Mechanical Engineering: Research Guide

Light still holds surprises—as demonstrated by researchers from the Ultrafast Phenomena Lab at the Faculty of Physics, University of Warsaw, in collaboration with the Institute of Low Temperature and Structure Research, the Polish Academy of Sciences, who have discovered a new enhancement effect in the emission of upconverting nanoparticles. They demonstrated that simultaneous excitation of these nanostructures with two near‐infrared beams of laser light leads to a significant increase in emission intensity.

Nanoparticles have diverse applications in modern science and industry, powering technologies like quantum-dot displays, nanocatalysts and drug delivery. Their unique physicochemical properties, which can be tuned by changing their size and shape, make them highly attractive.

Over the past decades, computer scientists have developed increasingly sophisticated sensors and machine learning algorithms that allow computer systems to process and interpret images and videos. This tech-powered capability, also referred to as machine vision, is proving to be highly advantageous for the manufacturing and production of food products, drinks, electronics, and various other goods.

Two-dimensional (2D) materials, thin crystalline substances only a few atoms thick, have numerous advantageous properties compared to their three-dimensional (3D) bulk counterparts. Most notably, many of these materials allow electricity to flow through them more easily than bulk materials, have tunable bandgaps, are often also more flexible and better suited for fabricating small, compact devices.

A joint study by researchers from the Technion Israel Institute of Technology and the University of Texas at Austin sheds new light on the structure of membranes used in water desalination. Published in ACS Nano, the study was selected as the journal's cover article.

Researchers at North Carolina State University have unveiled Rainbow, a first-of-its-kind multi-robot self-driving laboratory that autonomously discovers high-performance quantum dots—semiconductor nanoparticles critical for next-generation displays, solar cells, LEDs and quantum-engineering technologies.

A research team has developed a new material that can significantly enhance the lifetime and efficiency of quantum-dot light-emitting diodes (QLEDs), which is a next-generation display technology. Applying a high-binding-energy organic material, which is resistant to degradation under electrical and thermal stress, to the hole transport layer (HTL) is expected to contribute to developing next-generation QLEDs that can maintain brightness and stability over extended periods.

Waiting is the hardest part. Especially in the case of testing for water or food contamination, which can take days or even a week in some cases for the results, leaving the possibility that people have been unknowingly exposed.

Organic chemistry, the chemistry of carbon compounds, is the basis of all life on Earth. However, metals also play a key role in many biochemical processes. When it comes to "marrying" large, heavy metal atoms with light organic compounds, nature often relies on a specific group of chemical structures: porphyrins. These molecules form an organic ring; in its center, individual metal ions such as iron, cobalt, or magnesium can be "anchored."

Micro/nanorobots have progressed from science fiction to real-world applications in biomedicine, environmental remediation, and sensing. UA faculty member, Dr. Amir Nourhani is among 103 researchers worldwide contributing to an extensive mega-review titled "Technology Roadmap of Micro/Nanorobots," published in ACS Nano.

Polymers are essential in modern food packaging thanks to their low cost, light weight, flexibility, and chemical stability. They provide a crucial barrier to protect food from moisture, oxygen, sunlight, and microorganisms that cause spoilage and health risks. Among them, PET (polyethylene terephthalate) is especially valued for its transparency, stability, and strong mechanical properties.

A research team has developed upconversion nanoparticles to assist in powering molecular motors. The nanoparticles can convert near-infrared radiation, which is capable of penetrating bulk material, into blue or UV light that can efficiently power the motors. As a result, these motors can now be effectively used to make bulk materials responsive or act as molecular switches in biological applications. The results were published last month in the Journal of the American Chemical Society.

A study published in Molecules and led by researchers from the Changchun Institute of Optics, Fine Mechanics and Physics (CIOMP) of the Chinese Academy of Sciences demonstrated how deep learning can streamline the identification of atomic-scale defects in molybdenum disulfide (MoS2), a promising two-dimensional (2D) material for next-generation electronics.

Establishing robust isolated spins on solid surfaces is crucial for fabricating quantum bits or qubits, sensors, and single-atom catalysts. An isolated spin is a single spin that is shielded from external interactions. Because isolated spins can maintain their state for long periods, they are ideal for use as qubits, the basic units of quantum computation, and for ultrafast spintronic memory.

