Why did graphene become a scam in China?
However, although the application prospects of graphene are getting more and more promising, another completely different statement is also categorical: Graphene is a scam in China.
In March 2015, the Chongqing Institute of Green and Intelligent Technology of the Chinese Academy of Sciences announced the launch of a graphene mobile phone called "GALAX SETTLERα". According to the publicity at the time, its light transmittance was as high as 97%, the charging rate of the mobile phone was increased by 40%, and the battery life Extending by 50%, the energy density of the battery also increases by 10%. Because it is tied to graphene, although this phone is only equivalent to a thousand-yuan configuration, the price can be as high as 2,499 yuan.
Eight months later, despite the announcement of the first batch of 30,000 units of this graphene phone, it has not been sold in the market.
But people can buy a variety of other graphene products. For example, Shengquan Group, a listed company on the New OTC Market, has launched graphene socks and underwear on the market. According to the company’s publicity, they added biomass graphene "inner warming" fiber to the product, which is a brand-new intelligent multifunctional composite fiber that "has the ability to activate immune cells, protect against ultraviolet rays, improve microcirculation, antibacterial and antibacterial , Heat-increasing and sun-increasing properties, and it can also deodorize."
According to the company’s publicity, they carbonized plant stalks to extract graphene, using the superconductivity of graphene as a raw material for the production of clothes. They also plan to launch a smart bra that measures subtle changes in women’s chest temperature through a built-in sensor to effectively prevent tumors and breast cancer. They also plan to apply them to military uniforms. At present, these so-called graphene products are expensive, the price of a pair of socks. For more than 50 yuan, the price of a pair of underwear is close to 300 yuan, the price of a graphene belt is close to 600 yuan, and the heat-generating clothing is sold for more than 1700 yuan.
"In the past few years, when nanomaterials were hyped, there was a lot of hype about the concept of'nano+' in China. This time, the concept of'graphene' is the same. Many graphene products are a scam." National 863 project leader, materials scientist, Said Qi Lu, a professor at the School of Chemistry and Molecular Engineering of Peking University. Due to its contribution to new materials and energy, Qilu is also known as the main founder of my country's lithium cobalt oxide and lithium manganate battery cathode materials.
According to the reporter's understanding, graphene is currently divided into two types: monoatomic thin film graphene and graphene powder. The preparation of the former mainly uses carbon-containing gases such as methane and acetylene as raw materials and is synthesized by chemical vapor deposition, which has nothing to do with graphite or straw.
Graphene powder is obtained from natural graphite, oxidized by concentrated acid and strong oxidizing agent, and then reduced by expansion heat treatment. As for graphene extracted from straw, it is said that 15 catties of corncob can extract one catty of graphene. Many people in the industry seem to be unheard of.
Apart from the obvious scam graphene panties, the "graphene batteries" and "graphene lithium batteries" that many research institutes and companies are keen to develop are also accused of lying.
At present, the practice of graphene application in the battery field is generally to add graphene materials to the positive and negative electrodes of lithium batteries. "This approach is obviously misleading." Recently, Tsinghua Energy Internet researcher Liu Guanwei questioned the "graphene battery" article on the Internet.
In this article titled "The Legendary "Graphene Battery" technology, is it a big lie? "In the article, Liu Guanwei gave a clear view from the beginning:
The technology of "graphene battery" is close to non-existent. Graphene can only increase the charge and discharge rate in theory, but it does not help to increase the capacity (energy). People who are going to be disappointed), the meaning of the gimmick is far greater than the practical value.
According to Liu Guanwei, according to the classic electrochemical nomenclature, the lithium-ion batteries used in general smartphones should be named "lithium cobalt oxide-graphite batteries." It is called a "lithium ion battery" because lithium ion plays a major role in it. "Strictly speaking, graphene only plays an auxiliary role in the battery, so a battery using graphene cannot be directly called a'graphene battery'."
In Liu Guanwei's view, only graphene is used as a "conductive additive" in lithium batteries that has basically entered the market now. But even the application of "additives" has been questioned.
Graphene can be used as a conductive agent to promote the fast charging and discharging of lithium batteries. In theory, it can improve the rate performance. However, if the dispersion process is not in place and the mixing is uneven, everything is a castle in the sky. In addition, there are many high-quality and inexpensive materials. The expensive graphene must be used. "
The reporter noticed that Liu Guanwei's views were recognized by many senior experts in the industry, including Zhang Yuanbo, Qilu, Professor Lu Hongbin of the Department of Polymer Science of Fudan University, and Professor Yuan Guohui of the Department of Applied Chemistry of the School of Chemical Engineering of Harbin Institute of Technology.
