Discover Top Posts Tagged with #nanoribbons

Scientists advance multi-purpose photocatalyst for clean hydrogen production and agricultural pollutant degradation

Can we use nothing more than sunlight and inexpensive materials to produce clean hydrogen fuel while also removing toxic pollutants from water? That question shaped our recent work with γ-In2S3, a semiconductor that has intrigued researchers for years but still holds untapped potential. By making subtle changes at the atomic scale, we discovered that we could significantly enhance its performance under visible light without adding noble metals or forming complex heterojunctions. We began with a simple idea: modify γ-In2S3 in a controlled and practical way. Using a straightforward heating method, we synthesized ultrathin γ-In2S3 nanoribbons. We then introduced small amounts of Mg2+, Ca2+, and Sr2+ ions into the structure. Although γ-In2S3 has been widely studied for energy and environmental applications, no one had explored doping it with this group of alkaline-earth metals. We sought to determine how these subtle substitutions would affect its structure and catalytic behavior.

Phosphorene nanoribbons shown to exhibit magnetic and semiconductor properties at room temperature

Scientists have long suspected that phosphorene nanoribbons (PNRs)—thin pieces of black phosphorus, only a few nanometers wide—might exhibit unique magnetic and semiconducting properties, but proving this has been difficult. In a recent study published in Nature, researchers focused on exploring the potential for magnetic and semiconducting characteristics of these nanoribbons. Using techniques such as ultrafast magneto-optical spectroscopy and electron paramagnetic resonance they were able to demonstrate the magnetic behavior of PNRs at room temperature, and show how these magnetic properties can interact with light. The study, carried out at the Cavendish Laboratory in collaboration with other institutes, including the University of Warwick, University College London, Freie Universität Berlin and the European High Magnetic Field lab in Nijmegen, revealed several key findings about phosphorene nanoribbons.

Newly discovered sheets of nanoscale 'cubes' found to be efficient catalysts

Researchers from Tokyo Metropolitan University have created sheets of transition metal chalcogenide "cubes" connected by chlorine atoms. While sheets of atoms have been widely studied, e.g. graphene, the team's work breaks new ground by using clusters instead. The research is published in the journal Advanced Materials. The team succeeded in forming nanoribbons inside carbon nanotubes for structural characterization, while also forming microscale sheets of cubes which could be exfoliated and probed. These were shown to be an excellent catalyst for generating hydrogen. Two-dimensional materials are a breakthrough in nanotechnology, realizing materials with exotic electronic and physical properties which are specific to their sheet-like nature.

New method may facilitate the use of graphene nanoribbons in nanoelectronics

An international collaborative study that features researchers from Tel Aviv University (TAU), presented a new method for growing ultra-long and ultra-narrow strips of graphene (a derivative of graphite), which exhibit semiconducting properties that can be harnessed by the nanoelectronics industry. The researchers believe that the development may have many potential technological applications, including advanced switching devices, spintronic devices, and in the future, even quantum computing architectures. The study was conducted under the leadership of an international research team that included Prof. Michael Urbakh and Prof. Oded Hod from TAU's School of Chemistry, as well as scientists from China, South Korea, and Japan. The study was published in the journal Nature. Prof. Urbakh and Prof. Hod explain that graphene is actually a single layer of graphite made of carbon atoms and built similar to the shape of a beehive. Graphene is very suitable for technological uses.

One-atom-thick phosphorus/arsenic alloy ribbons could improve batteries, solar cells and sensors

Researchers at UCL have created one-atom-thick ribbons made of phosphorus alloyed with arsenic that could dramatically improve the efficiency of devices such as batteries, supercapacitors and solar cells. The research team discovered phosphorus nanoribbons in 2019. The "wonder material," predicted to revolutionize devices ranging from batteries to biomedical sensors, has since been used to increase lithium-ion battery lifetimes and solar cell efficiencies. However, phosphorus-only materials do not conduct electricity very well, hindering their usage for certain applications. In the new study, published in the Journal of the American Chemical Society, the researchers created nanoribbons made of phosphorus and tiny amounts of arsenic, which they found were able to conduct electricity at temperatures above -140°C, while retaining the highly useful properties of the phosphorus-only ribbons.

Study explores mechanical properties of molybdenum disulfide nanoribbons with armchair edges

The properties of nanoribbon edges are important for their applications in electronic devices, sensors, and catalysts. A group of scientists from Japan and China studied the mechanical response of single-layer molybdenum disulfide nanoribbons with armchair edges using in situ transmission electron microscopy. They showed that the nanoribbon Young's modulus varied inversely with its width below the width of 3nm, indicating a higher bond stiffness for the armchair edges. Their work, published in the journal Advanced Science, was co-authored by Associate Professor Kenta Hongo and Professor Ryo Maezono from JAIST and Lecturer Chunmeng Liu and Lecturer Jiaqi Zhang from Zhengzhou University, China. Sensors have become ubiquitous in the modern world, with applications ranging from detecting explosives, measuring physiological spikes of glucose or cortisol non-invasively to estimating greenhouse gas levels in the atmosphere.

Scientists weave atomically thin wires into ribbons

Researchers from Tokyo Metropolitan University have succeeded in using nanowires of a transition-metal chalcogenide to make atomically thin nanoribbons. Bundles of nanowires were exposed to a gas of chalcogen atoms and heat which helped merge the threads into narrow strips. Nanoribbons are highly sought after for sophisticated electronic devices; given the scalability of the method, the team hopes it will see widespread use in the industrial production of cutting-edge materials.

As circuitry gets smaller, faster and more energy-efficient, scientists are faced with the increasingly difficult challenge of controlling the atomic-level structure of the materials that are used in them. One promising avenue of research is the use of intricate threads of material only a few atoms wide; one such structure is composed of transition-metal chalcogenides, a combination of transition metals and chalcogens, atoms which share a column with oxygen on the periodic table. These atomically thin nanowires possess properties unique to their one-dimensional structure and are highly sought after for sophisticated electronic devices. But what they have in minuteness, they lack in tunability. This is where nanoribbons, narrow, atomically thin sheets, come in. Fine control of their width, for example, leads to controlled variation in their electronic and magnetic properties.

Phosphorene nanoribbons live up to hype in first demonstration

Researchers have incorporated phosphorene nanoribbons into new types of solar cells, dramatically improving their efficiency.

Phosphorene nanoribbons (PNRs) are ribbon-like strands of the 2D material phosphorous, which, similar to graphene, are made of single-atom-thick layers of atoms. PNRs were first produced in 2019, and hundreds of theoretical studies have predicted how their properties could enhance all kinds of devices, including batteries, biomedical sensors, and quantum computers.

However, none of these predicted exciting properties have so far been demonstrated in actual devices. Now, for the first time, a team led by Imperial College London and University College London researchers has used PNRs to significantly improve the efficiency of a device—a new kind of solar cell—demonstrating that the 'wonder material' may indeed live up to its hype.

The details are published today in the Journal of the American Chemical Society.

#nanoribbons

Trending Tags

Recently Viewed Tags

#nanoribbons