News from the NNI Community - Research Advances Funded by Agencies Participating in the NNI

Scientists at Penn State have developed a new design for thermogels – materials that can be injected as a liquid and turn into a solid inside our bodies – that further improves these materials’ properties. The newly designed thermogels are made with nanoparticles that have sticky spots, similar to arms reaching out and giving the nanoparticles places to connect with one another and form a structure. The method may be especially appealing for soft tissue reconstruction, in which case thermogels could serve as structures that provide a framework for cells to stick to and form new, healthy tissue. 

Modern electron microscopes can capture incredibly detailed images of materials down to the atomic level, but they require a skilled operator and can only focus on very small areas at a time. Now, researchers from the U.S. Department of Energy’s (DOE) Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California, Berkeley, have created a n automated workflow that overcomes these limitations by allowing large amounts of data to be collected over wide areas without human intervention and then quickly transferred to supercomputers for real-time processing. Much of the work was done at The Molecular Foundry and the National Energy Research Scientific Computing Center, two DOE Office of Science user facilities at Berkeley Lab.

Polymer-coated nanoparticles loaded with therapeutic drugs show significant promise for cancer treatment. Over the past decade, researchers at the Massachusetts Institute of Technology (MIT) have created a variety of these nanoparticles using a technique called layer-by-layer assembly. To help move these nanoparticles closer to human use, the researchers have now come up with a manufacturing technique that allows them to generate larger quantities of the nanoparticles in a fraction of the time. The researchers have filed for a patent on the technology and are now working with MIT’s Deshpande Center for Technological Innovation in hopes of potentially forming a company to commercialize the technology. 

When materials are created on a nanometer scale, even the thermal energy present at room temperature can cause structural ripples. How these ripples affect the mechanical properties of these thin materials can limit their use in electronics and other key systems. Now, using a semiconductor manufacturing process, researchers from Binghamton University, Harvard University, Princeton University, Penn State, and the U.S. Department of Energy’s Argonne National Laboratory have created alumina structures that are 28 nanometers thick on a silicon wafer with thermal-like static ripples, and then tested these ripples with lasers to measure their behavior. The results match with theories proposed about such structural ripples. 

Researchers from Northwestern University and the University of California, San Diego, have developed new technology that could lead to the creation of a rapid point-of-care test for HIV infection. The technology uses a nanomechanical platform and tiny cantilevers to detect multiple HIV antigens at high sensitivity in a matter of minutes. Built into a solar-powered device, this technology could be taken to hard-to-reach parts of the world, where early detection remains a challenge to deliver fast interventions to vulnerable populations without waiting for lab results.

Engineers at Harvard University have created a bilayer metasurface made of two stacked layers of titanium dioxide nanostructures. Almost a decade ago, the engineers had unveiled the world’s first visible-spectrum metasurfaces – ultra-thin, flat devices patterned with nanostructures that could precisely control the behavior of light and enable applications in imaging systems, augmented reality, and communications. But the single-layer nanostructure design has been in some ways limiting. For example, previous metasurfaces put specific requirements on the manipulation of light’s polarization in order to control the light’s behavior. Using the facilities of the Center for Nanoscale Systems at Harvard, the engineers came up with a fabrication process for freestanding, sturdy structures of two metasurfaces that hold strongly together but do not affect each other chemically.

An international team led by Rutgers University-New Brunswick researchers has merged two lab-synthesized two-dimensional materials into a synthetic quantum structure once thought impossible to exist and produced an exotic structure expected to provide insights that could lead to new materials at the core of quantum computing. One slice of the quantum structure is made of dysprosium titanate, an inorganic compound used in nuclear reactors, while the other is composed of pyrochlore iridate, a new magnetic semimetal. The specific electronic and magnetic properties of the material developed by the researchers can help in creating very unusual yet stable quantum states, which are essential for quantum computing. 

The shape of nanoparticles depends on the choice of solvent and temperature during their growth. But the tiny seed particles that form first and that guide the formation of final nanoparticle shapes are too small to measure accurately. With the help of a supercomputer, Penn State researchers have developed computer simulations to model seed particles with 100 to 200 atoms. They found that the shapes of the tiny particles depend on the solvent composition and temperature in unexpected ways. Surprisingly, in some cases the shape of the seed particle changes dramatically when only a single atom is added or removed. 

Rice University researchers have developed an innovative solution to a pressing environmental challenge: removing and destroying per- and polyfluoroalkyl substances (PFAS), commonly called “forever chemicals.” By combining granular activated carbon saturated with PFAS and mineralizing agents like sodium or calcium salts, the researchers applied a high voltage to generate temperatures exceeding 3,000 degrees Celsius in under one second. The intense heat breaks down the strong carbon-fluorine bonds in PFAS, converting them into inert, nontoxic fluoride salts. Simultaneously, the granular activated carbon is upcycled into graphene, a valuable material used in industries ranging from electronics to construction. 

Researchers from The University of Texas at Dallas; Texas State University in San Marcos, TX; and Lintec of America in Plano, TX, as well as international collaborators,  have invented a new, inexpensive method in which fibers are coiled to make springlike artificial muscles. What’s unique about this method is that it doesn’t make use of a mandrel – a spindle that serves to support or shape the artificial muscles. The mandrel-free fabrication process involves inserting twist into individual fibers, causing them to coil back on themselves, and then plying the twisted fibers to create springlike coils. The researchers used the mandrel-free method to make high-spring-index carbon nanotube yarns, which could be used to harvest mechanical energy or as self-powered strain sensors.