Rebirth 2002: Nano Life

Date: January 2, 2003.

Location: Beijing.

The Graduate School of the University of Science and Technology of China, referred to as the National University of Science and Technology, the School of Materials.

On the second day of New Year's Day, as usual, Ph.D. student Lu Qiang came to the laboratory early in the morning to start his experimental journey.

Walking into the research institute, the uncle of the security guard in the security room next to the door suddenly stopped him, "Student Lu Qiang, here is a letter from Professor Fu Weiqiang, please deal with it."

"Oh, okay." Lu Qiang replied.

Why should the letter sent to Professor Fu Weiqiang be handed over to Lu Qiang? Actually, there is a reason, because there are too many great private scientists in China. Just like the School of Mathematics, they often receive people claiming to have proved the "Goldbach Conjecture" Letters from folk mathematicians, the same is true of the Institute of Materials, there are often letters, and the content of the letters is very exciting, claiming that they have made a major discovery, what carbon becomes diamond, and a new material and new material has been invented.

Professor Fu Weiqiang, who had just returned to teaching in China, was interested in opening the envelopes at first, and after reading a few letters, he did not open the letters again, but handed them over to the students directly.

For Lu Qiang, this kind of letter is simply a preparation for his boring laboratory life. He also deeply remembers a letter he received last year. The content of the letter should be sent to the School of Chemical Engineering. I went there, but I don't know why it was sent to the School of Materials Science. The content involves a car that does not require external energy. It only needs to rely on the energy of bumps and frictions on the road to generate electricity. After storing this energy, it can walk forever. Later, the civilian scientist even called the college and said that the dean would be asked to go. Seeing him, otherwise delaying his major achievements and being responsible for it is really dumbfounding, but such ridiculous things happen every day.

It seems that today is no exception. I don't know what new invention is. Lu Qiang took the letter and saw that the mailing address on the envelope was written in a place he didn't know - Fengbai.

On the way, Lu Qiang opened the letter and read it. As he expected, another new substance was "invented". The person who wrote the letter said that he had successfully stripped graphene of a single-layer structure from graphite.

Lu Qiang knew the concept of graphene. His father was a university physics teacher and his mother was a university chemistry teacher. He had been nurtured since he was a child, and he developed a strong interest in physics early under the influence of his family, so what kind of physics books are there? Have a look.

Later, he became more interested in materials science. After completing his undergraduate studies at Yat Sen University, he was admitted to the Graduate School of the University of Science and Technology of China, and was lucky enough to become a domestic material science expert and a student of the well-known professor Fu Weiqiang.

Fu Weiqiang is a professor and doctoral supervisor at the School of Materials Science and Engineering, National University of Science and Technology. For many years, he has been engaged in the preparation method of nanomaterials, the microstructure and physical properties of nanomaterials. He also worked as a researcher at the Nano Center of Brookhaven National Laboratory in the United States. He returned to China in 1999 and worked as a doctoral supervisor in the School of Materials, National University of Science and Technology. His current research interests are high-temperature superconductivity and unusual topological phenomena in new carbon materials. He has published more than 100 papers in journals such as Nature and Science. The article has been cited about 7000 times by others.

Under the guidance of the mentor Wei Qiang, Lu Qiang is also full of interest in this field, and he is also actively trying to absorb all kinds of knowledge in this field.

For carbon, Lu Qiang understands better than most people, and is very fascinated by it. Carbon is a very common element in nature. It is widely distributed and exists in nature in various forms.

Life on Earth is based on carbon, the skeleton of life. To a certain extent, the professional basic course of materials science—organic chemistry is actually the chemistry of carbon. It has a long history of development, laying a solid foundation for the three major synthetic materials of plastics, rubber and fibers, helping human beings It has created a colorful world, which greatly facilitates the production and life of human beings; it has also laid a solid foundation for the synthesis of new drugs, and has become the protector of human health.

One of the biggest features of carbon is the existence of many allotropes, such as diamond and graphite that people are familiar with, carbene discovered in previous years, fullerenes and carbon nanotubes represented by C60.

Why is Lu Qiang so fascinated by carbon, because in his opinion, the properties of these materials composed of carbon can almost cover the properties of all substances on the earth and even the two opposite properties, such as from the hardest to the very soft, the whole Light absorption to full light transmission, insulator to semiconductor to conductor, adiabatic to good thermal conductivity, superconductor with high criticality, etc.