"Who can come up with the data up to now? Has anyone made such a battery?" Qilu also believes that "the positive and negative electrodes of lithium batteries are both layered structures, so under certain external conditions, It forms a migration from the positive electrode to the negative electrode. Graphene is a single-layered carbon atom ring structure, which is determined by its own chemical and physical properties and will not form a separate negative electrode material for lithium batteries."
Many people are wasting their lives for this?
Regarding the doubts of industry experts, as the secretary-general of the "China Graphene Industry Technology Innovation Strategic Alliance", Li Yichun said: "Although the industry is controversial, scientific and technological innovation, anything can happen. Some experts believe that it is impossible. It's all achieved, and some experts are too arbitrary, but we must have an open mind."
Up to now, it is impossible to know the true face of Qingdao’s newly developed "world-leading graphene lithium battery". Huawei’s response is "there is research on graphene, but it will not be commercialized so quickly." As the Shanghai Institute of Ceramics, Chinese Academy of Sciences The leader of the "Graphene Super Electric Vehicle Battery" team, Huang Fuqiang's defense is that "everyone will draw different conclusions from different angles, but the essence is the same."
In fact, even Andre Gaim, who won the Nobel Prize in 2010 for his discovery of graphene, can't understand the current frenzied graphene in China. At the end of October 2015, when Gaim attended a graphene product exhibition held in Qingdao, he disregarded the host’s face and made it clear that “many application products including graphene batteries may be suspected of hype at present.”
On the day Gaim attended the meeting, the "2015 Global Graphene Industry Research Report" first published by the China Graphene Industry Technology Innovation Strategic Alliance was also released, which showed that China not only ranked first in the world in the number of papers published on graphene at the end of 2012 , And the number of patents has risen rapidly in the past three years.
However, Gaim also pointed out in an interview with Chinese media that half of the research on many published graphene papers will be discarded. On the other hand, many patents, especially those produced by universities, 90% of which have no value, 99% of patents will eventually become invalid, and maintenance of these patents will also cost a lot of money, and many people are wasting their lives for this.
"Although China ranks first in the world in terms of the number of graphene papers published, many scientific research institutes do not know what the industry wants, and the problem of disconnection between scientific research and application is prominent." Kang Feiyu, Dean of Tsinghua University Shenzhen Graduate School and carbon material expert Publicly stated.
These doubts do not stop the pace of Chinese graphene practitioners. On January 16, Changzhou West Taihu Science and Technology Industrial Park held a signing ceremony for graphene projects, and 21 graphene projects collectively settled in Changzhou. Liu Zhifeng, secretary of the Party Working Committee of Changzhou West Taihu Science and Technology Industrial Park, said that Changzhou's graphene industry is moving towards the goal of "creating a tens of billions of specialty industries."
There are many graphene industrial parks like Changzhou in China. According to the reporter's understanding, large-scale graphene industrial parks have been formed in Chongqing, Wuxi, Qingdao, Tangshan and other places. And more graphene industrial parks are expected to blossom in 2016.
In Changzhou, an insider of 2D Carbon Technology Co., Ltd. told reporters that they were established in Changzhou in 2011 and have grown to a scale of 200 people. In 2012, they produced the world's first capacitive graphene touch screen. In the past two years, they have also used the high heat radiation efficiency of graphene films to develop some heatable clothing. Their research and development directions also include graphene composite materials, solar cells, and wearable sensors. However, he admitted that these products actually have little to do with graphene.
It is the capital market that tastes the sweetness earlier than industrial parks, scientific research institutes, universities, and enterprises. Relevant data shows that a total of 60 listed companies in Shanghai and Shenzhen have their graphene business. In mid-August 2015, Del Home Furnishings, located in Jiangsu, announced its investment in graphene super lithium batteries and other projects. After drawing up the blueprint of "increasing annual revenue by 2.8 billion yuan and annual net profit by 450 million yuan", this company caught up with " The share price of a company with the concept of "graphene battery" seems to have been on a rocket, with an increase of 158.4% in more than two months.
