Paper electronics - putting flexible electronic sensors and other circuits on regular paper - have the potential to cut the price of a wide range of medical tools, from point-of-care diagnostic tests to portable DNA detectors. In new work, researchers have now shown an integration strategy to rationally design an ultra-low cost health monitoring device, a Paper Watch, using recyclable household materials: non-functionalized papers.
Researchers have developed a highly manufacturable deep reactive ion etching based process involving a hybrid soft/hard mask process technology that shows high aspect ratio complex geometry Lego-like silicon electronics formation enabling free-form (physically flexible, stretchable, and reconfigurable) electronic systems. This hybrid mask enables deep sub-millimeter etching while preserving existing devices and structures and is advantageous for many applications, including lego like concept for pre-packaging modules/system integration.
Compact optical components are crucial to realize miniaturized optical systems and integrated optoelectronic devices. Plasmonic metasurfaces - structured materials in 2D with rationally designed, subwavelength-scale building blocks - have drawn great interest because they can control light based on subwavelength structures. These planar devices are attractive for applications ranging from high resolution imaging to 3D holography. New work describes the design and prototyping of single-crystalline TiN plasmonic metasurfaces based on subwavelength hole arrays.
Liquid crystals used in modern devices such as laptops, tablets and smartphones typically contain a small fraction of ionic contaminants. These ion contaminants can originate from multiple sources during the chemical synthesis of materials, in the process of assembling the device, and in its daily use.
In the case of LCDs, mobile ions in liquid crystals lead to such undesirable effects as image sticking, image flickering, and slow response. A promising solution to reduce the concentration of mobile ions in liquid crystal devices can be found by merging liquid crystals and nanotechnology.
Frost and ice accumulation result in significant decreases in the performance of ships, wind turbines, and heat exchangers. The use of active chemical, thermal, and mechanical methods of ice removal is time consuming and costly in operation. The development of passive methods to inhibit condensation, frost and ice formation is an attractive alternative. Examples are anoengineered anti-frost and anti-icing superhydrophobic and lubricant impregnated surfaces.
Paper, probably the cheapest and most widely used flexible and eco-friendly material in daily life, is a promising substrate for making flexible devices ranging from electronics to microfluidics, energy storage and sensors. In new work, researchers have developed a new and reliable method to achieve conformal coating of individual cellulose fibers in the paper and the fabrication of a metal electrode via patterning of gold and silver layers on the coated paper.
Lanthanide dopants play an important role in desirable phase transformations of aluminum oxide (alumina) in order to achieve optimized physical and chemical properties. For example, the presence of dopants strengthens the grain boundaries of alumina, largely affecting its mechanical properties. New research indicates that there are significant structural changes to the lattice with addition of the dopant, and that understanding these effects will lead to future research for addressing these challenges.
Maximizing light absorption of nanomaterials has been an emerging research field in the recent years due to its attractiveness in a wide range of applications that involves conversion or utilization of solar energy. However, most of the concepts reported are based on multi-layered architecture inspired by optical impedance matching concepts that requires complicated non-scalable fabrication process such as electron beam lithography. Efforts on maximizing light absorption via nanostructuring remain scarce. Researchers have now reported such a material - a nanolayer of black gold.