Ethylene carbonate, also known as ethylene carbonate, 1,3-dioxolane-2-one, 1,3-dioxolane ethylene carbonate...
Its chemical formula is 'c3h4o3'. It is a crystalline solid at room temperature, but turns into a transparent colorless liquid when the temperature is greater than 35C. It is an organic solvent with excellent performance and can dissolve a variety of polymers. It is used in fertilizers, fibers,
Pharmaceutical and organic synthesis industries.
As a materials researcher, Xu Chuan has some understanding of the compound ethylene carbonate, but not much.
After all, his material research in his previous life mainly focused on physical materials, while ethylene carbonate belongs to the category of chemical materials.
However, it is not difficult for him to understand the properties of a material and find another additive that can control it.
All things are interdependent, and so are materials.
Different materials have different chemical and physical properties, the blending of molecules, finding order in disorder, finding simplicity and beauty in complexity, either destruction or rebirth.
For example, amorphous alloy materials look extremely hard. However, they are not absolutely orderly. They are in a never-ending flow, just like Van Gogh's "Starry Night". If you look carefully, you will see that they are always moving while seemingly motionless.
move.
This is the charm of materials science.
...
"Ethylene carbonate: the molecular formula is c3h4o3, the molar refractive index in the molecular structure is 17.17, the surface tension is 37.3, the dipole moment is 10-2?cm3, and the polarizability is 6.80..."
"Number of hydrogen bond donors: 0, number of hydrogen bond acceptors: 3, number of rotatable chemical bonds: 0, number of tautomers: none, topological molecule polar surface area 35.5, number of covalent bond units: 1...
..."
"miscible with hot water above 40c, alcohol, benzene, chloroform, ethyl acetate, acetic acid and other items. Insoluble in dry ether, carbon disulfide, carbon tetrachloride, petroleum ether, etc...
"
In the laboratory, Xu Chuan listed out all the information about ethylene carbonate bit by bit.
Whether it is its chemical and physical properties or various previous studies.
These things are of great help in finding materials to control ethylene carbonate.
In fact, when looking for a material to control ethylene carbonate, he could ask other chemical researchers for help.
For those chemical materials researchers who have been immersed in this field for many years, it is not too difficult to find several materials that meet the requirements.
However, Xu Chuan had another idea. He wanted to try it and see if mathematics could be integrated into materials science calculations.
Just as others speculate that his development of nuclear radiation-resistant materials and lithium battery materials relied on his strong mathematical abilities.
Only he himself knows that it is not.
Today, what Xu Chuan wants to do is to take this step and use mathematics to help him complete this work.
For chemical reactions, in textbooks it is the transformation of chemical formulas line by line; in the laboratory, it is the breaking of old chemical bonds and the formation of new chemical bonds.
For example, the essence of a redox reaction is the gain and loss of electrons outside the nucleus, and the structure of the atom itself changes.
The essence of the metathesis reaction is the rearrangement of atoms, that is, the arrangement and combination of multiple atoms changes.
But in fact, its deeper essence is the flow of electron clouds.
To determine whether a chemical reaction can occur, it must be confirmed from various aspects such as thermodynamics, kinetics, enthalpy change, entropy change, free energy (gibbs free energy), activation energy, etc.
In fact, strictly speaking, the current development of chemistry is not perfect.
Because we often cannot explain even the simplest chemical reactions with theory, many theories are phenomenological.
If we follow the chain of explanations from chemistry, we will eventually end up with explanations from physics.
Therefore physics is the most basic subject in natural science (mathematics is not a natural subject!).
Many people mistakenly think that chemistry is the most basic, because chemical bonds are essentially an electrical interaction, which belongs to the electromagnetic interaction among the four basic forces. The progress of chemical reactions is also related to the movement and collision of molecules.
Of course, the potential of chemistry is very deep, and there is huge value in exploring it further.
And if you look at the deep nature of chemistry, there is no doubt that mathematics can be applied.
For example, the most common chemical reaction rates can be described by calculus equations. Mathematical equations can be solved using numerical methods to determine reaction rate constants and other parameters.