The road to industrial commercialization is long
"In the domestic application of graphene, there are actually not many companies that actually do graphene. Many of them are companies that used to do carbon materials such as graphite, or even completely unrelated companies that use the banner of graphene, or speculate in stocks, or fight for it. National Funds, there are almost no companies that really make graphene and can really make money." said Zhu Hongwei, a professor at the Micro-Nano Mechanics Center of the School of Materials Science and Engineering, Tsinghua University.
In Liu Guanwei's view, not only are many domestic graphene scams, but also a lot of hype about foreign projects. In his article questioning graphene batteries, Liu Guanwei stated that "the Spanish Graphenano company with graphene batteries" could not find any valid information whether it was the three German auto companies that claimed to cooperate or on the website of the Patent Office.
So, why is the highly anticipated "king of new materials" in such an awkward controversy?
According to the reporter's understanding, there are three reasons: On the one hand, no matter whether domestic or foreign, there is no technically found industrial synthesis method to obtain large-area single crystal graphene. On the other hand, the downstream industry chain of graphene has not yet formed in the market. The biggest demand for graphene is only the major scientific research institutes and laboratories, and no large amount of graphene has been put into industrial operation.
As early as 2010, researchers from Sungkyunkwan University in South Korea and Samsung Corporation produced a transparent and flexible display screen composed of multilayer graphene and a polyester sheet substrate. At that time, Hong Bingxi, a professor at Sungkyunkwan University and the corresponding author of the paper, proposed that their method could be used to manufacture graphene-based solar cells, touch sensors, and flat-panel displays. But he also admitted at the time that it was too early for large-scale manufacturing and commercialization-five years later, Hong Bingxi's method still remained in the laboratories of Samsung and Sungkyunkwan University in South Korea.
The last aspect is the cost of graphene preparation. Due to the inability to mass produce, the cost of graphene preparation has remained high, and the high cost has also hindered the pace of industrialization in the downstream market. Previously, the price of graphene was as high as 5,000 yuan/gram, which was several times more expensive than gold. "The bottle of something that is not surprising is more expensive than gold. A few grams of graphene powder is worth hundreds of thousands of yuan. When we fly on the plane, we are transported by several people for fear of being confiscated by the security check." The startups studied used to describe it this way.
In Canada, Grafoid and the National University of Singapore established the world’s largest graphene research center (NUS), and launched a new production base in Ontario in 2014. This 20,000-square-meter base mainly produces graphene powder. At that time, The person in charge of the company said that they can mass-produce high-quality graphene at a low price. However, more than a year later, there has not been any new news from this base.
Therefore, it is mainly technical issues that really hinder the large-scale application of graphene. Among them, the development of consistent and reproducible synthetic methods for low-cost, large-scale, and high-quality graphene is the biggest difficulty.
An interesting thing that people are familiar with is that Andre Gaim used scotch tape to get graphene. But what people don't know is that the graphene obtained by this method has a small size, generally between 10 microns and 100 microns, and has the disadvantages of low yield and high cost, and cannot meet the requirements of industrialization and large-scale production.
Later, the graphite oxide reduction method is one of the most commonly used methods for preparing graphene. However, this method mainly obtains graphene powder, which has many defects and poor electrical and mechanical properties. Concentrated sulfuric acid is needed to oxidize graphite, which is a difficult problem in industrial waste liquid treatment.
Since then, people thought that it is not necessary to use graphite to prepare graphene, but only needs to try to make carbon atoms form a thin film. Chemical vapor deposition (CVD) came into being. This method introduces gases such as ethylene or acetylene into a reaction chamber to decompose these gases at high temperature. After cooling, carbon atoms are deposited on the surface of the substrate to form graphene. . Although CVD can meet the requirements for large-scale and high-quality graphene production on a large scale, the problem is that due to its high cost and complex process, the application of this method in graphene production is limited.
Due to the huge difference in preparation methods, the price of graphene powder and CVD film also differs by thousands of times. For example, 1 gram of graphene powder only costs less than 10 yuan, while 1 square meter of graphene film costs tens to hundreds of yuan, and its weight is actually less than 1 mg.
There is another main method-solvent stripping method. Since the entire liquid phase exfoliation process does not introduce any defects on the surface of graphene, it provides broad application prospects for its applications in the fields of microelectronics, multifunctional composite materials, etc. The disadvantage is also that the yield is very low.
