Fullerene is a general term for a class of spherical or elliptical all-carbon cage molecules. It is another carbon allotrope discovered after diamond, graphite and amorphous carbon. Among them, C60 with 60 carbon atoms is the most fully studied and most representative. The C60 was officially discovered in 1985, and since then it has started its wonderful life. Now, please follow me, approach C60 and its family, and feel their legend.
1 Innate aristocratic temperament
On this blue planet we live on, one of the unresolved questions that affects human beings is probably where we come from. If Darwin's theory of evolution has solved the problem to some extent, the origin of life may be more thorny and fascinating when viewed from a broader perspective. Since our planet is just an ordinary member of the vast sea of stars, and the time of human existence is too short compared with the life memory of the earth, scientists realized that this question may be difficult to answer if it is limited to this , So, the line of sight began to turn to the vast universe. Astrophysicists have long found evidence of carbon clusters in the atmospheres and comet tails of carbon-rich stars. This discovery is exciting for a simple reason: Since carbon is the main element of living organisms on Earth, could the presence of carbon atoms in the universe provide a key clue to the origin of life?
It is against this background that fullerenes come into play. In 1947, Hahm et al. The presence of carbon atom clusters with an atomic number less than 15 was confirmed by mass spectrometry; around 1965, the Oak Forest National Laboratory in the United States discovered a shiny black substance with a chemical formula similar to it; in 1984, et al. Generating carbon clusters from solid graphite using laser vaporization/helium pulse expansion and detecting the presence of clusters using UV laser ionization combined with time-of-flight mass spectrometry; British chemists and research groups have been studying interstellar space in the 1970s, As a result, when analyzing carbon-rich interstellar dust, they unexpectedly discovered a class of molecules composed only of carbon, hydrogen, and nitrogen. They have studied it intensively, but still haven't found a suitable atom clustering technique. In 1984, he came to the United States from England to meet Curl and, at his suggestion, toured the lab. At the time, he was leading a research group studying the properties of atomic beams. After watching an experiment in which silicon carbide was vaporized by a laser in a flow of helium, it occurred to me that this technique could be applied to the study of carbon atoms. In 1985, they cooperated with He and successfully detected C60 by increasing the partial pressure of He, prolonging the clustering time, and optimizing the experimental conditions[1].
The universe, the origin of life, and the two aspects that most affect human nerves are involved. The nobility of fullerenes is natural.
2 The perfection of form, the paragon of art
Many times, you will find that the uncanny workmanship of nature coincides with human concepts. Or in front of nature, human beings may be just primary school students in many cases without knowing it. When the C60 was discovered, its mystery had not been lifted. Inspired by architect Fuller's circular dome design, they felt that C60 should be a hollow cage structure. It turns out this is true. Fuller himself may not have imagined that in the future, a molecule in the nanoworld would crash into his proud building, but he must have been encouraged by nature to choose the same design at different scales. What's also interesting is that the structure of the C60 perfectly crashed the football, so it was nicknamed ""[2]. A person can win such attention not by strength but by appearance. No wonder in 1991 the world's authoritative magazine named him a star molecule.
Just as the fame of a star will always bring countless imitators and fans, the emergence of C60 has also set off an upsurge in the research of carbon nanomaterials. People are sensitively aware that this ubiquitous element, which has been used for thousands of years, can burst into new and greater life. Other members of the fullerene family were soon discovered. But no matter how the number of atoms changes, the number of five-membered rings in the molecule remains unchanged and cannot be changed. Just like a huge human family, no matter how they are spread out, there is always a surname as a link to link everyone together. Not only that, carbon nanotubes and graphene, close relatives of fullerenes, have also been discovered one after another. The position of the carbon family in natural science has never been as prominent as it is today, and fullerenes are indispensable.
3 Yangchun Baixue VS Lower Riba People
At the beginning of the birth of C60, due to the lack of macro preparation technology, ordinary researchers basically said that "a happy life depends on thinking". In 1990, Krä et al. Plasma arc gasification of graphite rods , invented a method for preparing C60 in macroscopic quantities [3]. During the experiment, the discharge chamber was evacuated first, and then an inert gas protection was introduced. When the high-purity graphite electrode is close to the graphite electrode for arc discharge, a large amount of granular soot generated by the evaporation of the graphite electrode is deposited on the inner wall of the water-cooled reactor under the action of the airflow, and then the soot can be collected. The method has the advantages of high yield, simple equipment, safety and reliability, and low cost. However, at this time the price of the C60 is still surprisingly high. In 1995, the United States completed the research and development of the 10-gram C60 preparation process; in 2005, Japan built the first ton-level C60 production line. Thanks to the unremitting efforts of people in the industry, the price per gram of C60 has dropped from the initial tens of thousands of yuan to several hundred yuan, and C60 has finally completed the transformation from Yangchun Baixue to Xialipa people.
