Question #1: Calculate the increase in surface area for the following conditions:
- A spherical particle with a radius of 100 to be reduced to a group of particles with 10 nm radius
- A cylindrical wire with a radius of 100 and a length of 100 to be reduced to a group of wires with 10 nm radius and 100 nm length.
- A cube particle with a length of 100 to be reduced to a group of cubes with 10 nm length
Question #2: Estimate the ratio of surface to bulk atoms in following conditions:
- Spherical clusters – for cluster of radii 1) 5 , 2) 500 nm, 3) 1 nm.
- Cubic clusters – for cluster of length 1) 5 , 2) 500 nm, 3) 1 nm.
In typical metals the surface atom layer has a thickness of 2 .
Question #3: The reaction for the deposition of on the surface is:
Gallium nitride (GaN) is an important wide-band-gap semiconductor. Propose a chemical reaction for the deposition of GaN.
Question #4: How long will it take for the spherical particles in Table 1 to settle, at their terminal velocities under free-settling conditions, through 2 m of water at 20?
Question #5: Explain the applications of thin films in the fields of energy and environment?