Therefore, from an application point of view, graphene is currently in the storytelling stage at home and abroad. "In addition, the current industrial standards for the size, uniformity and reliability of graphene in consumer electronics have not yet been determined, so the actual use of graphene in consumer electronics has not yet been shown." Zhu Hongwei believes that graphite At present, ene can make small-scale devices in the laboratory, but mass production and integration quality cannot be guaranteed. "At least there is no hope yet."
In fact, even Gaim himself has reservations about the current commercialization of graphene. Gaim believes that graphene is a primer that has driven the development of a wider range of two-dimensional materials. But for graphene, from the perspective of physics, it has reached a bottleneck, and unless there is a greater breakthrough in the future, it is difficult to make further improvements.
Memorabilia of Graphene Development
2004: Andrei Geim and Konstantin Novoselov obtained graphene by a simple mechanical stripping method of tape. The two won the Nobel Prize in Physics in 2010.
December 2009: Japan's Fujitsu Research Institute announced its successful use of graphene to make transistors.
February 2010: IBM developed Graphene FET (Field Effect Transistor).
June 2010: Samsung and Professor Sumio Iijima of Sungkyunkwan University in South Korea used graphene to make flexible transparent electrodes.
January 2012: Jiangnan Graphene Research Institute, 2D Carbon and other companies announced that they have jointly developed the world's first graphene capacitive touch screen for mobile phones.
August 2012: Nokia disclosed that its R&D department is working on graphene photoelectric sensors.
September 2012: Sony announced that it has developed a roll-to-roll process to manufacture graphene.
January 2013: Chongqing Research of Chinese Academy of Sciences
The institute announced that it has developed the first 15-inch single-layer graphene in China.
May 2013: Jiangsu Changzhou 2D Carbon Technology Co., Ltd. said that the world's largest graphene transparent conductive film production line was officially put into operation, with an annual production capacity of 30,000 square meters.
November 2013: Changzhou Sixth Element Material Technology Co., Ltd. started production of 100 tons of graphene oxide and graphene powder production lines.
April 2014: Samsung announced that it has developed a technology to form single crystal graphene on semiconductor wafers.
July 2014: IBM announced that it would invest US$3 billion in graphene development in the next five years.
2015: "Made in China 2025" was officially promulgated by the State Council, once again putting graphene on the agenda as a new energy source.
Related Links: The Past and Present of the King of New Materials
Carbon is one of the most important elements. It has unique properties and is the foundation of all life on earth. Pure carbon can be hard diamond or soft graphite.
Because this material is made from graphite and contains the basic feature of olefins-the double bond between carbon atoms, it is called graphene. In fact, graphene exists in nature, but it is difficult to peel off a single-layer structure. Layers of graphene are stacked to form graphite, and 1 mm thick graphite contains about 3 million layers of graphene. The adhesion between the layers is very loose and easy to slide, making the graphite very soft and easy to peel off. A lightly stroked pencil on the paper may leave traces of several layers of graphene.
Scientists have conducted theoretical studies on graphene-like structures in the 1940s, but for a long time since then, efforts to produce single-layer graphene have been unsuccessful. Some people think that such a two-dimensional material is impossible at room temperature. Under stable existence. In October 2004, a paper published in the American "Science" magazine overturned this perception. Andre Heim and Konstantin Novoselov, who work at the University of Manchester in the United Kingdom, completed their "magic" with ordinary tape.
They used tape to stick the flakes from the graphite, which still contains many layers of graphene. But after sticking it repeatedly for 10 to 20 times, the flakes become thinner and thinner, eventually producing some single-layer graphene. This seemingly very simple and not high-tech method is not their first. Someone tried before, but failed to identify single-layer graphene.
Heim and Novoselov put the peeled thin slices on a silicon oxide substrate. The interference effect of light makes the thin slices appear colorful streaks under the microscope, just like the effect of an oil film on the water surface. Using this effect, they observed single-layer graphene. In this way, the first two-dimensional crystal material officially appeared. Later, people prepared some other two-dimensional materials, such as two-dimensional crystals of boron nitride and molybdenum disulfide.
Graphene has a special significance for the basic research of physics. It enables some quantum effects that could only be discussed on paper before can be verified through experiments, such as electrons ignoring obstacles and realizing ghostly crossing. But what is more interesting is its many "extreme" nature of application prospects. However, what kind of changes this two-dimensional carbon will bring to the human world cannot be predicted even by the researchers who have won the Nobel Prize.