Completion of macro-processing methods has enabled extensive research on C60. Since then, related research work has advanced by leaps and bounds, and the secrets contained in C60 have been revealed one by one. From superconductors, to organic solar cells, to artificial photosynthesis, C60 has discovered many frontiers of science and technology, and each discovery is exciting. In cosmetics, the excellent free radical scavenging ability of C60 makes it a potential antioxidant additive [4]; at the same time, it inhibits AIDS protease, light-induced DNA shearing, gene transfection, anti-tumor, anti-neurodegenerative diseases and other activities. The discovery of C60 opened the door for the application of C60 in biomedicine. The rich physical and chemical properties and biological activity of C60 brought it great honor, and its discoverers finally won the 1996 Nobel Prize in Chemistry.
4 Take root in China and forge ahead
The so-called economic base determines the superstructure, and scientific research, as a branch of national economic and social development, can best reflect the comprehensive strength of a country to a certain extent. China has a glorious history of 5,000 years, but suffered huge losses in modern times. The short-sightedness of the ruling class has led to the poverty and weakness of the country, and almost all the engines of modern science have nothing to do with China. This situation has not completely changed until today. The period when the C60 appeared was just catching up with my country's reopening of the country, and a hundred flowers bloomed. In this emerging research field, we have made a series of gratifying progress. The flower of fullerene research and industry has been deeply rooted in the land of China. But we must see that compared with the European and American powers, we still have a big gap. Generally, fullerene molecules contain multiple carbon-carbon double bonds, which have stronger antioxidant capacity than vitamin C and carotene, and can be used as cosmetic additives. Fullerene cosmetics have been studied for many years. Since L'Oreal announced its first patent in 1994, fullerene cosmetics have achieved rapid development worldwide [5], especially in Japan, which has a relatively good degree of industrialization. In China, the industrial chain is relatively lagging behind. The first fullerene raw material plant was established in 2012 with limited capacity. Affected by this, there is still a certain gap between fullerene cosmetics and foreign countries. At present, there are two main forms of water-soluble fullerene cosmetic raw materials on the market: physically coated viscous stock solution and chemically modified dry powder. The former has many inconveniences in transportation and storage, and the long-term stability of fullerenes is difficult to guarantee; while the latter has not yet been included in the catalog of cosmetic raw materials in my country [6]. Therefore, the development of new fullerene cosmetic raw materials is an urgent task, and it is of great significance to promote the development of my country's fullerene cosmetic industry.
At present, the state is encouraging and advocating scientific and technological innovation with unprecedented efforts. The development of fullerenes also ushered in the spring. In August 2018, the 3rd International Symposium on Fullerene Science was held in Tonghua, Jilin. Scientists from all walks of life gathered together to discuss the development of fullerenes. During the meeting, the China Fullerene Application Industry Innovation Alliance was established, which greatly promoted the scientific research and application development of fullerene. Time waits for no one, and we who love fullerenes have no reason not to be full of energy and forge ahead. As a member of the domestic fullerene research team, the fullerene R&D team has long been committed to the basic research of fullerene. Since 2004, he has undertaken four National Natural Science Foundation of China projects in the fields of physical chemistry and material chemistry. Several research papers have been published in mainstream journals. In recent years, in response to the inherent needs of the scientific development of fullerenes, Shandong University has established a school-level cosmetics technology research center. Through doping and chemical modification, combined with different purification processes, a variety of fullerene high-efficiency anti-aging additives have been obtained; at the same time, in close cooperation with industry insiders, we strive to broaden the types of fullerene in the cosmetic raw material catalog.
Figure 1 Development history of fullerenes
5 Conclusion
The ancients said: The road is long and long, and I will search up and down. The so-called "the sea of learning is boundless, the boat crosses by itself, the good times are ahead, hurry up". We believe that where the heart is, the dream is there. The joint efforts of Fuller people will surely win a bright future!
refer to:
[1], Hardware; , J.; Oh, SC; Curl, Radio Frequency; , RE 1985,318, 162.
[2] Jim Bagot. Perfect symmetry—the serendipitous discovery of fullerenes. Li Tao, Cao Zhiliang, translated. Shanghai: Shanghai Science and Technology Education Press, 1999.
[3] Carat, W.; Lamb, LD; , K.; , Ph.D. 1990, 347, 354.
[4], PJ; , E.; , Public Number; , Young; , KF, 254, 1183.
[5] MD, SZM;, S.; , Hello: ,13, 1071.
[6] Circular of the State Food and Drug Administration on Publishing the List of Names of Raw Materials Used in Cosmetics (2015 Edition) (2015 No. 105). List of names of used cosmetic raw materials. (2015-12-23) [2019-08-03].
This article has been accepted by the journal "University Chemistry"
doi: 10.3866/Peking University.