Nanotechnology Spotlights

Pufferfish inspires solar-driven water purification

Although solar-driven water evaporation using sunlight is a promising sustainable strategy, the water production rate via solar technologies remains insufficient to meet practical demands. Addressing this issue, researchers have developed a solar absorber gel to purify water from contaminated sources using only natural sunlight. The hydrogel can force liquid water out of the gel via phase transition when the sun warms the...

Apr 13, 2021

An inverse-designed metalens 3D-printed on an optical fiber tip

A new generation of lenses - metalenses - is starting to replace bulky curved lenses with simple, flat surfaces that use nanostructures to focus light. These flat surfaces - meatsurfaces - have enabled the design of diffraction-based flat devices to replicate the functionalities of conventional lenses with sub-wavelength or few-wavelength thicknesses. Researchers have now successfully designed and experimentally demonstrated...

Apr 08, 2021

Observing thermal transport in carbon nanotube bundles

Individual single-walled carbon nanotubes (SWCNTs) have thermal conductivity that is several times higher than copper. However, once researchers start to assemble SWCNTs into macroscale composites, fibers or films, they notice that thermal conduction drops significantly. Employing in situ transmission electron microscopy, researchers visualized a colossal anisotropy of thermal conductivity of nanoscale materials. The team...

Apr 06, 2021

A wearable, wireless feedback sensor system to track body conditions

Wearable flexible sensors have recently emerged as promising alternatives for human healthcare monitoring due to their lightweight and thin-film-based nature. However, few of these flexible sensor systems are applicable to neonatal monitoring, especially sleeping posture detection. Researchers now report a versatile laser-induced-graphene-based integrated sensor system, which can wirelessly monitor sleeping postures, respiration...

Mar 31, 2021

Ultrasensitive and label-free chirality detection of diabetes-related metabolic molecules

Researchers demonstrate label-free chiral detection of metabolic molecules at picomolar level through microbubble-induced rapid accumulation of biomolecules on plasmonic chiral sensors, which shows a 10-million times enhancement in sensitivity comparing to state-of-the-art plasmonic chiral sensors. The researchers achieved their ultrahigh sensitivity in chiral sensing of biomolecules by utilizing two enhancement mechanisms:...

Mar 30, 2021

Real-time sweat analysis with wearable microfluidic sensors

Researchers have demonstrated the large-scale fabrication of skin-interfaced printed microfluidic patches, capable of multiplexed electrochemical detection of biomarkers from human sweat. This sensor continuously and simultaneously measures the level of biomarkers such as lactate, Na+, K+, and pH during sweating. The skin-worn sensor can selectively measure analytes even in the presence of other interfering species present...

Mar 29, 2021

A disposable living laser printed on chip for drug screening

Scientists have created a new way to monitor subtle drug interactions between bacteria and antibiotics. By using a common office inkjet printer, researchers developed a disposable living laser on chip by encapsulating living bacteria inside. Strong laser emissions generated from bacteria inside the droplet will be dramatically enhanced during drug interactions. This breakthrough could enable more sensitive and high-throughput...

Mar 25, 2021

New theory unveils obscure nonvolatile resistive switching in 2D materials

Nonvolatile resistive memory (NVRM), also called a 'memristor', is an emerging technology that offers the possibility of in-memory computation and thus holds promise to overcome the von Neumann bottleneck. NVRM is a two-terminal device but, unlike an ordinary resistor, it exhibits hysteresis in input-output characteristics and thus can be also be used as memory. A new theory suggests that such resistive switching is an intrinsic...

Mar 24, 2021

Toward perdurable flexible electronics

In order to realize practical device applications of stretchable strain sensors, stability without sacrificing sensitivity, stretchability, and scalability is crucial. To that end, researchers report a kirigami-structured graphene-polymer hybrid nanocomposite for strain sensors by a laser direct writing technique on a polyimide sheet. The approach of laser direct writing not only contributes to the conversion of polyimide...

Mar 23, 2021

Understanding ionic phenomena in liquid crystals doped with nanoparticles

Liquid crystal materials are ubiquitous in everyday life. Recently, a new way to create advanced liquid crystal materials by merging nanotechnology and liquid crystals was discovered: by adding nanoscale objects to liquid crystals, new materials with superior physical properties can be created. However, this raises an important question: How do nanoparticles affect ionic processes in liquid crystals? Here is an overview of...

Mar 18, 2021