In early 2023, scientists at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory used autonomous methods can discover new materials. The artificial intelligence (AI)-driven technique led to the discovery of three new nanostructures, including a first-of-its-kind nanoscale ladder.
Scanning-electron microscopy images depict novel nanostructures discovered by artificial intelligence. Researchers describe the patterns as skew (left), alternating lines (center), and ladder (right). Scale bars are 200 nanometers.
Their discovery of the nanoscale ladder and other new structures further widens the scope of self-assembly’s applications.
“Self-assembly can be used as a technique for nanopatterning, which is a driver for advances in microelectronics and computer hardware,” said CFN scientist and co-author Gregory Doerk. “These technologies are always pushing for higher resolution using smaller nanopatterns. You can get really small and tightly controlled features from self-assembling materials, but they do not necessarily obey the kind of rules that we lay out for circuits, for example. By directing self-assembly using a template, we can form patterns that are more useful.”
“The fact that we can now create a ladder structure, which no one has ever dreamed of before, is amazing,” said CFN group leader and co-author Kevin Yager. “Traditional self-assembly can only form relatively simple structures like cylinders, sheets, and spheres. But by blending two materials together and using just the right chemical grating, we’ve found that entirely new structures are possible.”
Blending self-assembling materials together has enabled CFN scientists to uncover unique structures, but it has also created new challenges. With many more parameters to control in the self-assembly process, finding the right combination of parameters to create new and useful structures is a battle against time. To accelerate their research, CFN scientists leveraged a new AI capability: autonomous experimentation.
Plasmonics are special optical phenomena that are understood as interactions between light and matter and possess diverse shapes, material compositions, and symmetry-related behavior. The design of such plasmonic structures at the nanoscale level can pave the way for optical materials that respond to the orientation of light (polarization), which is not easily achievable in bulk size and existing materials.
In a significant leap forward for quantum nanophotonics, a team of European and Israeli physicists has introduced a new type of polaritonic cavities and redefined the limits of light confinement. This pioneering work, detailed in a study published in Nature Materials, demonstrates an unconventional method to confine photons, overcoming the traditional limitations in nanophotonics.
A coating that can hide objects in plain sight, or an implant that behaves exactly like bone tissue—these extraordinary objects are already made from "metamaterials." Researchers from TU Delft have now developed an AI tool that not only can discover such extraordinary materials but also makes them fabrication-ready and durable. This makes it possible to create devices with unprecedented functionalities. They have published their findings in Advanced Materials.
Engineering researchers have developed a 2D printing process using liquid metals that they say could create new ways of creating more advanced and energy efficient computing hardware that is manufactured at the nanoscale.
The process comes amid increasing worldwide demand for memory devices, which require significant amounts of energy to produce and use.
"Reducing the temperature at which zirconium and hafnium become liquid is crucial to developing lower-cost electrical devices as far less energy is required," said Dr. Mohammad Ghasemian, the study's lead author from the School of Chemical and Biomolecular Engineering.
Liquid Lightning: Nanotechnology Unlocks New Energy
MARCH 13, 2024
EPFL researchers have discovered that nanoscale devices harnessing the hydroelectric effect can harvest electricity from the evaporation of fluids with higher ion concentrations than purified water, revealing a vast untapped energy potential.
Evaporation is a natural process so ubiquitous that most of us take it for granted. In fact, roughly half of the solar energy that reaches the earth drives evaporative processes. Since 2017, researchers have been working to harness the energy potential of evaporation via the hydrovol~aic (HV) effect, which allows electricity to be harvested when fluid is passed over the charged surface of a nanoscale device. Evaporation establishes a continuous flow within nanochannels inside these devices, which act as passive pumping mechanisms. This effect is also seen in the microcapillaries of plants, where water transport occurs thanks to a combination of capillary pressure and natural evaporation.
Although hydrovoltaic devices currently exist, there is very little functional understanding of the conditions and physical phenomena that govern HV energy production at the nanoscale. It’s an information gap that Giulia Tagliabue, head of the Laboratory of Nanoscience for Energy Technology (LNET) in the School of Engineering, and PhD student Tarique Anwar wanted to fill. They leveraged a combination of experiments and multiphysics modelling to characterize fluid flows, ion flows, and electrostatic effects due to solid-liquid interactions, with the goal of optimizing HV devices.
“Thanks to our novel, highly controlled platform, this is the first study that quantifies these hydrovoltaic phenomena by highlighting the significance of various interfacial interactions. But in the process, we also made a major finding: that hydrovoltaic devices can operate over a wide range of salinities, contradicting prior understanding that highly purified water was required for best performance,” says Tagliabue.