For example, wave function theory, group theory, etc. are used to describe electronic structure and reaction mechanisms.
Or molecular dynamics simulation, which uses computer mathematics to simulate and study the laws of material motion. It involves a lot of knowledge in calculus, probability statistics, and optimization algorithms.
In addition, there are various aspects of thermodynamics, analytical chemistry, etc., which can all be carried out through mathematics.
Theoretically, if you know the information and conditions related to the materials that need to undergo chemical reactions, you can completely simulate the entire reaction process through mathematics.
This sounds weird, but the theory works.
Of course, this is actually an impossible thing, at least not yet.
What Xu Chuan wants to do is to take the first step towards this impossible thing.
Ethylene carbonate is a good test target.
...
"Considering the polymer solvents and positive and negative electrode materials used in the electrolyte, there are not many options for additives used to control ethylene carbonate."
"Most alkaline compounds and alcohol compounds can basically be eliminated. These compounds will react with ethylene carbonate to generate various substances harmful to the battery. Not only will they corrode the positive and negative electrodes, they will not be recycled."
"Then there are not many options left. Ketone, fluorinated, and cyclic materials can be considered."
"After screening based on the reversibility conditions, ketone compounds with a carbonyl group connected to two hydrocarbon groups are a good choice."
"However, the range of ketones is still too large and needs to be narrowed down..."
In the laboratory, Xu Chuan kept mumbling to himself, and the ballpoint pen in his hand continued to record data item by item on the A4 paper.
He is first doing a rough screening of available additives based on some basic chemical reactions, and then conducting reaction simulations and selections through mathematics.
This is a very challenging road. Although it is not untrodden, it is not deeply explored. The path with an end in sight is full of thorns in the unknown fog, and one needs to muster the courage to move forward.
Fortunately, he has never lacked the courage to explore and face difficulties.
...
In the laboratory, Xu Chuan continues to improve his theories and data.
On the other hand, testing of new artificial SEI films and ethylene carbonate content are also ongoing.
Five or six days passed in the blink of an eye.
While Xu Chuan is still looking for suitable materials, the tests at the Chuanhai Materials Laboratory have basically been completed.
"Director Fan, this is the experiment and test data of these days. From the experiments of these days, it is most suitable to reduce the content of ethylene carbonate to about 67.3% of the original basis without changing other materials and additives.
a number."
In the laboratory, Yu Zhen, the official researcher who was originally responsible for the research of artificial SEI thin films, handed over a thick plate of report materials.
Fan Pengyue nodded and reached out to take it: "Thank you for your hard work."
Yu Zhen shook his head and replied: "Ashamed to say, we have not played any role in the research and development of lithium battery materials this time."
"From the initial theoretical and experimental process to the later solution to the artificial SEI film problem, as well as the discovery of the problem of ethylene carbonate interfering with lithium dendrites and lithium precipitation, it was all handled by the boss."
"We just conducted the experiment according to his request. This kind of experiment can be done by any master's student who has done lithium battery experiments."
Hearing this, Fan Pengyue also sighed.
"He is indeed abnormal. At the age of 21, he won the highest honors in mathematics and physics at the same time. This is no longer a person from the same world as us."
"I believe that no matter which industry field he is in, he can show the most terrifying ability."
After a pause, Fan Pengyue continued: "Did you know? When I was still studying for a Ph.D., I was working on a tungsten diselenide material project with my supervisor. I encountered a problem that almost made my supervisor give up the project."
"The junior fellow at the back not only helped solve this problem, but also used mathematics to discover the root cause of the problem and find a solution."
"And the results of that project are worth billions of dollars!"
"What's more important is that he was still in his freshman year at the time."
Hearing this, Yu Zhen took a breath.
He knew who Fan Pengyue's mentor was.
After all, several months have passed, and ordinary chats and conversations are enough for everyone to understand each other.
Not only their boss, the airborne supervisor in front of them is actually not bad either. As a disciple of an academician of the Academy of Sciences, his interpersonal relationships and status are not comparable to those of them.
