Mechanical Engineering: Research Guide

Controlled manipulation of fibers that are as thin as or even thinner than human hair is a real challenge. Despite technological development, the precise and reversible change of the microfibers' orientation is not easy. The interdisciplinary team of researchers from the Institute of Physical Chemistry, Polish Academy of Sciences, has recently developed a way to control the shape of microfibers with electricity. This brings us closer to a novel technical solution in micromechanics and soft robotics.

Bacteriophages are viruses that can kill bacteria through highly specific interactions. While this property can be beneficial in selected applications, bacteriophages represent a serious threat to laboratories and industries that rely on bacterial cultures for production. Their selective inactivation remains a major challenge. Recently, researchers from the Institute of Physical Chemistry, Polish Academy of Sciences in Poland, demonstrated an innovative solution that enables targeting the surface of bacteriophage through electrostatic interactions as a promising strategy for their inactivation without adversely affecting bacterial strains or eukaryotic cells.

Physicists in Leiden have built a microscope that can measure no fewer than four key properties of a material in a single scan, all with nanoscale precision. The instrument can even examine complete quantum chips, accelerating research and innovation in the field of quantum materials. The study is published in the journal Nano Letters.

DNA, the blueprint of life, is best known for its fundamental role as genetic material—storing and transmitting biological information through the precise sequence of its bases. For decades, this information-storage function has defined how we think about DNA. But what if DNA could do more than encode life? What if it could act as a reaction vessel that precisely guides and controls specific chemical reactions?

Ammonia (NH3)—the second-most-produced chemical globally—has proven to be highly important in furthering human civilization over the centuries, both in terms of technological capabilities and innovation potential. It is widely utilized in fertilizers, refrigerants, biomarkers, and next-generation fuel. Unfortunately, NH3 is highly toxic, resulting in complications such as respiratory irritation, chest pain, pulmonary edema, and even death. This makes effective and rapid NH3 sensing and detection capabilities indispensable in industries or environments prone to NH3 leaks.

Probing the vibration of atoms provides detailed information on local structure and bonding that define material properties. Tip-enhanced Raman spectroscopy (TERS) offers extremely high resolution to probe such vibrations. Krystof Brezina and Mariana Rossi from the MPI for the Structure and Dynamics of Matter (MPSD), and Yair Litman from the MPI for Polymer Research (MPIP), have demonstrated that realistic, first-principles simulations are essential for interpreting TERS images of molecules and materials on surfaces. Their approach reveals how interactions with metallic substrates reshape vibrational imaging at the nanoscale. The work has now been published in ACS Nano.

The performance and stability of smartphones and artificial intelligence (AI) services depend on how uniformly and precisely semiconductor surfaces are processed. KAIST researchers have expanded the concept of everyday "sandpaper" into the realm of nanotechnology, developing a new technique capable of processing semiconductor surfaces uniformly down to the atomic level.

Researchers in China have isolated the effects of electronic friction, showing for the first time how the subtle drag force it imparts at sliding interfaces can be controlled. They demonstrate that it can be tuned by applying a voltage, or switched off entirely simply by applying mechanical pressure. The results, published in Physical Review X, could inform new designs that allow engineers to fine-tune the drag forces materials experience as they slide over each other.

From table salt to snowflakes, and from gemstones to diamonds—we encounter crystals everywhere in daily life, usually cubic (table salt) or hexagonal (snowflakes). Researchers from Noushine Shahidzadeh's group at the UvA Institute of Physics now demonstrate how mesmerizing spherical crystal shapes arise through structures called spherulites.

The global development of civilization diseases is a challenge that requires many modern solutions, not only in terms of treatment, but first and foremost in terms of early diagnostics. One of the highly sensitive methods enabling fast identification of even ultralow concentrations of biomarkers or drugs in complex samples with high accuracy is surface-enhanced Raman spectroscopy (SERS).

In nanoscale particle research, precise control and separation have long been a bottleneck in biotechnology. Researchers at the University of Oulu have now developed a new method that improves particle separation and purification. The promising technique could be applied, for example, in cancer research.

A novel type of three-dimensional (3D) polar topological structure, termed the "polar chiral bobber," has been discovered in ferroelectric oxide thin films, demonstrating promising potential for high-density multistate non-volatile memory and logic devices. The result was achieved by a collaborative research team from the Institute of Metal Research (IMR) of the Chinese Academy of Sciences, the Songshan Lake Materials Laboratory, and other institutions. The findings were published in Advanced Materials on January 30.

An international team of researchers has developed a breakthrough method for producing MXenes—an important family of two-dimensional materials—with unprecedented purity and control. The new "gas–liquid–solid" process enables the synthesis of pure MXenes with uniformly distributed halogen atoms on the surface and a precisely tunable surface composition. The method dramatically boosts their electrical conductivity and opens the door to high-performance electronics, sensors, and energy technologies.

As artificial intelligence advances, computers demand faster and more efficient memory. The key to ultra-high-speed, low-power semiconductors lies in the "switching" principle—the mechanism by which memory materials turn electricity on and off. A South Korean research team has successfully captured the elusive moment of switching and its internal operational principles by momentarily melting and freezing materials within nano-devices—phenomena that were previously difficult to observe. The study provides a foundational blueprint for designing next-generation memory materials that are faster and consume less power based on fundamental principles.

