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Quasi-liquid layer controls growth mechanisms of ice-like materials

Clathrate hydrates are crystalline structures formed at the bottom of seafloors, created by water molecules trapping methane, carbon dioxide or other molecules. While these materials are underutilized in technology, a University of Oklahoma researcher is helping scientists better understand them through a trailblazing study.

Alberto Striolo, a professor in OU’s Gallogly College of Engineering, co-authored an article published in the Proceedings of the National Academy of Sciences that addresses a key challenge toward utilizing hydrates: their slow growth rates. He and his fellow researchers have discovered an unusual interfacial layer on the hydrate that impacts its growth rate.

Striolo is the college’s Asahi Glass Chair in Chemical Engineering and Lloyd and Jane Austin Presidential Professor. He is also the director of the college’s Online Master of Science in Sustainability and the Materials Science and Engineering doctoral program.

Integrated strategy unlocks 29.76% efficiency for all-perovskite tandem solar cells

Two stacked layers comprise tandem solar cells (TSCs), with each subcell absorbing different wavelengths of sunlight, which makes TSCs more efficient than single-layer solar cells. All-perovskite TSCs hold great promise for next-generation photovoltaics, with a theoretical efficiency exceeding 40%. However, their practical performance is hampered by mismatched crystallization kinetics between their wide-bandgap (WBG) and narrow-bandgap (NBG) subcells, leading to phase segregation and defect accumulation.

To address this challenge, a research group led by Prof. Ge Ziyi and Prof. Liu Chang from the Ningbo Institute of Materials Technology and Engineering of the Chinese Academy of Sciences has developed an innovative colloidal chemistry strategy to enhance the performance of these TSCs, achieving a power conversion efficiency (PCE) of 29.76%. Their study is published in Joule.

The researchers designed a unified carboxylate-based modulator system using two graded carboxylate anions—tartrate (Ta-) and citrate (Cit-)—to precisely regulate the nucleation dynamics of the two subcells.

Scientists Just Broke the Solar Power Limit Everyone Thought Was Absolute

A new “energy-multiplying” solar breakthrough could push efficiency beyond 100% and transform how we capture sunlight.

Solar energy is widely seen as a key tool in reducing reliance on fossil fuels and slowing climate change. The Sun delivers a vast amount of energy to Earth every second, but today’s solar cells can only capture a small portion of it. This limitation comes from a so-called “physical ceiling” that has long been considered unavoidable.

Breakthrough spin-flip technology boosts solar efficiency.

Shrinking the carbon footprint of chemical manufacturing with lasers and solar radiation

Researchers have found a way to use solar energy to power a key chemical reaction that drives many manufacturing industries. This new method can significantly reduce the energy required to run these operations, eliminate harsh oxidizing byproducts and minimize carbon emissions.

Olefin epoxidation is not a process many are familiar with, but the epoxide chemicals it produces are the backbone of the textile, plastic, chemical and pharmaceutical industries. However, the current industry-standard process uses harsh peroxides to facilitate oxidation reactions, which are difficult to dispose of safely and emit carbon dioxide.

Water can be used as an oxidant instead of peroxides, but H2O bonds are difficult to break, requiring high-temperature conditions, making it highly energy-intensive and further contributing to CO2 emissions.

Social media feeds: Algorithm redesign could break echo chambers and reduce online polarization

Scroll through social media long enough and a pattern emerges. Pause on a post questioning climate change or taking a hard line on a political issue, and the platform is quick to respond—serving up more of the same viewpoints, delivered with growing confidence and certainty.

That feedback loop is the architecture of an echo chamber: a space where familiar ideas are amplified, dissenting voices fade, and beliefs can harden rather than evolve.

But new research from the University of Rochester has found that echo chambers might not be a fact of online life. Published in IEEE Transactions on Affective Computing, the study argues that they are partly a design choice—one that could be softened with a surprisingly modest change: introducing more randomness into what people see.

Lab study suggests longer waves fracture floating ice sheets at lower stress

When waves are moving across ice-covered seas, they can cause sheets of ice to bend and ultimately break. Understanding the processes underlying these wave-induced ice fractures and predicting when they will occur could help to better forecast how climate change will impact the environment and marine ecosystems on Earth.

Researchers at PMMH Lab, ESPCI, CNRS, PSL University, Sorbonne Université and Université Paris Cité recently performed a new laboratory experiment aimed at shedding new light on this phenomenon. The results of this experiment, published in Physical Review Letters, suggest that the stress at which ice sheets break depends on the length of the underlying waves.

