall out of vogue in favor of natural gas, solar, and wind energy, production of propylene and other oil-derived products could fall below the current demand without new ways to make them.

Natural gas extracted from shale holds one potential alternative to propylene sourced from crude oil. It's rich in propane, which resembles propylene closely enough to be a promising precursor material, but current methods to make propylene from natural gas are still too inefficient to bridge the gap in supply and demand.

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"First plastic demonstrated to not create microplastics" has been tested
By Paul McClure
March 22, 2024

https://newatlas.com/environment/algae- ... egradable/
Even when it’s ground into microparticles, 97% of an algae-based plastic biodegrades in compost and water in under seven months, a new study has reported. The researchers hope their plastic will eventually replace existing petroleum-based ones, which have caused concern due to their effects on health and the environment.

In recent years, there has been a great deal of chatter about – and research into – microplastics, the tiny, almost indestructible fragments shed from everyday plastic products. Much of that research has focused on devising ways of collecting and removing microplastics from the environment to prevent the health problems they can cause.

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Scientists develop ultra-thin semiconductor fibers that turn fabrics into wearable electronics
https://phys.org/news/2024-03-scientist ... ibers.html
by Nanyang Technological University

Scientists from NTU Singapore have developed ultra-thin semiconductor fibers that can be woven into fabrics, turning them into smart wearable electronics. Their work has been published in the journal Nature.

To create reliably functioning semiconductor fibers, they must be flexible and without defects for stable signal transmission. However, existing manufacturing methods cause stress and instability, leading to cracks and deformities in the semiconductor cores, negatively impacting their performance and limiting their development.

NTU scientists conducted modeling and simulations to understand how stress and instability occur during the manufacturing process. They found that the challenge could be overcome through careful material selection and a specific series of steps taken during fiber production.

They developed a mechanical design and successfully fabricated hair-thin, defect-free fibers spanning 100 meters, which indicates its market scalability. Importantly the new fibers can be woven into fabrics using existing methods.

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Thin, Bacteria-coated Fibers Could Lead to Self-healing Concrete That Fills in its Own Cracks
by Mohammad Houshmand and Yaghoob Farnam
March 22, 2024

Introduction:

(The Conversation) Some say there are two types of concrete – cracked and on the brink of cracking. But what if when concrete cracked, it could heal itself?

We’re part of a team of materials scientists and microbiologists that has harnessed the power of bacteria to create biological fibers that initial results suggest can heal cracks in concrete. We’re working on a technology that, if we work out the kinks and manage to bring it to the market one day, could extend the life span of concrete.

Cracking concrete

Picture a bridge exposed to snow, rain, temperature changes and trucks carrying heavy loads. The concrete on the bridge will gradually develop cracks from stress and wear. Over time, these cracks expand, allowing water and corrosive substances that weaken the concrete to penetrate further down.

At some point, local authorities have to pay for repairs, which are not only expensive but also disrupt traffic and drain public resources.

Now, consider a medical patient recovering from a severe injury. As the patient’s cells recognize the damage, they release tiny healing agents – like microscopic repair crews. These agents target the wounded area, mending tissues and restoring the cells’ functionality. What if concrete had the same kind of self-healing ability as human tissue?

Read more here: https://theconversation.com/thin-bacte ... s-220190

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New topological metamaterial amplifies sound waves exponentially
https://phys.org/news/2024-03-topologic ... ially.html
by AMOLF

Researchers at AMOLF, in collaboration with partners from Germany, Switzerland, and Austria, have realized a new type of metamaterial through which sound waves flow in an unprecedented fashion. It provides a novel form of amplification of mechanical vibrations, which has the potential to improve sensor technology and information processing devices.

This metamaterial is the first instance of a so-called "bosonic Kitaev chain," which gets its special properties from its nature as a topological material. It was realized by making nanomechanical resonators interact with laser light through radiation pressure forces.

The discovery, which is published in the journal Nature, was achieved in an international collaboration between AMOLF, the Max Planck Institute for the Science of Light, the University of Basel, ETH Zurich, and the University of Vienna.