Transcript Nano

NANOMATERIALS
纳米材料学
刘轶 (Yi Liu)
材料科学与工程学院
上海理工大学
School of Materials Science and Engineering
University of Shanghai for Science and Technology
Course information
时间地点： 2012-2013第二学期，1-16周
周一7-8节和单周周三7-8节，三教116
课程性质：2010级材料科学与材料成型本科生选修
学时学分：48学时/3学分
考查方式：出勤(10%)+作业(50%)+论文(20%)+演讲(20%)
QQ group: 124345642
TAs: 张法达(Fada Zhang) , 汪秀南(Xiunan Wang)
Student representatives:田采焕
Textbook：NANOSTRUCTURES & NANOMATERIALS:
Synthesis, Properties & Applications (2nd edition, 2011)
Authors：Prof. Guozhong Cao, University of Washington, USA
Press：Imperial College Press
《纳米结构和纳米材料》
— 合成、性能及应用
高等教育出版社，2011
Guozhong Cao, Ying Wang 著；董星龙译
Where to find?
Other books on nanomaterials
纳米材料和纳米结构，张立德和牟季美，科学出版社, 2011
纳米材料基础与应用，林志东，北京大学出版社，2010
纳米材料科学导论（第二版），陈敬中等，高等教育出版
社，2010
Nanostructures: Theory and Modeling, C. Delerue and M.
Lannoo, Springer 2004; 科学出版社影印本，2008
纳米材料物理基础，张邦维，化学工业出版社，2009
Handbook of Nanoscience, Engineering, and Technology
(3rd edition), W. A. Goddard etc., CRC press, 2012
Note: Nanoscience and nanotechnology are still
under very active development.
Syllabus
Chapter 1. Introduction 引言
Chapter 2. Physical chemistry of solid surface 固态表面的物理化学
Chapter 3. Zero-dimensional nanostructures: nanoparticles 纳米粒子
Chapter 4. One-dimensional nanostructures: nanowires 纳米线
Chapter 5. Two-dimensional nanostructures: thin films 薄膜
Chapter 6. Special nanomaterials 特殊纳米材料
Chapter 7. Nanostructures fabricated by physical techniques 物理制备法
Chapter 8. Characterization and properties of nanomaterials 表征和性能
Chapter 9. Applications of nanomaterials 纳米材料的应用
Chapter 1 Introduction
Concept of sizes
1 nm = 10 -9 m （one billionth）
length of linear chain consisting of 10 H atoms or 5 Si atoms
Sizes of Nanomaterials
105
沙子
宏粒子
花粉
微粒子
红细胞
104
细菌
Size
(nm)
1000
颜料
大分子
人类发丝
酵母菌
宠物毛屑
粘土
烟尘
100
病毒
10
小分子
致热原
硅胶
量子点
胶束
糖
1
气态离子
0.1
Substances
Examples of zero-dimensional nanostructures or
nanomaterials with their typical ranges of
dimensions
Various sizes of research subjects
核苷
Nucleotide DNA diam.
hemoglobin
生物
Biology
Cells
Nanoclusters 纳米团簇
Polymers Nanotubes
微制造
Micro-synthesis
g 射线
量子点
SETs
Quantum dots
晶体管
Transistors
e-beam lithography Photo-lithography
X射线
电磁波 g-ray
X-ray
Electromagnetic
waves
0.1
红血球
erythrocyte
Organellas
Biomolecules
合成
Synthesis
病毒
TM virus
核糖体
ribosome
紫外光
Ultraviolet
1.0
10
100
Nanometer（ｎｍ）
可见光
红外
Visible
Infrared
1,000
10,000
What is Nanotechnology?
Nanotechnology can be defined as being
concerned with materials and systems whose
structures and components exhibit novel and
significantly improved physical, chemical and
biological properties, phenomena and
processes due to their nanoscale size.
For example, new properties of nanomaterials
include low melting points or reduced lattice
parameters etc.
Classifications of Nanotechnology-1
According to the growth media,
Vapor phase growth includes laser reaction pyrolysis for
nanoparticle synthesis and atomic layer deposition (ALD) for
thin film deposition
Liquid phase growth includes colloidal processing for the
formation of nanoparticles and self-assembly of monolayers
Solid phase growth includes phase segregation to make
metallic particles in glass matrix and two-photon-induced
polymerization for the fabrication of three-dimensional
photonic crystals
Hybrid growth includes vapor-liquid-solid (VLS) growth of
nanowires
Classifications of Nanotechnology-2
According to the form of products,
Nanoparticles by means of colloidal processing, flame
combustion and phase segregation
Nanorods or nanowires by template-based electroplating,
solution-liquid-solid growth (SLS), and spontaneous
anisotropic growth
Thin films by molecular beam epitaxy (MBE) and atomic
layer deposition (ALD)
Nanostrucutred bulk materials including photonic bandgap
crystals by self-assembly of nanosized particles
Femme
Nanotechnology: BIG picture
Nanooptics
Nanomagnetism
fields contributing to
nanotechnology development
Nanotechnology
covers various research areas
Emergence of Nanotechnology-1
What’s not new?