A printable organic polymer that assembles into chiral structures when printed has enabled researchers to reliably measure the amount of charge produced in spin-to-charge conversion within a spintronic material at room temperature. The polymer's tunable qualities and versatility make it desirable not only for less expensive, environmentally friendly, printable electronic applications, but also for use in understanding chirality and spin interactions more generally.
Spintronic devices are electronic devices that harness the spin of an electron, rather than its charge, to create energy-efficient current used for data storage, communication, and computing. Chiral materials refer to materials that cannot be imposed on their mirror image—think of your left and right hands, for example. If you lay your left hand over your right, the finger positions are reversed. That is chirality.
Chirality in spintronic materials allows designers to control the direction of spin within the material, known as the "chirality-induced spin selectivity (CISS)" effect. The CISS effect occurs when charge current flows along the chiral axis in a chiral material, producing spin—or charge-to-spin conversion—without needing ferromagnetic elements. Charge-to-spin conversion is necessary for memory storage in computing devices.
Making ever smaller and more powerful chips requires new ultrathin materials: 2D materials that are only 1 atom thick, or even just a couple of atoms. Think about graphene or ultra-thin silicon membrane for instance.
Scientists at TU Delft have taken an important step in application of these materials: they can now measure important thermal properties of ultrathin silicon membranes. A major advantage of their method is that no physical contact needs to be made with the membrane, so pristine properties can be measured and no complex fabrication is required.
The findings are published in the journal APL Materials.
Medical implants could fail less often when coated with a microscopically crinkled, ceramic material designed by researchers at the University of Michigan. The coating is described in a paper published in ACS Applied Materials and Interfaces.
The material's very tiny crinkles are the perfect size for young bone cells and immune cells to latch onto. With their firmer grip on the coatings, human cells can strongly adhere to the implant and stretch out along its surface. Stretched bone cells develop faster, and stretched immune cells tend to help heal tissue and reduce inflammation rather than attack the implant as a foreign invader, so the researchers think their coatings could make medical implants more successful.
Researchers at Rensselaer Polytechnic Institute have fabricated a device no wider than a human hair that will help physicists investigate the fundamental nature of matter and light. Their findings, published in the journal Nature Nanotechnology, could also support the development of more efficient lasers, which are used in fields ranging from medicine to manufacturing.
Improving fingerprint detection with carbon-coated nanoparticles
by Samuel Jarman, SciencePOD
Fingerprint detection is one of the most important techniques in forensic investigation. When fingerprints are dusted with a carbon-based powder, the material will adhere to the moisture and grease left behind by the unique patterns of ridges and valleys on the perpetrator's fingertip. The resulting pattern can then be analyzed under a microscope, and compared with suspects' fingerprints.
Researchers create orientation-independent magnetic field-sensing nanotube spin qubits
October 2, 2024
Tongcang Li, a professor of physics and electrical and computer engineering, leads a team that has developed the BNNTs with optically active spin qubits. He also is on the faculty of the Purdue Quantum Science and Engineering Institute. The team includes Xingyu Gao, Sumukh Vaidya and Saakshi Dikshit, graduate students at Purdue who are co-authors of a paper published in the peer-reviewed journal Nature Communications.
"BNNT spin qubits are more sensitive to detecting off-axis magnetic fields than a diamond nitrogen-vacancy center, which is primarily sensitive to fields that are parallel to its axis, but not perpendicular," Li said. "BNNTs also are more cost-effective and offer more resilience than brittle diamond tips."
BNNT applications include quantum-sensing technology that measures changes in magnetic fields and collects and analyzes data at the atomic level.
"They also have applications in the semiconductor industry and nanoscale MRI, or magnetic resonance imaging," Gao said.
Li disclosed the nanotube spin qubits to the Purdue Innovates Office of Technology Commercialization, which has applied for patents to protect the intellectual property.
Nature and plastics inspire breakthrough in soft sustainable materials
October 9, 2024
Using peptides and a snippet of the large molecules in plastics, Northwestern University materials scientists have developed materials made of tiny, flexible nano-sized ribbons that can be charged just like a battery to store energy or record digital information. Highly energy efficient, biocompatible and made from sustainable materials, the systems could give rise to new types of ultralight electronic devices while reducing the environmental impact of electronic manufacturing and disposal.
The study will publish on Wednesday (Oct. 9) in the journal Nature.
With further development, the new soft materials could be used in low-power, energy-efficient microscopic memory chips, sensors and energy storage units. Researchers also could integrate them into woven fibers to create smart fabrics or sticker-like medical implants. In today's wearable devices, electronics are clunkily strapped to the body with a wristband. But, with the new materials, the wristband itself could have electronic activity.
"This is a wholly new concept in materials science and soft materials research," said Northwestern's Samuel I. Stupp, who led the study. "We imagine a future where you could wear a shirt with air conditioning built into it or rely on soft bioactive implants that feel like tissues and are activated wirelessly to improve heart or brain function.