Why is carbon so magical? The answer lies in its unique electronic structure. Carbon is the sixth element, and its atoms have four valence electrons in the outermost layer. In addition to sp3 hybrid orbitals, C atoms can form single bonds. It can also form stable double and triple bonds with sp2 and sp hybrid orbitals, and can form flower covalent bonds with various atoms, thereby forming many substances with completely different structures and properties.

Graphite is one of them, and the graphene mentioned in the content of the letter is piled up layer by layer to form graphite. The essence of carbon nanotubes is a coiled graphene structure.

Walking into the laboratory, there was someone who came earlier than Lu Qiang. He was also a doctoral student brought by Fu Weiqiang. He was from Beijing, his full name was Liu Quanzhi, 31 years old. Although he was two years older than Lu Qiang, he was extremely funny.

When Liu Quanzhi saw Lu Qiang holding the envelope, he immediately smiled and said, "What new products have been invented this time?"

"Graphene!" Lu Qiang laughed.

"Come on, this invention is powerful, and it's about the same level as my elementary school. I could make graphene when I was in the first grade of elementary school. At that time, my little jj was as smooth as my head now." Liu Quanzhi was almost bald when he touched it. head, said helplessly.

In elementary school, everyone used pencils to write. Lu Qiang knew that a single layer of graphite sheets could be peeled off to form graphene with a very slight force when writing with a pencil.

"Hey, they are not elementary school level, he is talking about single-layer graphene!" Lu Qiang replied.

"It's amazing. It's also a single-layer graphene. Isn't that a two-dimensional material? Did you say any magic method? Blow it directly?" Liu Zhiquan laughed immediately after speaking.

Scientists have long believed that a single layer of graphene is not stable and can exist. Because the force of peeling graphene from graphite is enough to destroy the structure of graphene, and the melting point of solid is greatly reduced as the particle size decreases, when it is reduced to a few atomic layers thick, the solid will melt.

In addition, due to the existence of internal energy in two-dimensional crystals, the vibration amplitude of atoms is very large, so the dislocation of atoms will be quite serious, which will lead to the size of the distance between the atom and the atom that is not bonded to it and the size of the distance with it. The size of the distances between the bonded atoms is almost the same, so the monolayer structure cannot be maintained.

"It's a single layer of graphene that is glued with adhesive tape."

"What kind of tape is so awesome?"

"I didn't say, UU Reading www.uukanshu.com is estimated to be more sticky than 502! But this time the letter is quite confident, not only has the theory, but also sent the 'graphene' that he glued. Uh, where is it? Why didn't you see it? Huh?" Lu Qiang turned the opening of the envelope down, and saw a small piece of colorless transparent film with a side length of less than 2cm slipped from the envelope and slipped into Lu Qiang's palm. Lu Qiang couldn't even notice the slight reflection, and it was so light that it seemed weightless.

"Is this a plastic wrap?"

"What, bring it over and let me see it with a microscope." Liu Zhiquan said curiously.

"Are you all boring? When your instructor will know that your atomic force microscope looks at this thing, you will probably be scolded again." Lu Qiang rolled his eyes, although this atomic force microscope is not a relatively expensive instrument in the laboratory, but the guidance Master Wei Qiang has always emphasized that the use of any instrument needs to be cautious, but Liu Zhiquan has a rather jumpy personality, but such a personality can always stay in the laboratory, which shows his spirituality and ability to some extent.

"Isn't this a bottleneck in my research direction? I have to find something to be happy about."

"I really like you, take it."

Ten minutes later, Liu Zhiquan suddenly shouted, "I'm so stupid."

Lu Qiang, who had already done the experiment, was so frightened that he almost made a mistake.

At this time, Fu Weiqiang also walked into the laboratory, just when he heard Liu Zhiquan shout, he frowned and said solemnly, "Liu Zhiquan, how many times have I told you, try to keep quiet in the laboratory, don't make any noise. "

Although he was scolded by Fu Weiqiang, Liu Zhiquan didn't care at this moment. He danced and excitedly said to his mentor, "Professor, look at it, it's really a single-layer graphene!"