The study of biological systems and the engineering of many materials
such as colloidal dispersions, metallic quantum dots, and catalysts have
been in the nanometer regime for centuries.
 Thousand years ago, Chinese used Au nanoparticles as an
inorganic dye to introduce red color into ceramic porcelains.
 In 1857, Faraday prepared Au colloids that was stable for almost
a centry before being destroyed during World War II.
Emergence of Nanotechnology-2
What’s new?
Our ability to image, engineer, and
manipulate systems in the nanometer scale
and understanding of atomic scale
interactions.
e.g. Discovery of STM, SPM, AFM techniques
Moore’s Law
Development of nanotechnology is driven at least partly by the
ever shrinking of devices in the semiconductor industry and
supported by the availability of characterization and manipulation
techniques in the nanometer level.
Dimensions of
transistors
halves every
18 months
50 nm
1M
Transistors per chip
1μm
1 st integrated circuit
Moore’s Law Trend Line
1 st transistor
Transistor Size
1 cm
1-5 nm
1950
1960
1970
1980
1990
2000
2010
2020
History of the integrated circuit
Number of transistors per chip
1958-1959: Integrated circuit invented by
– Jack Kilby (Texas Instruments)
– Robert Noyce (Fairchild Semiconductor)
1965: Gordon Moore (Intel)
– Observes that the density of transistors (computing
elements) has been doubling every two years
– Predicts this will continue or speed up
– Predicts 65,000 transistors per chip by 1975
The earliest transistor
The original contact
transistor made by Bardeen,
Brattain, and Shockley on
December 23 1947 at AT&T
Bell Lab.
[M. Riordan and L. Hoddeson,
Crystal Fire, W.W. Norton and
Company, New York, 1997.]
Au lead and nanocrystal connected by
bifunctional molecules
Field emission SEM image
(a) SEM image before the
nanocrystals are introduced. The
light region is ~10 nm thick. The
darker region is ~70 nm thick。
(b) Schematic cross-section of
nanocrystals bound via a
bifunctional linker molecule to the
leads.
[D.L. Klein, P.L. McEuen, J.E. Bowen
Katari, R. Roth, and A.P. Alivisatos,
Appl. Phys. Lett. 68, 2574 (1996).]
Fabrication Strategies
“自下而上”
Bottom-Up
“自上而下”
Top-Down
Simultaneous
synthesis
& assembly
Bottom up approach:
- Synthesis of building blocks
(nanoparticles, macromolecules, layers)
- Assembly of building blocks to nanostructures
Bottom Up（自下而上）vs. Top Down（自上而下）-1
“Bottom Up”
The approach refers to build a material up from the bottom: atom-by-atom,
molecule-by-molecule, or cluster-by-cluster.
— Polymers are synthesized by connecting individual monomers.
— In crystal growth, growth species such as atoms, ions, and
molecules imping onto the growth surface and assemble into
crystal structure.
It is effective to prepare nanostructures since most tools in a top-down
approach are too big to deal with tiny subjects.
Obtain nanostructures with less defects, more homogeneous chemical
compositions and better short and long range ordering.
— Bottom up approach is driven mainly by the reduction of
Gibbs free energy, leading to a state closer to a thermodynamic
equilibrium state.
Bottom Up（自下而上）vs. Top Down（自上而下）-2
Problems of“ Top-Down” approach: introduce internal stress,
surface defects and contaminations
— Nanowires made by lithography is not smooth on surface
and may contain a lot of impurities and structure defects.
— Such imperfections would have a significant impact on
physical properties and surface chemistry of nanostructures
and nanomaterials since the surface over volume in
nanostructures is very large.
The surface imperfection result in a reduced conductivity due
to inelastic surface scattering, which in turn would lead to the
generation of excessive heat.
Nanoprocessing
2 m
Figure 1.5. Miniature bulls were
fabricated by two-photon
polymerization. A titanium sapphire 蓝
宝石laser operating in mode-lock at
76 MHz and 780 nm with a 150femtosecond pulse width was used
as an exposure source. The laser
was focused by an objective lens of
high numerical aperture (~1.4). a–c,
Bull sculpture produced by raster
scanning; the process took 180 min.
d–f, The surface of the bull was
defined by two-photon absorption
(TPA; that is, surface-profile scanning)
and was then solidified internally by
illumination under a mercury lamp,
reducing the TPA-scanning time to 13
min. Scale bars, 2 m.
[K. Kawata, H.B. Sun, T. Tanaka, and
K. Takada, Nature 412, 697 (2001).]
The Thinker
Procedures of creation of CAD data
using a 3D scanner based on whitelight interferometer. The total number
of layers is 667 layers.
[Dong-Yol Yang, et al. Appl. Phys.
Lett. 90, 013113 (2007).]
“Molecular Person”
Ability of manipulating atoms
A molecular person consisting of
14 CO arranged on a metal surface
fabricated and imaged by scanning
tunneling microscopy (STM).
