As the world grapples with the growing problem of electronic waste (e-waste), researchers at Virginia Tech have made a groundbreaking discovery that could revolutionize the way we think about recycling. A new study published in Advanced Materials has developed a recyclable material that can make electronics easier to break down and reuse, offering a potential solution to the e-waste crisis.

The new material, created by two research teams led by Associate Professor of Mechanical Engineering Michael Bartlett and Assistant Professor of Chemistry Josh Worch, is a dynamic polymer called a vitrimer. This versatile material can be reshaped and recycled, combined with droplets of liquid metal that carry the electric current, similar to traditional circuit boards.

The benefits of this new material are numerous. It’s not only recyclable but also electrically conductive, reconfigurable, and self-healing after damage. This means that even if an electronic device is dropped or damaged, the circuit board can be easily repaired or recycled without losing its functionality.

Traditional circuit boards, on the other hand, are made from permanent thermosets that are incredibly difficult to recycle. The process of recycling them involves several energy-intensive deconstruction steps and still yields large amounts of waste. Billions of dollars’ worth of valuable metal components are lost in the process.

The Virginia Tech researchers have shown that their recyclable material can be easily deconstructed at its end of life using alkaline hydrolysis, enabling the recovery of key components such as liquid metal and LEDs. This closed-loop process could potentially reduce the amount of e-waste sent to landfills and conserve valuable resources.

While this breakthrough is a significant step forward in addressing the e-waste problem, it’s essential to note that the sheer volume of electronics being discarded by consumers is unlikely to be curbed entirely. However, by developing more sustainable and recyclable materials like the one described here, we can significantly reduce the environmental impact of electronic waste.

This research was supported by Virginia Tech through the Institute for Critical Technology and Applied Science and Bartlett’s National Science Foundation Early Faculty Career Development (CAREER) award. The findings have significant implications for industries such as electronics manufacturing, recycling, and materials science, highlighting the potential for innovation and collaboration to drive positive change in our world.

The development of ultra-high temperature ceramics has revolutionized the field of space and defense applications. Researchers have successfully demonstrated a new technique that uses lasers to create ceramics that can withstand extreme temperatures. This breakthrough has significant implications for various industries, including nuclear power technologies, spacecraft, and jet exhaust systems.

“Sintering is the process by which raw materials are converted into a ceramic material,” explains Cheryl Xu, co-corresponding author of a paper on this research and a professor of mechanical and aerospace engineering at North Carolina State University. “For this work, we focused on an ultra-high temperature ceramic called hafnium carbide (HfC). Traditionally, sintering HfC requires placing the raw materials in a furnace that can reach temperatures of at least 2,200 degrees Celsius – a process that is time-consuming and energy-intensive.”

The new technique works by applying a 120-watt laser to the surface of a liquid polymer precursor in an inert environment. The laser sinters the liquid, turning it into a solid ceramic. This process can be used to create ceramic coatings or complex three-dimensional structures.

One way engineers can make use of this technique is by applying ultra-high temperature ceramic coatings to materials that may be damaged by sintering in a furnace. Another method involves additive manufacturing, also known as 3D printing. In this approach, the laser sintering method can be used in conjunction with a technique similar to stereolithography.

In proof-of-concept testing, researchers demonstrated that the laser sintering technique produced crystalline, phase-pure HfC from a liquid polymer precursor. This achievement has significant implications for various industries where technologies must withstand extreme temperatures, such as nuclear energy production.

The researchers also demonstrated that laser sintering could be used to create high-quality HfC coatings on carbon-fiber reinforced carbon composites (C/C). The ceramic coating bonded well to the underlying structure and did not peel away. This is particularly useful for various applications, including hypersonic technologies like missiles and space exploration vehicles.

The new laser sintering technique has several advantages over conventional techniques. It allows for the creation of ultra-high temperature ceramic structures and coatings in seconds or minutes, whereas traditional methods take hours or days. The technique also uses significantly less energy and produces a higher yield, converting at least 50% of the precursor mass into ceramic, compared to the 20-40% conversion rate achieved by conventional approaches.

Lastly, the technique is relatively portable, requiring an inert environment but allowing for easier transportation of equipment compared to powerful, large-scale furnaces.

The researchers are excited about this advance in ceramics and are open to working with public and private partners to transition this technology for use in practical applications. The paper, “Synthesis of Hafnium Carbide (HfC) via One-Step Selective Laser Reaction Pyrolysis from Liquid Polymer Precursor,” is published in the Journal of the American Ceramic Society.

As scientists continue to push the boundaries of innovation, researchers at Tohoku University have made a groundbreaking discovery in the realm of electrocatalysis. They have successfully demonstrated that applying an external magnetic field can significantly enhance the performance of single-atom catalysts (SACs), leading to a staggering 2,880% improvement in oxygen evolution reaction magnetocurrent.

This revolutionary finding has far-reaching implications for various industries, particularly those involving ammonia production and wastewater treatment. Traditionally, electrocatalysis focused on tweaking the chemical composition and structure of catalysts. However, the introduction of magnetic-induced spin state modulation offers a new dimension for catalyst design and performance improvement.

By regulating the electronic spin state of the catalyst through an external magnetic field, researchers can precisely control the adsorption and desorption processes of reaction intermediates. This, in turn, reduces the activation energy of the reaction, allowing it to proceed more quickly. As explained by Hao Li of Tohoku University’s Advanced Institute for Materials Research (WPI-AIMR), “More efficient production processes can reduce costs, which may translate into lower prices for products such as fertilizers and treated water at the consumer level.”

The study employed advanced characterization techniques to confirm that the magnetic field causes a transition to a high spin state, which improves nitrate adsorption. Theoretical analysis also revealed the specific mechanics behind why this spin state transition enhances electrocatalytic ability.

In an experiment conducted with a Ru-N-C electrocatalyst exposed to an external magnetic field, researchers achieved a remarkable NH3 yield rate (~38 mg L-1 h-1) and a Faradaic efficiency of ~95% for over 200 hours. This represents a significant improvement compared to the same catalyst without the boost from an external magnetic field.

This groundbreaking work enriches our theoretical understanding of electrocatalysis by exploring the relationship between magnetic fields, spin states, and catalytic performance. The experimental results offer valuable insights for future research and development of new catalysts, paving the way for practical applications in electrochemical technologies.