A research team affiliated with UNIST has developed stable and efficient chalcogenide-based photoelectrodes, addressing a longstanding challenge of corrosion. This advancement paves the way for the commercial viability of solar-driven water splitting technology—producing hydrogen directly from sunlight without electrical input.

In collaboration with international partners, researchers at the University of Stuttgart have experimentally demonstrated a previously unknown form of magnetism in atomically thin material layers. The discovery is highly relevant for future magnetic data storage technologies and advances the fundamental understanding of magnetic interactions in two-dimensional systems. The results have now been published in Nature Nanotechnology.

MXene materials are promising candidates for a new energy storage technology. However, the processes by which the charge storage takes place were not yet fully understood. A team at HZB has examined, for the first time, individual MXene flakes to explore these processes in detail. Using the in situ Scanning transmission X-ray microscope "MYSTIIC" at BESSY II, the scientists mapped the chemical states of titanium atoms on the MXene flake surfaces. The results revealed two distinct redox reactions, depending on the electrolyte. This lays the groundwork for understanding charge transfer processes at the nanoscale and provides a basis for future research aimed at optimizing pseudocapacitive ener..

Researchers at University of Jyväskylä (Finland) advance understanding of gold nanocluster behavior at elevated temperatures using machine learning-based simulations. This information is crucial in the design of nanomaterials so that their properties can be modified for use in catalysis and other technological applications.

Ammonia, a key part of nitrogen fertilizers, is central to sustaining global food production. However, its manufacture is also energy intensive: Ammonia production requires 2% of global energy to meet global demand. Approximately 170 million metric tons (50%) of the global supply of ammonia is produced by the Haber-Bosch process, a common industrial process. Biological nitrogen fixation produces the other 50% of the global ammonia supply.

Two-dimensional (2D) materials promise revolutionary advances in electronics and photonics, but many of the most interesting candidates degrade within seconds of air exposure, making them nearly impossible to study or integrate into real-world technology. Transition metal dihalides represent a particularly compelling yet challenging class of materials, with predicted properties ideal for next-generation devices, but their extreme reactivity when exposed to air prevents even basic structural characterization.

A research team led by Professor Youngwook Kim from the Department of Physics and Chemistry, DGIST, in collaboration with the research team of Professor Gil Young Cho at KAIST, have discovered a new memory principle that enables information to be written and erased electrically by stacking ultrathin materials, such as graphene, in a sandwich-like structure.

As the miniaturization of silicon-based semiconductor devices approaches fundamental physical limits, the electronics industry faces an urgent need for alternative materials that can deliver higher integration and lower power consumption. Two-dimensional (2D) semiconductors, which are only a single atom thick, have emerged as promising candidates due to their unique electronic and optical properties. However, despite intense research interest, controlling the growth of high-quality 2D semiconductor crystals has remained a major scientific and technological challenge.

Gas vesicles are among the largest known protein nanostructures produced and assembled inside microbial cells. These hollow, air-filled cylindrical nanostructures found in certain aquatic microbes have drawn increasing interest from scientists due to their potential for practical applications, including as part of novel diagnostic and therapeutic tools. However, producing gas vesicles is a difficult task for cells in the lab, hindering the development of applications.

By changing the physical structure of gold at the nanoscale, researchers can drastically change how the material interacts with light—and, as a result, its electronic and optical properties. This is shown by a study from Umeå University published in Nature Communications.

When water and ions move together through channels only a nanometer wide, they behave in unusual ways. In these tight spaces, water molecules line up in single file. This forces ions to shed some of the water molecules that normally surround them, leading to the unique physics of ion transport. Biological channels are especially adept at this behavior, often choreographing channel openings and closings to achieve complex behaviors such as signals in the nervous system.

Researchers at the University of Maine and the U.S. Department of Energy's (DOE) Oak Ridge National Laboratory (ORNL) are collaborating on a new way to dry non-aggregated cellulose nanofiber—a material that could replace plastics in a wide range of products.

The precise control of tiny droplets on surfaces is essential for advanced manufacturing, pharmaceuticals, and next‐generation lab‐on‐a‐chip diagnostics. However, once droplet volume reaches pico- and nanoliter scales, the droplets become extremely sensitive to microscopic surface irregularities, and friction at the solid‐liquid interface becomes a major obstacle to smooth transport.

In a breakthrough that could power next-generation electronics, sensors, and energy storage devices, CMU engineers have developed a fabrication technique that arranges MXene nanosheets, each a million times thinner than a sheet of paper, into complex 3D structures in just a single printing step.

A surface capable of responding to chemical signals generated by microorganisms and automatically producing biocidal substances—this is not a futuristic vision, but a description of how the B-STING silica nanocomposite works. The new material, developed at the Institute of Nuclear Physics Polish Academy of Sciences in Cracow, acts as a nanofactory of reactive oxygen species, activating itself only when necessary.

Researchers from Drexel University who discovered a versatile type of two-dimensional conductive nanomaterial called MXene nearly a decade and a half ago, have now reported on a process for producing its one-dimensional cousin: the MXene nanoscroll. The group posits that these materials, which are 100 times thinner than human hair yet more conductive than their two-dimensional counterparts, could be used to improve the performance of energy storage devices, biosensors and wearable technology.