Research status and development prospects of the h

Research status and development prospects of nano materials

research status and development prospects of nano materials

January 12, 2005

many people may have heard of the word "nano", but what is nano and what is nano materials may not be clear to many people. This paper mainly introduces the research status and development prospects of nano and nano materials. I believe that with the development of science and technology, More and more nano materials will come into people's lives and benefit mankind

nano is the transliteration of English nano meter, which is a physical unit of measurement. 1 nano is 1 billionth of 1 meter; Equivalent to the length of 45 atoms arranged. Generally speaking, it is equivalent to one tenth of the thickness of hair

like millimeter and micrometer, nanometer is a concept of scale and has no physical connotation. When the material reaches the nanometer scale, about 1-100 nm, the performance of the material will suddenly change, and special properties will appear. This kind of material is composed of special properties that are different from the atoms and molecules originally composed, and also different from macroscopic substances, that is, nano materials. If it is only a material with nano scale and no special properties, it cannot be called nano material. In the past, people only paid attention to atoms, molecules or cosmic space, and often ignored this intermediate field, which actually exists in nature, but they didn't realize the performance of this scale range before. Japanese scientists were the first to truly recognize its performance and quote the concept of nano. In the 1970s, they prepared ultra-fine ions by evaporation. Through studying its performance, they found that after a conductive and heat-conducting copper and silver conductor was made into a nano scale, it lost its original properties and showed neither conductivity nor heat conduction. The same is true of magnetic materials, such as iron cobalt alloy. If it is made into a size of about 20-30 nm, the magnetic domain becomes a single magnetic domain, and its magnetism is 1000 times higher than the original. In the mid-1980s, people officially named this kind of material nano materials

in the vibrant 21st century, the rapid development of information, biotechnology, energy, environment, advanced manufacturing technology and national defense will inevitably put forward new requirements for materials. The size requirements of materials for miniaturization, intelligence, high integration, high-density storage and ultrafast transmission of components are becoming smaller and smaller; Aerospace, new military equipment and advanced manufacturing technology require higher and higher material properties. Innovation of new materials and new technologies induced on this basis. The innovation of new products is the most influential strategic research field for social development, economic revitalization and national strength enhancement in the next 10 years, and nano materials will be one of the key materials that play an important role. Nano materials and nanostructures are the most dynamic research objects in the field of new materials and have a very important impact on the future economic and social development. They are also the most active and closest to the application of nanotechnology. In recent years, nano materials and nanostructures have made remarkable achievements. For example, the advent of quantum disks with magnetic nanorod arrays with a storage density of 400g per square centimeter, high-efficiency nano array lasers with low cost and adjustable light-emitting frequency band, nanostructured solar cells and thermoelectric conversion elements with low price and high energy conversion, and ablation resistant, high-strength and high toughness nanocomposites used as railgun tracks, It fully shows its great potential in the application of new pillar industries and high-tech fields of the national economy. As American scientists estimated, "this extremely small material invisible to the naked eye is likely to bring a revolution to all fields". The application of nano materials and nanostructures will provide new opportunities for how to adjust the layout of pillar industries of the national economy, design new products, form new industries and transform traditional industries into high-tech content

the important scientific significance of studying nano materials and nanostructures is that it opens up a new level of people's understanding of nature and is the source of knowledge innovation. Because the scale of nanostructure unit (1 ~ 100urn) is equivalent to many characteristic lengths in matter, such as the de Broglie wavelength of electrons, the superconducting coherence length, the thickness of tunneling barrier, and the critical size of ferromagnetism, the physical and chemical properties of nano materials and nanostructures are not only different from microscopic atoms and molecules, but also different from macroscopic objects, which makes people explore nature The ability to create knowledge extends to the intermediate field between macro and micro objects. Finding new phenomena, understanding new laws, putting forward new concepts and establishing new theories in the field of nano materials will lay the foundation for building a new framework for the scientific system of nano materials, and will also greatly enrich the research connotation of new fields such as nano physics and nano chemistry. At the turn of the century, high toughness nano ceramics and super strong nano metals are still important research topics in the field of nano materials; Nanostructure design, the combination of heterogeneous, heterogeneous and nano elements with different properties (zero dimensional nanoparticles, one-dimensional nanotubes, nanorods and nanowires). The surface modification of nano scale elements has become a new hotspot in the research of nano materials. People can have more degrees of freedom to synthesize new materials with special properties according to their own wishes. The use of new physical properties, new principles and new methods to design nanostructure principle devices and the modification of traditional nanocomposites are pregnant with new breakthroughs

