Effect of nanotechnology instructions on senior high school students

Senior High School Teaching Conception of Nanotechnology

Nanometer (nm) is the hottest noun in the 21 century. A nanometer, which we can’t see with eyes and touch with hands, is equivalent billions of a meter under high resolution microscopy techniques. There is a lot of nano phenomena exist in nature, like gecko effect, nanotechnology magnetic navigation, photonic crystals, and moth eye effect etc. The most famous is the "Lotus effect." For example when water droplet drops on the lotus leaf, instead of spread out the droplets, it gathers together. The secret of why lotus leaf surface can gather the droplets is because the surface of lotus leaf has nano composition villus on it which makes the contact angle between water and leaf greater than 120 degrees. Therefore, when the leaf tilts a little, the droplets will roll away from the leaf surface and bring dirty dust away (Su, 2003). The origin concept of “Biological compass” is that scientist found nano-magnetic particles in some of the organism. These organisms can recognise the direction under the help of its nano-magnetic particles and geomagnetic field and can be used as a navigation system (Lu, &Sung, 2010). Another nano phenomenon “Nano Photocatalyst” comes from observing scales on butterfly wings. The scales are periodic structures and have around 10 to 12 layer thick. These nano-size periodic structures are the reason why butterflies can have dazzling color on their wings. Nano Photocatalyst is a periodic structure material that can interact with light, as the example in optical fiber and optical waveguide (Drane, Swarat, Light, Hersam, & Mason, 2009). We inquire into some nano photocatalyst product and found its titanium dioxide (TiO2) material which will produce electron will react with water and oxygen. When generates reactive hydroxyl radicals (OH-), peroxynitrite root Radical (HO2-) and superoxide ion radicals (O2-) react with water and oxygen, the electron hole will illuminated. These free radicals have the ability to decompose organic compounds.(Lu, et al., 2010) Gecko effect is also a nano phenomenon, which starts form watching gecko walking on the ceiling. Millions of spatula tipped setae on gecko footpads have spatula-like structures tiny cilium at the pointed end of the toes. Each seta provides a little attractive force, adding millions of them allow the attractive forces adsorb 120 kilogram on the surface (Lee, Lee, & Messersmith, 2007). In addition, there are a lot of nanotechnology products; for example, target drugs for cancer therapy is using gold nanoparticles to target organs and then kill the cancer cell to attain the effect of therapy with heat treatment (Xue, Lu, Wu, & Zeng, 2008).

The nanotechnology declarative knowledge statements and the teaching standards

Nanotechnology expert concept map of senior high school shows the declarative knowledge statements:

The definition of nanotechnology: Nanotechnology is define as using ways to combine materials, compositions, structures in between 1-100 nm, and emerge into new features and phenomena.

Natural phenomena: For example, the setae spatula on gecko's feet is a kind nano structure, which can form into van der Waals force and enhance the force between the surfaces it contacts.

Nanotechnology products: For example, we use hydrophobic of lotus effect to make cloth that is anti-pollution such as nano-necktie.

Skills development: Using barker ball to coat target drugs and the functional group on barker ball surface will be acidulated or alkalized, which is ease to pass though gastrointestinal and find the main organ that need to be treated.

Affective attitude: For example, we should pay attention to new types of pollutants, which is produced by new nanotechnology product and might cause lung disease if we inhale it (Lu & Sung, 2010).