Science in Hong Kong: Volume 2, Spring 2005 p1
Nanotechnology
by Sin Ka Man
Introduction
Hong Kong (H.K), a place with a land area of only 1100km 2 [1], but with a population of 6 974 800
[2],
is
one of the most populated areas in the world. Although there are numerous plans to increase space
for use, such as reclamation and building skyscrapers, they cannot quite cope with the expanding
population and cause many environmental problems. If there are difficulties in increasing land area,
will it possible to reduce “our” problems to accommodate for the limited living space? Nanotechnology
may be the solution.
Nanometer (nm) – an International System of Units (SI) for measurement, is equal to about
1/1,000,000,000 of a meter (10-9m)
[3].
If the Earth’s diameter is 1 meter, then the diameter of a small
aggie will be one nanometer [4]. The technology that study matters on the nanoscale (1nm to 100nm) is
termed nanotechnology. Nanotechnology is recognized as the new industrial revolution because
findings in nanotechnology are completely novel to existing theories and technology. It could be seen
that the physics of materials in nanoscale is very different from that of the normal size [4]. For example,
according to recent research, gold in normal size is yellow in color while gold in nanoscale appears to
be red
[4];
the conductivity of Titanium oxide in nano size is twice that of the normal size
[3].
All these
exciting findings make nanotechnology a very active research area in the scientific field.
Nanotechnology is still very young, only about a decade old. But Hong Kong, being a knowledgebased economy, has already started research in this area and made excellent achievements such as
the discovery of the world’s smallest single-walled carbon nanotubes by the Hong Kong University of
Science and Technology (HKUST)
[5,6].
Also, a motion that encourages the development of
nanotechnology in Hong Kong was proposed in the Legislative Council in 2001
[1].
Nanotechnology
was even identified as one of the technology areas that Hong Kong has comparative advantages in
and has potential for meeting industry and market needs, in the consultation paper by the Innovation
and Technology Commission in June 2004 [7].
Take one of the inventions by the Chinese University of Hong Kong (CUHK) as example. CUHK
manipulated nanotechnology and successfully applied it to daily lives in 2002. That was the first time
for nanotechnology to become a commercial product in Hong Kong. CUHK has developed an
advanced technology known as Photocatalytic Oxidation (NanoPCO) by nanotechnology. This
technology involves deposition of nanoscale titanium dioxide on a solid substrate. As the coating
exhibits strong photocatalytic activity under ultraviolet radiation, most organic, inorganic pollutants and
bacteria are oxidized on the substrate. This technology was proposed to be used in areas like water
quality treatment and air purification
[8].
Science in Hong Kong: Volume 2, Spring 2005 p2
NanoPCO has been proven to be more efficient than the conventional UV irradiation. It can kill
bacteria such as E.coli and Vibrio cholerae in an instant. Many local seafood restaurants have been
using this new technology for water treatment due to its simplicity, efficiency and low costs. By using
NanoPCO, the risk of taking contaminated seafood or water can be dramatically reduced. Moreover, if
sewage were to be treated and sterilized by NanoPCO prior to discharge into the ocean, the ecology in
the ocean can be definitely safeguarded. Furthermore, once polluted-air is filtered by engineered
photocatalytic modules, air-borne environmental health risks and the likelihood of infection by
respiratory and cardio-pulmonary diseases can be greatly reduced. The community would benefit in
health and hygiene through nanotechnology [8].
In addition to local universities research, a Hong Kong based company pioneering in the research and
development of nanotechnology has also made many applications of nanotechnology in daily lives
[9].
It made use of nanotechnology to cut metal silver into ultra-small nanoscale silver, about 10nm in
diameter. It has been proven that nanoscale silver can kill germs more efficiently that normal silver.
Thus nanoscale silver is used to produce surgical masks, dressings in medical care and yarn in the
textile industry [9].
Although reducing our problems may not be possible at this stage, it is still believed that applications
of nanotechnology will have a significant impact on human lives in the future. Hong Kong should make
use of the advantage of standing on the leading edge of nanotechnology research field at the moment
by promoting nanotechnology.
References
1. Legislative Council, 2001 from http://www.yeungyiuchung.org.hk/debate/yy072.htm accessed
on 20 Oct 04
2. Lands Department, Hong Kong, 2004 from http://www.landsd.gov.hk accessed on Oct 04
3. “What is Nanotechnology” from http://www.edinformatics.com/technology/nano_intro.htm
accessed on 21 Oct 04
4. Official Homepage of TAINANO, INC from http://www.tainano.com/ accessed on 21 Oct 04
5. Press Release by HKUST, 2001 “HKUST Scientists Discover Superconductivity in World’s
Smallest Single-Carbon Nanotubes” from
http://www.ust.hk/~webopa/news/2001_News/news0703.html accessed on 21 Oct 04
6. Press Release by HKUST, 2000 “HKUST Develops the World’s Smallest Single-Walled
Carbon Nanotubes” from http://www.ust.hk/%7Ewebopa/news/2000_News/news1102b.html
accessed on 21 Oct 04
7. Consultation Paper of Innovation and Technology Commission, 2004 “New Strategy of
Innovation and Technology Development” from
http://www.info.gov.hk/itc/eng/itconsultation/consultation_paper_e.pdf accessed on 21 Oct 04
8. Press Release by CUHK, 2002 “CUHK Research in Nanotechnology Serves the Community”
from http://www.cuhk.hk/ipro/021007c.htm accessed on 21 Oct 04
Science in Hong Kong: Volume 2, Spring 2005 p3
9. Official Homepage of ANSON Nanotechnology Group Co. Ltd. from
http://www.ansonano.com/ accessed on 21 Oct 04
10. Census and Statistics Department, Hong Kong, 2004 from http://www.censtatd.gov.hk
accessed on 20 Oct 04