Lifeboat Foundation

Molecular computer components could represent a new IT revolution and help us create cheaper, faster, smaller, and more powerful computers. Yet researchers struggle to find ways to assemble them more reliably and efficiently.

To help achieve this, scientists from the Institute of Physics of the Czech Academy of Sciences investigated the possibilities of molecular machine self-assembly building upon solutions honed by natural evolution and using synergy with current chip manufacturing.

There is a limit to the miniaturization of current silicon-based computer chips. Molecular electronics, using single-molecule-sized switches and memories, could provide a revolution in the size, speed and capabilities of computers while cutting down on their increasing power consumption, but their mass production is a challenge. Large-scale, low-defect, accessible nanofabrication and assembly of the components remains elusive. Inspiration taken from living nature could change this status quo.

A research team led by the late Professor Liang Haojun from the Hefei National Laboratory for Physical Sciences at the Microscale of University of Science and Technology of China (USTC) has developed a facile enthalpy-mediated strategy to precisely control the replication and catalytic assembly of DNA-functionalized colloids in a time-dependent manner, facilitating the creation of large-scale ordered nanomaterials. The study was published in Angewandte Chemie International Edition.

The replication of information is a fundamental characteristic of nature, with nucleic acids playing a crucial role in biological systems. However, creating synthetic systems that can produce large-scale, three-dimensionally ordered nanomaterials using self-replicating nanostructures has remained a formidable challenge.

Existing artificial self-replicating systems often fall short in programmable assembly into sophisticated nanostructures, limiting their potential functions and applications.

Self-assembling molecules that spontaneously organize themselves to form complex structures are common in nature. For example, the tough outer layer of insects, called the cuticle, is rich in proteins that can self-assemble.

Self-assembly is a cost-effective, environmentally sustainable and quick way of manufacturing nanostructures with critical applications in various industries, ranging from therapeutics to self-replicating machines.

Harnessing the self-assembling abilities of proteins from the cuticles of Asian corn borer moth caterpillars (Ostrinia furnacalis), Nanyang Technological University, Singapore (NTU Singapore) scientists have created nanosized capsules that could be used to deliver drugs and messenger RNA (mRNA). mRNA is a molecule that instructs cells to produce proteins and has been used in COVID-19 vaccines.

Using nanoparticles featuring anisotropic characteristics is a promising approach to developing multifunctional platforms for drug delivery and theranostics. This Review discusses methods to generate anisotropy in nanosystems and strategies to control particle transport, targeting and interaction with cells to overcome biological barriers.

Researchers at EPFL have created the first detailed model explaining the quantum-mechanical effects that cause photoluminescence in thin gold films, a breakthrough that could advance the development of solar fuels and batteries.

Luminescence, the process where substances emit photons when exposed to light, has long been observed in semiconductor materials like silicon. This phenomenon involves electrons at the nanoscale absorbing light and subsequently re-emitting it. Such behavior provides researchers with valuable insights into the properties of semiconductors, making them useful tools for probing electronic processes, such as those in solar cells.

In 1969, scientists discovered that all metals luminesce to some degree, but the intervening years failed to yield a clear understanding of how this occurs. Renewed interest in this light emission, driven by nanoscale temperature mapping and photochemistry applications, has reignited the debate surrounding its origins. But the answer was still unclear – until now.

Researchers discovered ferroelectricity in 2D vermiculite, boosting electric field responsivity in liquid crystals and paving the way for innovative large-scale displays.

Electro-optical liquid crystal (LC) device with wide applications is a cornerstone of the information society, which can continuously and dynamically modulate the light intensity, polarization, and phase retardation. An ancient theoretical insight proposes that a LC material with both an extremely large geometrical anisotropy and an inherent electric dipole is highly expected to improve the electric field responsivity of LCs.

However, neither commercial organic LC molecules nor R&D LC nanomaterials meet both aforementioned perquisites, while such LCs have not been reported so far. As for now, they are open questions for LC community about whether such an LC exists and the upper limit of its electric field responsivity.

It is a common hack to stretch a balloon out to make it easier to inflate. When the balloon stretches, the width crosswise shrinks to the size of a string. Noah Stocek, a PhD student collaborating with Western University physicist Giovanni Fanchini, has developed a new nanomaterial that demonstrates the opposite of this phenomenon.

Working at Interface Science Western, home of the Tandetron Accelerator Facility, Stocek, and Fanchini formulated two-dimensional nanosheets of tungsten semi-carbide (or W2C, a chemical compound containing equal parts of tungsten and carbon atoms) which when stretched in one direction, expand perpendicular to the applied force. This structural design is known as auxetics.

With the continual miniaturization of electronic devices, there is an urgent need to understand the electron emission and the mechanism of electrical breakdown at nanoscale. For a nanogap, the complete process of the electrical breakdown includes the nano-protrusion growth, electron emission and thermal runaway of the nano-protrusion, and plasma formation. This review summarizes recent theories, experiments, and advanced atomistic simulation related to this breakdown process. First, the electron emission mechanisms in nanogaps and their transitions between different mechanisms are emphatically discussed, such as the effects of image potential (of different electrode’s configurations), anode screening, electron space-charge potential, and electron exchange-correlation potential. The corresponding experimental results on electron emission and electrical breakdown are discussed for fixed nanogaps on substrate and adjustable nanogaps, including space-charge effects, electrode deformation, and electrical breakdown characteristics. Advanced atomistic simulations about the nano-protrusion growth and the nanoelectrode or nano-protrusion thermal runaway under high electric field are discussed. Finally, we conclude and outline the key challenges for and perspectives on future theoretical, experimental, and atomistic simulation studies of nanoscale electrical breakdown processes.

Light-driven molecular motors were first developed nearly 25 years ago at the University of Groningen, the Netherlands. This resulted in a shared Nobel Prize for Chemistry for Professor Ben Feringa in 2016. However, making these motors do actual work proved to be a challenge. A new paper from the Feringa lab, published in Nature Chemistry on 26 April, describes a combination of improvements that brings real-life applications closer.

First author Jinyu Sheng, now a postdoctoral researcher at the Institute of Science and Technology Austria (ISTA), adapted a “first generation” light-driven molecular motor during his Ph.D. studies in the Feringa laboratory. His main focus was to increase the efficiency of the motor molecule. “It is very fast, but only 2% of the photons that the molecule absorbs drive the rotary movement.”

This poor efficiency can get in the way of real-life applications. “Besides, increased efficiency would give us better control of the motion,” adds Sheng. The rotary motion of Feringa’s molecular motor takes place in four steps: two of them are photochemical, while two are temperature-driven. The latter are unidirectional, but the photochemical steps cause an isomerization of the molecule that is usually reversible.