For decades, scientists have been studying a group of unusual materials called multiferroics that could be useful for a range of applications including computer memory, chemical sensors and quantum computers.
Recent research has demonstrated the effectiveness of ultrathin Bi4O5Br2 nanosheets with controlled oxygen vacancies in enhancing the piezocatalytic production of hydrogen peroxide (H2O2), presenting a viable, environmentally friendly alternative to traditional methods.
Hydrogen peroxide (H2O2) serves as a crucial chemical raw material with extensive applications in numerous industrial and everyday contexts. However, the industrial anthraquinone method of producing H2O2 is fraught with significant drawbacks, including high levels of pollution and energy consumption. An alternative approach involves harnessing ubiquitous mechanical energy for piezocatalytic H2O2 evolution, which offers a promising strategy. Despite its potential, this method faces challenges due to its unsatisfactory energy conversion efficiency.
Bi4O5Br2 is regarded as a highly attractive photocatalytic material due to its unique sandwich structure, excellent chemical stability, good visible light capture ability, and suitable band structure. Aspired by its non-centrosymmetric crystal structure, piezoelectric performance has begun to enter the vision of researchers recently. However, its potential as an efficient piezocatalyst is far from being exploited, especially since the impacts of defects on piezocatalysis and piezocatalytic H2O2 production over Bi4O5Br2 remains scanty. Thus, mechanical energy-driven piezocatalysis provides a promising method for H2O2 synthesis from pure water with great attraction.
Researchers have created a new class of materials called “glassy gels” that are very hard and difficult to break despite containing more than 50% liquid. Coupled with the fact that glassy gels are simple to produce, the material holds promise for a variety of applications.
Gels and glassy polymers are classes of materials that have historically been viewed as distinct from one another. Glassy polymers are hard, stiff and often brittle. They’re used to make things like water bottles or airplane windows. Gels – such as contact lenses – contain liquid and are soft and stretchy.
“We’ve created a class of materials that we’ve termed glassy gels, which are as hard as glassy polymers, but – if you apply enough force – can stretch up to five times their original length, rather than breaking,” says Michael Dickey, corresponding author of a paper on the work and the Camille and Henry Dreyfus Professor of Chemical and Biomolecular Engineering at North Carolina State University. “What’s more, once the material has been stretched, you can get it to return to its original shape by applying heat. In addition, the surface of the glassy gels is highly adhesive, which is unusual for hard materials.”
The element actinium was first discovered at the turn of the 20th century, but even now, nearly 125 years later, researchers still don’t have a good grasp on the metal’s chemistry. That’s because actinium is only available in extremely small amounts and working with the radioactive material requires special facilities. But to improve emerging cancer treatments using actinium, researchers will need to better understand how the element binds with other molecules.
Small-angle scattering (SAS) is a powerful technique for studying nanoscale samples. So far, however, its use in research has been held back by its inability to operate without some prior knowledge of a sample’s chemical composition. Through new research published in The European Physical Journal E, Eugen Anitas at the Bogoliubov Laboratory of Theoretical Physics in Dubna, Russia, presents a more advanced approach, which integrates SAS with machine learning algorithms.
Prussian blue (PB), a well-known pigment used to dye jeans, has been recognized as an emerging material for next-generation batteries. A team of researchers, led by Professor Hyun-Wook Lee in the School of Energy and Chemical Engineering at UNIST has made a significant breakthrough in the development of low-cost, high-performance lithium-ion batteries (LIBs) using PB, leading to significantly reduced battery prices.
Researchers from the Institute for Molecules and Materials at Radboud University, Netherlands, have demonstrated that a complex self-organizing chemical reaction network can perform various computational tasks, such as nonlinear classification and complex dynamics prediction.
Once upon a time, Earth was barren. Everything changed when, somehow, out of the chemistry available early in our planet’s history, something started squirming – processing available matter to survive, to breed, to thrive.
What that something was, and when it first squirmed, have been burning questions that have puzzled humanity probably for as long as we’ve been able to ask “what am I?”
Now, a new study has found some answers – and life emerged surprisingly early.
Life’s evolutionary timescale is typically calibrated to the oldest fossil occurrences. However, the veracity of fossil discoveries from the early Archaean period has been contested11,12. Relaxed Bayesian node-calibrated molecular clock approaches provide a means of integrating the sparse fossil and geochemical record of early life with the information provided by molecular data; however, constraining LUCA’s age is challenging due to limited prokaryote fossil calibrations and the uncertainty in their placement on the phylogeny. Molecular clock estimates of LUCA13,14,15 have relied on conserved universal single-copy marker genes within phylogenies for which LUCA represented the root. Dating the root of a tree is difficult because errors propagate from the tips to the root of the dated phylogeny and information is not available to estimate the rate of evolution for the branch incident on the root node. Therefore, we analysed genes that duplicated before LUCA with two (or more) copies in LUCA’s genome16. The root in these gene trees represents this duplication preceding LUCA, whereas LUCA is represented by two descendant nodes. Use of these universal paralogues also has the advantage that the same calibrations can be applied at least twice. After duplication, the same species divergences are represented on both sides of the gene tree17,18 and thus can be assumed to have the same age. This considerably reduces the uncertainty when genetic distance (branch length) is resolved into absolute time and rate. When a shared node is assigned a fossil calibration, such cross-bracing also serves to double the number of calibrations on the phylogeny, improving divergence time estimates. We calibrated our molecular clock analyses using 13 calibrations (see ‘Fossil calibrations’ in Supplementary Information). The calibration on the root of the tree of life is of particular importance. Some previous studies have placed a younger maximum constraint on the age of LUCA based on the assumption that life could not have survived Late Heavy Bombardment (LHB) (~3.7–3.9 billion years ago (Ga))19. However, the LHB hypothesis is extrapolated and scaled from the Moon’s impact record, the interpretation of which has been questioned in terms of the intensity, duration and even the veracity of an LHB episode20,21,22,23. Thus, the LHB hypothesis should not be considered a credible maximum constraint on the age of LUCA. We used soft-uniform bounds, with the maximum-age bound based on the time of the Moon-forming impact (4,510 million years ago (Ma) ± 10 Myr), which would have effectively sterilized Earth’s precursors, Tellus and Theia13. Our minimum bound on the age of LUCA is based on low δ98 Mo isotope values indicative of Mn oxidation compatible with oxygenic photosynthesis and, therefore, total-group Oxyphotobacteria in the Mozaan Group, Pongola Supergroup, South Africa24,25, dated minimally to 2,954 Ma ± 9 Myr (ref. 26).
Our estimates for the age of LUCA are inferred with a concatenated and a partitioned dataset, both consisting of five pre-LUCA paralogues: catalytic and non-catalytic subunits from ATP synthases, elongation factor Tu and G, signal recognition protein and signal recognition particle receptor, tyrosyl-tRNA and tryptophanyl-tRNA synthetases, and leucyl-and valyl-tRNA synthetases27. Marginal densities (commonly referred to as effective priors) fall within calibration densities (that is, user-specified priors) when topologically adjacent calibrations do not overlap temporally, but may differ when they overlap, to ensure the relative age relationships between ancestor-descendant nodes. We consider the marginal densities a reasonable interpretation of the calibration evidence given the phylogeny; we are not attempting to test the hypothesis that the fossil record is an accurate temporal archive of evolutionary history because it is not28.
Ishida, T. Sci Rep 14, 2086 (2024). https://doi.org/10.1038/s41598-024-52475-9