[P. Zeppenfeld & D.M. Eigler, New
Scientist 129, 20 (23 February 1991)
Richard Feynman’s prediction
There is plenty of room at the bottom
“But I am not afraid to consider the final question as to
whether, ultimately – in the great future – we can
arrange the atoms the way we want; the very atoms, all
the way down!” – Feynman, 1959
D.M. Eigler, E.K. Schweizer. Positioning single atoms with a scanning tunneling
microscope. Nature 344, 524-526 (1990).
Challenges in Nanotechnology
 The integration of nanostructures and nanomaterials
into or with macroscopic systems that can interface
with people.
 The building and demonstration of novel tools to study
at the nanometer level what is being manifested at the
macroscopic level. For example, new measurement
techniques are required to be extremely sensitive with
low noise.
 Doping in semiconductors has to be precisely controlled
at nanometer scale. Typical doping concentration
1018/cm3 corresponds to one dopant atom in a device of
10x10x10 nm3 in size. Concentration fluctuation and
location of dopants are critical at nanoscale.
Challenges in fabrication and processing
of nanomaterials and nanostructures
 Overcome the huge surface energy due to large
surface to volume ratio
 Ensure all nanomaterials with desired size, uniform
size distribution, morphology, crystallinity,
chemical composition, and microstructure that
altogether result in desired physical properties
 Prevent nanomaterials and nanostructures from
coarsening through Ostwald ripening or agglomeration
as time evolves.
References
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
Microscopy and Histology Catalog, Polysciences, Warrington, PA 1993-1994.
N. Itoh, in Functional Thin Films and Functional Materials: New Concepts and Technologies, ed., D.L. Shi, Tsinghua University Press and
Springer-Verlag Berlin, p.1, 2003.
National Nanotechnology Initiative 2000 Leading to the Next Industrial Revolution, A Report by the Interagency Working Group on
Nanoscience, Engineering and Technology (Washington DC: Committee on Technology, National Science and Technology Council)
http://www/nano.gov.
J. Ayers, in Ceramics of the World: From 4000 BC to the Present, eds. L. Camusso and S. Bortone, Abrams, New York, p.284, 1992.
H. Zhao and Y. Ning, Gold Bull. 33, 103 (2000).
J. Turkevich, Gold Bull. 18, 86 (1985).
M. Faraday, Phil. Trans. 147, 145 (1857).
J. Turkevich, Gold Bull. 18, 86 (1985).
B.E. Deal, Interface 6, 18 (1976).
M. Riordan and L. Hoddeson, Crystal Fire, W.W. Norton and Company, New York, 1997.
D.L. Klein, P.L. McEuen, J.E. Bowen Katari, R. Roth, and A.P. Alivisatos, Appl. Phys. Lett. 68, 2574 (1996).
M.A. Reed, C. Zhou, C.J. Muller, T.P. Burgin, and J.M. Tour, Science 278, 252 (1997).
R. F. Service, Science 293, 782 (2001).
J.H. Schön, H. Meng, and Z. Bao, Science 294, 2138 (2001).
J.D. Meindl, Q. Chen, and J.A. Davis, Science 293, 2044 (2001).
M. Lundstrom, Science 299, 210 (2003).
R.P. Feynman, J. Microelectromechanical Systems 1, 1 (1992).
C.A. Haberzettl, Nanotechnology 13, R9 (2002).
D.L. Feldheim and C.D. Keating, Chem. Soc. Rev. 27, 1 (1998).
F. Capasso, Science 235, 172 (1987).
W. Krastchmer, L.D. Lamb, K. Fostiropoulos, and D.R. Huffman, Nature 347, 354 (1990).
S. Iijima, Nature 354, 56 (1991).
C.T. Kresge, M.E. Leonowicz, W.J. Roth, J.C. Vartulli, and J.S. Beck, Nature 359, 710 (1992).
G. Binnig, H. Rohrer, C. Gerber, and E. Weibel, Phys. Rev. Lett. 49, 57 (1982).
G. Binnig, C.F. Quate, and Ch. Gerber, Phys. Rev. Lett. 56, 930 (1986).
T. Harper, Nanotechnology 14, 1 (2003).
B. Das, S. Subramanium, and M.R. Melloch, Semicond. Sci. Technol. 8, 1347 (1993).
C. Vieu, F. Carcenac, A. Pepin, Y. Chen, M. Mejias, L. Lebib, L. Manin Ferlazzo, L. Couraud, and H. Launois, Appl. Surf. Sci. 164, 111
(2000).
K. Kawata, H.B. Sun, T. Tanaka, and K. Takada, Nature 412, 697 (2001).
P. Zeppenfeld & D.M. Eigler, New Scientist 129, p.20 (February 23, 1991) and http://www.almaden.ibm.com/vis/stm/atomo.html.
Problems
1. What is the definition of nanotechnology?
2. Discuss the classification of nanomaterials based on the
form of products.
3. Discuss the fabrication methods of nanomaterials
according to the growth media.
4. What are the two major strategies to make nanomaterials?
Discuss their advantages and disadvantages.
5. What is Feynman’s prediction on nanotechnology?
Explain how do you understand it.