1 Research shape and trend

nanotechnology produced in the preparation and application of nano materials is likely to become the leading technology in the first 20 years of the next century, driving the development of the nano industry. At the turn of the century, the world's advanced countries have rearranged the research of nano materials from the perspective of future development strategy. It is very important to meet new challenges at the critical moment of the turn of the millennium, pay close attention to the project establishment of nano materials and nano structures, and quickly organize scientific and technological personnel to carry out research around the national goals

the achievements made by the birth state of nano materials over the years and its influence and penetration in various fields have been remarkable. In the 1990s, the connotation of nano material research has been expanding and the field has been gradually broadened. A prominent feature is that basic research and applied research are closely connected. The transformation speed of laboratory results is faster than people expected. Both basic research and applied research have made important progress. Nano Cu material with 50urn grain size has been successfully prepared in the United States, and its hardness is 5 times higher than that of coarse-grained Cu; The yield stress of PD with 7urn grain is 5 times higher than that of coarse-grained PD; The plasticization of intermetallics with high strength has always attracted people's attention, and the nanocrystallization of grains has brought hope to solve this problem.

according to the development trend of nano materials and its important position in the development of high technology in the century, the governments of developed countries in the world are deploying the original 10-15 year research plan on nanotechnology. In 1998, the national foundation of the United States (NSF) invited bids from the national scientific and technological community for the synthesis, processing and application of nano functional materials as an important basic research project; Several programs of DARPA (national advanced technology research department) in the United States also take nanotechnology as an important research object; In recent years, Japan has formulated various plans for the research of nanotechnology, such as the basic principles of ogala plan, ERATO plan and quantum functional devices, as well as the fire performance requirements of thermal insulation materials and the fire resistance of system structure, which are important conditions for determining the fire safety performance of external thermal insulation system. In 1997, nanotechnology invested 128million US dollars; The German Ministry of scientific research and technology helped the federal government formulate a 15 year plan for the development of nanotechnology from 1995 to 2010; The British government has invested heavily in nanotechnology research; In 1997, Western Europe invested 120million US dollars. According to the latest report of nature on July 8th, 1999, the application potential of nano materials has attracted the attention of the White House; U.S. President Bill Clinton personally asked about the research of nano materials and nanotechnology, and decided to increase investment. The funding support will increase from US $250million to US $500million in the next three years. This shows that the research boom of nano materials and nanostructures will continue to develop for a long time in the next century

2 international trends and development strategies

on July 8, 1999, nature (volume 400) released an important news entitled "the U.S. government plans to increase investment to support the rise of nanotechnology". In this article, it is reported that the US government has doubled its investment in nanotechnology research within three years, from US $250million to US $500million. President Clinton will submit a bill supporting nanotechnology research to Congress for approval next February. In order to accelerate the research of nano materials and technologies in the United States, the White House took temporary emergency measures to increase the original funding intensity of 197million US dollars to 250million US dollars. On August 19, BusinessWeek said that the U.S. government decided to list nanotechnology research as one of the 11 key areas in the first 10 years of the 21st century. BusinessWeek included Nanotechnology (the other two are life science and biotechnology, which obtain energy from outer planets) among the three areas that may make important breakthroughs in the 21st century. There are two reasons why the White House of the United States suddenly attaches so much importance to nano materials and technology at the critical moment of the end of the 20th century: first, the German Ministry of science and technology made a prediction on the market of nano technology in 2010, which is estimated to reach $1440 billion. The United States is trying to occupy a considerable share in such an attractive market. Williams, the head of basic research in the United States, said that the original application of nanotechnology is far beyond the computer industry. The White House Office of strategic planning also believes that nano materials are the most important part of nanotechnology. In the report of nature, it is also mentioned that the United States has led the world in the nanostructure assembly system and the preparation and synthesis of high specific surface nanoparticles. In the design and modification of nano functional coatings and the application of nano materials in biotechnology, the United States is tied with the European Community for the first place in the world. Components and Nanosolids with higher strength and higher meter size should also compete with Japan. In July, 1999, the University of California, Los Angeles and Hewlett Packard successfully developed 100urn chip. The University of Minnesota and Princeton University successfully prepared quantum disk in 1998. This disk is a nano array system composed of magnetic nanorods, and the density of 10bit/s has reached 109bit/s. American businesses have organized relevant personnel to convert the current sound speed quickly but with buzzing, The market is expected to be 40billion US dollars in 2005. In 1988, the French first discovered the giant magnetoresistance effect. By 1997, nanostructured devices based on the principle of giant magnetoresistance have been introduced in the United States, which will have important application prospects in magnetic storage, magnetic memory and computer read-write heads

recently, the research department of Kodak company in the United States successfully studied a new nano powder with the functions of both pigment and molecular dye, which is expected to bring revolutionary changes to color printing rubber. Nano powder materials are likely to inject new high-tech content into traditional industries and products in the modification of rubber, pigments and ceramic products, and occupy an important share in the future market. The application research of nano materials in medicine has also attracted attention. It is these studies that make the White House realize that nano materials and technology will occupy an important strategic position. The second reason is that the field of nano materials and technology is the source of knowledge innovation and technological innovation, the discovery of new laws, new principles and the construction of new theories