"Those uses require electrical and biological signals, but we cannot build those applications with classic electroactive materials. It's not practical to put hard materials into our organs or in shirts that people can wear. We need to bring electrical signals into the world of soft materials. That is exactly what we have done in this study."
“In the quantum multiverse, every choice, every decision you've ever and never made exists in an unimaginably vast ensemble of parallel universes.”
Shaping nanocrystals: Unlocking the future of screens, solar and medical tech
12 hours ago
From brighter TV screens to better medical diagnostics and more efficient solar panels, new Curtin-led research has discovered how to make more molecules stick to the surface of tiny nanocrystals, in a breakthrough that could lead to improvements in everyday technology.
Lead author Associate Professor Guohua Jia from Curtin's School of Molecular and Life Sciences, said the study investigated how the shape of zinc sulfide nanocrystals affected how well molecules, known as ligands, stick to their surface. The full study titled "Deciphering surface ligand density of colloidal semiconductor nanocrystals: Shape matters" is published in the Journal of the American Chemical Society.
"Ligands play an important role in controlling the behavior and performance of zinc sulfide nanocrystals in various important technologies," Associate Professor Jia said.
"In a discovery that could open new possibilities for developing smarter, more advanced devices, our study found flatter, more even particles called nanoplatelets allow more ligands to attach tightly, compared to other shapes like nanodots and nanorods.
"By adjusting the shape of these particles, we were able to control how they interacted with their surroundings and make them more efficient in various applications. From brighter LED lights and screens to more efficient solar panels and more detailed medical imaging, the ability to control particle shapes could revolutionize product efficiency and performance."
The next step for fully integrated textile-based electronics to make their way from the lab to the wardrobe is figuring out how to power the garment gizmos without unfashionably toting around a solid battery. Researchers from Drexel University, the University of Pennsylvania, and Accenture Labs in California have taken a new approach to the challenge by building a full textile energy grid that can be wirelessly charged. In their recent study, the team reported that it can power textile devices, including a warming element and environmental sensors that transmit data in real-time.
Published in the journal Materials Today, the paper describes the process and viability of building the grid by printing on nonwoven cotton textiles with an ink composed of MXene, a type of nanomaterial created at Drexel, that is at that same time highly conductive and durable enough to withstand the folding, stretching and washing that clothing endures.
Nanotechnology: Flexible biosensors with modular design
November 8, 2024
LMU researchers have developed a strategy that enables biosensors to be easily adapted for a wide range of applications.
Biosensors play a key role in medical research and diagnostics. At present, however, they generally have to be specially developed for each application. A team led by LMU chemist Philip Tinnefeld has developed a general, modular strategy for designing sensors that can be easily adapted to various target molecules and concentration ranges. As the researchers report in the journal Nature Nanotechnology, their new modular sensor has the potential to significantly accelerate the development of new diagnostic tools for research.
The sensor uses a DNA origami scaffold, which consists of two arms connected by a molecular "hinge." Each arm is tagged with a fluorescent dye, and the distance between the tags is recorded by means of fluorescence resonance energy transfer (FRET). In a closed state, the two arms are parallel; when the structure opens, the arms fold out to form an angle of up to 90°. "As a result of this large conformational change, the fluorescence signal also changes substantially," explains Viktorija Glembockyte, senior author of the study. "This allows signals to be measured with considerably greater clarity and precision than in systems with small conformational changes."
Graphene, a single layer of carbon atoms arranged in a two-dimensional honeycomb lattice, is known for its exceptional properties: incredible strength (about 200 times stronger than steel), light weight, flexibility, and excellent conduction of electricity and heat. These properties have made graphene increasingly important in applications across various fields, including electronics, energy storage, medical technology, and, most recently, quantum computing.
Graphene's quantum properties, such as superconductivity and other unique quantum behaviors, are known to arise when graphene atomic layers are stacked and twisted with precision to produce "ABC stacking domains." Historically, achieving ABC stacking domains required exfoliating graphene and manually twisting and aligning layers with exact orientations—a highly intricate process that is difficult to scale for industrial applications.
A breakthrough in decoding the growth process of hexagonal boron nitride (hBN), a 2D material, and its nanostructures on metal substrates could pave the way for more efficient electronics, cleaner energy solutions and greener chemical manufacturing, according to new research from the University of Surrey published in the journal Small.
Only one atom thick, hBN—often nicknamed "white graphene"—is an ultra-thin, super-resilient material that blocks electrical currents, withstands extreme temperatures and resists chemical damage. Its unique versatility makes it an invaluable component in advanced electronics, where it can protect delicate microchips and enable the development of faster, more efficient transistors.
