Behind the buzz and beyond the hype:
Our Nanowerk-exclusive feature articles
Zinc oxide (ZnO) is considered a workhorse of technological development exhibiting excellent electrical, optical, and chemical properties with a broad range of applications as semiconductors, in optical devices, piezoelectric devices, surface acoustic wave devices, sensors, transparent electrodes, solar cells, antibacterial activity etc. Thin films or nanoscale coating of ZnO nanoparticles on suitable substrates are viewed with great interest for their potential applications as substrates for functional coating, printing, UV inks, e-print, optical communication (security-papers), protection, barriers, portable energy, sensors, photocatalytic wallpaper with antibacterial activity etc. Various methods like chemical, thermal, spin coating, spray pyrolysis, pulsed laser deposition have been used for thin film formation but they are limited to solid supports such as metal, metal oxides, glass or other thermally stable substrates. Coating of ZnO nanoparticles on thermolabile surfaces is scarce and coating on paper was yet to be reported. Paper as a substrate is an economic alternative for technological applications having desired portability and flexibility. Researchers from the National Tsing Hua University in Taiwan found a way of coating paper with ZnO nanoparticles using ultrasound.
With the advent of nanoscience and technology, a new area has developed in the area of textile finishing called "Nanofinishing". Growing awareness of health and hygiene has increased the demand for bioactive or antimicrobial and UV-protecting textiles. Coating the surface of textiles and clothing with nanoparticles is an approach to the production of highly active surfaces to have UV blocking, antimicrobial, flame retardant, water repellant and self-cleaning properties. While antimicrobial properties are exerted by nano-silver, UV blocking, self-cleaning and flame-retardant properties are imparted by nano-metal oxide coatings. Zinc oxide (ZnO) nanoparticles embedded in polymer matrices like soluble starch are a good example of functional nanostructures with potential for applications such as UV-protection ability in textiles and sunscreens, and antibacterial finishes in medical textiles and inner wears.
The discussion about the health scare caused by the Magic-Nano sealing spray (which, as it turned out, was neither magic nor nano - see this article) has barely ebbed when questions about another nano consumer product arise. This time, it is not a health scare but rather the opposite - alleged health benefits of nanoparticles.
The use of nanoparticles in sunscreens is one of the most common uses of nanotechnology in consumer products. Well over 300 sunscreens on the market today contain zinc oxide or titanium oxide nanoparticles.
An electrochromic display is one of the most attractive candidates for paper-like displays, so called electronic paper, which will be the next generation display, owing to attributes such as thin and flexible materials, low-power consumption, and fast switching times.
Researchers from the Zhengzhou Institute of Aeronautical Industry Management have developed a set of techniques to reduce the high cost of fabricating carbon nanotube field emission displays.
Researchers have turned to carbon nanotubes to create a new class of large area, high resolution, low cost flat panel displays. Some believe field emission display (FED) technology, utilizing carbon nanotubes (CNT) as electron emitter, will be the biggest threat to LCD's dominance in the panel display arena.