Whether in solar cells or in the human eye, whenever certain molecules absorb light, the electrons within them shift from their ground state into a higher-energy, excited state. This results in the transport of energy and charge, leading to charge separation and eventually to the generation of electricity.

Nanocarbon materials with pointed geometries, such as graphene and carbon nanotubes, are considered promising candidates as sources for field emission electrons. However, their practical application remains limited due to difficulties in controlling the orientation and arrangement of these materials.

Water still has unknown sides. When water is forced into two dimensions by enclosing it in appropriate materials, new properties, phase transitions, and structures emerge. MXenes as a class of materials offer a unique platform for exploring these types of phenomena. MXenes consist of transition metal carbides and nitrides with a layered structure whose surfaces can help them absorb water easily. The water forms an extremely thin film between the individual layers.

Half of the sun's radiant energy falls outside of the visible spectrum. On a cold day, this extra infrared light provides additional warmth to residential and commercial buildings. On a warm day, it leads to unwanted heating that must be dealt with through energy-intensive climate control methods such as air-conditioning.

Metal oxide materials with nanoscale pores have been applied and studied in a wide range of fields, including as catalysts, adsorption and separation materials, and energy materials. Among them, single-crystalline nanoporous metal oxides—with interconnected nanopores in a single crystal—are especially lucrative. They have recently attracted attention as unique materials that combine the desirable properties of nanoporous materials, such as high specific surface area and large pore volume, with those of single crystals.

When light hits solar cells, so-called electron-hole pairs are created: the electrons are excited and can move almost freely in the material—i.e. to generate electricity. The electrons will leave 'positive gaps," so-called holes, in the semiconductor material. They can also move through the material. Both electrons and holes carry an electrical charge. They deform the surrounding atomic lattice on their way through the material slightly.

A research team led by Prof. Huang Qing from the Ningbo Institute of Materials Technology and Engineering (NIMTE) of the Chinese Academy of Sciences has developed a new way to "edit" the internal layers of certain advanced materials, called MAX phases, in a breakthrough that could lead to entirely new kinds of two-dimensional (2D) layered materials with valuable technological uses.

Dr. Seon Joon Kim and his team at the Korea Institute of Science and Technology (KIST)'s Convergence Research Center for SEIF have developed a high-conductivity amphiphilic MXene material that can be dispersed in water, polar and nonpolar organic solvents.

Researchers at the Cavendish Laboratory, University of Cambridge have demonstrated a new way to control radiation in the terahertz range—an often-overlooked part of the electromagnetic spectrum—with unprecedented dynamic range and speed. The findings could open the door to advanced technologies in communications, imaging, and sensing and mark major progress in the development of practical devices that operate in the terahertz range.

When two mesh screens or fabrics are overlapped with a slight offset, moiré patterns emerge as a result of interference caused by the misalignment of the grids. While these patterns are commonly recognized as optical illusions in everyday life, their significance extends to the nanoscale, such as in materials like graphene, where they can profoundly influence electronic properties.

In the world of nanotechnology, seeing clearly isn't easy. It's even harder when you're trying to understand how a material's properties relate to its structure at the nanoscale. Tools like piezoresponse force microscopy (PFM) help scientists peer into the nanoscale functionality of materials, revealing how they respond to electric fields. But those signals are often buried in noise, especially in instances where the most interesting physics happens.

Researchers at Beijing University of Technology have developed a new type of acid-stable bimetallic phosphide-silver core-shell nanowire catalyst that significantly improves the efficiency of the hydrogen evolution reaction (HER).

Researchers with the schools of science and engineering at Rensselaer Polytechnic Institute (RPI) are exploring new ways to manipulate matter with light to unlock a new generation of computer chips, photovoltaic cells and other advanced materials.

Graphite has attracted global interest due to its unique anisotropic properties, including excellent electrical and thermal conductivity. Widely used as a battery anode material and in applications such as electromagnetic shielding, catalysis, and nuclear technology, graphite remains a critical material in both industrial and research fields.

Sliding ferroelectrics are a type of two-dimensional (2D) material realized by stacking nonpolar monolayers (atom-thick layers that lack an electric dipole). When these individual layers are stacked, they produce ferroelectric materials with an intrinsic polarization (i.e., in which positive and negative charges are spontaneously separated), which can be switched using an external electric field that is perpendicular to them.

Scientists have created a new way to characterize graphene oxide (GO) more cheaply and quicker than ever before, helping get the emerging technology out of the lab and into the market.