For a project that even an academician almost gave up on, the difficulties must have been fatal.
Even though I knew that the double Nobel Prize and Fields Medal winners were not from the same world as them, yet in my freshman year, I was able to participate in a project worth billions of dollars and solve fatal problems.
This talent is beyond description.
But thinking back, Yu Zhen suddenly felt it was reasonable.
If he were not such a monster, how could he solve problems that even academicians could not solve and win the Nobel Prize and the Fields Medal at the age of twenty-one? These are the two most authoritative awards in academia.
Although he was shocked, this mathematical ability also made Yu Zhen a little curious.
He couldn't help but ask: "You think, if you are good at mathematics, are you really that good? Can a field of mathematics such as materials, which is difficult to apply, also be solved through mathematics?"
Hearing this question, Fan Pengyue was silent for a moment. After thinking about it, he replied with some confusion: "I don't know. Maybe it is for him?"
After a pause, he added cautiously: "But I have never seen this level of mathematical applications from other mathematics professors."
"Maybe he is special."
.......
On the other side, in the office, Xu Chuan was lying in front of the table, writing with the ballpoint pen in his hand.
Staring at the data on the manuscript paper, Xu Chuan fell into deep thought.
"From the data point of view, methyl ethyl ketone is a good choice. Based on the chemical properties, it is speculated that it can play a certain role in inhibiting ethylene carbonate."
"As we all know, the reason why ethylene carbonate plays a great role in lithium-ion batteries is that it can form a tightly ordered li-ec solvation configuration with li through solvation, thereby making the ec-containing electrolyte
More stable during the cycle.”
"Since the 'li - ethylene carbonate solvent' configuration has higher stability than other solvated lithium ions, such as ethyl methyl carbonate and other materials, 'li - ethylene carbonate solvent' is added to the electrolyte
After the components are added, the cycle performance and voltage polarization phenomenon of the battery can be significantly improved."
"This not only improves the stability of the electrolyte, but at the same time, the reduction products of ethylene carbonate help to form a stable solid electrolyte interface film, making the electrolyte more stable during the circulation process."
"Methyl ethyl ketone can be inside and weaken the lithium precipitation phenomenon of the negative electrode to a certain extent through the deposition/extraction behavior of lithium ions."
This chapter is not finished yet, please click on the next page to continue reading the exciting content! "As for the specific situation, experiments still need to be carried out. After all, there must be some differences between the calculated data and the actual application."
Thinking about it, Xu Chuan shook his head again, looked at the manuscript paper on the table and let out a long sigh of relief.
These days, he has put aside other projects and concentrated on studying this problem. In terms of progress, there is indeed some progress, but not much.
So far, he has only found one material that may be suitable.
He underestimated the various associated phenomena that may occur in chemical reactions. These things can exhaust a person to death.
"Perhaps I should come up with a mathematical model?"
In his mind, Xu Chuan turned his thoughts to another aspect.
Although a mathematical model cannot accurately predict the properties of untested material samples and possible chemical linkage phenomena, it can provide users with a certain reference.
For example, narrowing the scope of the experiment from a probabilistic sense.
Very early on, when he was still a freshman, he made a mathematical model for his tutor Chen Zhengping on the tungsten diselenide material project, and then quickly helped find problems in the experimental process and locked in the best reducing substance.
concentration.
It can be said that in the process of material development, a mathematical model still plays a great role.
It's just that he doesn't have that much time to do this now.
It should be possible to create a mathematical model for the study of chemical materials, but it will definitely be much more difficult than the one he used to make for his mentor Chen Zhengping.
It can even be said to be one heaven and one earth.
After all, the tungsten diselenide material project is just a material. Even if there are conditions such as reducing agent, temperature, and air pressure, it is not very complicated.
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But chemistry is different, this kind of mathematical model for the exploration of chemical materials, the complexity is simply beyond the sky.
Even if he brings a team of more than a dozen people to write it, it may take several months.
Of course, if successful, it would bring great convenience to his future chemical experiments.