Environment

Researchers at Penn Engineering have made a surprising discovery: a new type of material that can pull water from the air and release it onto surfaces without any need for external energy. Originally stumbled upon by accident during unrelated experiments, the material combines water-attracting and water-repelling components at the nanoscale in a way that allows it to both capture moisture and push it out as visible droplets.

Scientists at Lawrence Berkeley National Laboratory (Berkeley Lab) and SLAC National Accelerator Laboratory have revealed the fundamental mechanisms that limit the performance of copper nanocatalysts – critical components in chemical reactions that transform carbon dioxide and water into valuable fuels and chemicals. Copper’s catalytic properties quickly degrade during these reactions, diminishing its performance over time.

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.

Researchers from The State University of New York, Buffalo; St. Bonaventure University; and Stony Brook University have created a molecular nanocage that captures the bulk of per- and polyfluoroalkyl substances (PFAS) found in water – and it works better than traditional filtering techniques that use activated carbon. Made of an organic nanoporous material designed to capture only PFAS, this tiny chemical-based filtration system removed 80% of PFAS from sewage and 90% of PFAS groundwater, while showing very low adverse environmental effects.

Researchers at The Ohio State University have developed a new material that, by harnessing the power of sunlight, can clear water of dangerous pollutants. Solar fuel systems that use titanium dioxide nanoparticles can cause significant challenges to implementation, including low efficiency and the need for complex filtration systems. So, the researchers added copper to the nanoparticles, and the new structures, called nanomats, can now absorb enough light energy to break down harmful pollutants in air and water.

Researchers at Northwestern University have created a new platform for monitoring chemical contaminants in the environment. The platform can detect the metals lead and cadmium at concentrations down to two and one parts per billion, respectively, in a matter of minutes. It was created by interfacing nanomechanical microcantilevers with synthetic biology biosensors. When the tiny cantilevers are coated with DNA molecules, biosensing molecules bind to the DNA, causing the cantilevers to bend.

Researchers from Rutgers University, the New Jersey Institute of Technology, the Connecticut Agricultural Experiment Station in New Haven, CT, and the Environmental and Occupational Health Sciences Institute in Piscataway, NJ, have shown that microplastic and nanosplastic particles in soil and water can significantly increase how much toxic chemicals plants and human intestinal cells absorb. Using a cellular model of the human small intestine, the researchers found that nano-size plastic particles increased the absorption of arsenic by nearly six-fold compared with arsenic exposure alone.

Engineers from Purdue University and GRIMM Aerosol Technik Ainring GmbH & Co. in Germany have found that chemical products from air fresheners, wax melts, floor cleaners, and deodorants can rapidly fill the air with nanoparticles that are small enough to get deep into our lungs. These nanoparticles form when fragrances interact with ozone, which enters buildings through ventilation systems.

Scientists from the U.S. Food and Drug Administration, Northwestern University, and the Illinois Institute of Technology have found evidence that silver nanoparticles embedded in packaging used as an antimicrobial agent were able to seep into the dry food the packaging is meant to protect. The scientists created samples of silver nanoparticles and embedded them in polyethylene film wraps, which could hold various types of food items. They tested wheat flour, slices of cheese, ground rice, and spinach leaves.

Researchers from Northwestern University have defined a method to tailor a sponge that is coated with nanoparticles to specific Chicago pollutants and then to selectively release them. In its first iteration, the sponge platform was made of polyurethane and coated with a substance that attracted oil and repelled water. The newest version is a highly hydrophilic (water-loving) cellulose sponge coated with nanoparticles tailored to other pollutants. The scientists found that by lowering the pH, metals flush out of the sponge.