“Since 2021, we wanted to study the propagation of ocean waves in floating ice, with laboratory-scale experiments, and in particular the fracture of a thin sheet by a surface wave,” said Stéphane Perrard, senior author of the paper, told Phys.org. “We were later inspired by the work of E. Dumas Lefevbre and D. Dumont, who monitored the fracture of a real sea ice layer by the wake of an icebreaker. To study a small-scale analog of their experiment, we used the concept of scale invariance: the same physical phenomenon can occur at very different scales, as long as the key ingredients are conserved across scales.”

Proton-trapping MNene transforms ammonia production for food security and economic growth

With a new electrochemical synthesis via an electrochemical nitrogen reduction reaction (NRR), achieving carbon-free ammonia production is closer to reality through work from Drs. Abdoulaye Djire and Perla Balbuena, chemical engineering professors at Texas A&M University, and graduate students David Kumar and Hao En Lai. A topic outlined in their recent paper published in the Journal of the American Chemical Society introduces NRR, which produces ammonia in a cleaner and simpler way by using renewable electricity.

The research branches off of the team’s previous work, where they looked further into enabling two-dimensional materials in renewable energy.

“The current process of making ammonia is energy intensive and emits a lot of carbon dioxide, so if you can make ammonia electrochemically, then you can avoid these two negative effects,” Djire said. “During the electrochemical NRR process, water provides the hydrogen atoms, which combine with nitrogen from the air to form ammonia, all powered by electricity.”

Methane’s Elaborate Phases and Where to Find Them

A systematic exploration of the phase diagram of methane resolves inconsistencies of earlier studies, with potential ramifications for our understanding of planetary interiors.

As a gas, methane is very simple. But as a liquid and as a solid, it is perplexingly complex. Ambiguity has long plagued our observations and measurements of its structure at different pressure–temperature combinations. Yet, understanding methane’s phase diagram is vital for predicting its behavior deep within our and other planets. In a tour de force contribution Mengnan Wang at the University of Edinburgh in the UK and her colleagues have now charted the turbulent seas of the methane phase diagram [1]. By comprehensively mapping its phases and melting curve, they have resolved the legion of discrepancies of earlier studies.

Methane—one of the simplest of all molecules—is sometimes the subject of flatulence jokes (of which it is odorlessly innocent) but is also a powerful driver of climate change on Earth (of which it is very guilty [2]). The extraction of gaseous methane from Earth drives multibillion-dollar industries, which use the molecule both as a fuel and as a source of hydrogen. Out in the Solar System, methane in planetary atmospheres absorbs red light, which makes Uranus and Neptune shine blue, while icy methane damaged by radiation paints dwarf planets red.

Amorphous passivation strategy creates efficient, durable and flexible perovskite solar cells

Solar cells, devices that convert sunlight into electricity, are helping to reduce greenhouse gas emissions worldwide, promoting a shift toward renewable energy sources. Most solar cells used today are based on silicon, yet researchers have recently been exploring the potential of other photovoltaic materials, particularly perovskites.

Perovskites are a class of photovoltaic materials with strong light absorption. In practical devices, perovskite thin films are typically polycrystalline, meaning they consist of many small crystalline grains. As perovskites absorb sunlight so efficiently, a film thinner than ~1 μm can capture most of the incident solar radiation, whereas conventional crystalline silicon usually requires hundreds of micrometers of active material.

This combination of strong absorption and ultrathin active layers makes perovskite thin-film solar cells particularly well suited for lightweight, flexible, high-efficiency photovoltaic devices. Despite these many advantages, perovskites still face inherent challenges, such as achieving true mechanical flexibility, operational stability, and maintaining high efficiency at large areas simultaneously.

A Review of Polylactic Acid (PLA) and Poly(3-hydroxybutyrate) (PHB) as Bio-Sourced Polymers for Membrane Production Applications

In recent years, membranes have found extensive applications, primarily in wastewater purification and food packaging. However, petroleum-based membranes can be detrimental to the environment. For this reason, extensive studies are being conducted to identify environmentally friendly substitutes for the materials used in membrane composition. Among these materials, polylactic acid (PLA) and poly(3-hydroxybutyrate) (PHB) are two bio-sourced and biodegradable polymers that can be derived from lignocellulosic waste. These polymers also possess suitable characteristics, such as thermal resistance and mechanical strength, which make them potential candidates for replacing conventional plastics.

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