Today's KNOWLEDGE Share : Cobalt-free batteries could power cars of the future

Today's KNOWLEDGE Share

Cobalt-free batteries could power cars of the future

MIT chemists developed a battery cathode based on organic materials, which could reduce the EV industry’s reliance on scarce metals.

Many electric vehicles are powered by batteries that contain cobalt a metal that carries high financial, environmental, and social costs.

MIT researchers have now designed a battery material that could offer a more sustainable way to power electric cars. The new lithium-ion battery includes a cathode based on organic materials, instead of cobalt or nickel (another metal often used in lithium-ion batteries).

In a new study, the researchers showed that this material, which could be produced at much lower cost than cobalt-containing batteries, can conduct electricity at similar rates as cobalt batteries. The new battery also has comparable storage capacity and can be charged up faster than cobalt batteries, the researchers report.

“I think this material could have a big impact because it works really well,” says Mircea Dincă, the W.M. Keck Professor of Energy at MIT. “It is already competitive with incumbent technologies, and it can save a lot of the cost and pain and environmental issues related to mining the metals that currently go into batteries.”

Alternatives to cobalt

“Cobalt batteries can store a lot of energy, and they have all of features that people care about in terms of performance, but they have the issue of not being widely available, and the cost fluctuates broadly with commodity prices. And, as you transition to a much higher proportion of electrified vehicles in the consumer market, it’s certainly going to get more expensive,” Dincă says.

Because of the many drawbacks to cobalt, a great deal of research has gone into trying to develop alternative battery materials. One such material is lithium-iron-phosphate (LFP), which some car manufacturers are beginning to use in electric vehicles. Although still practically useful, LFP has only about half the energy density of cobalt and nickel batteries.

Another appealing option are organic materials, but so far most of these materials have not been able to match the conductivity, storage capacity, and lifetime of cobalt-containing batteries. Because of their low conductivity, such materials typically need to be mixed with binders such as polymers, which help them maintain a conductive network. These binders, which make up at least 50 percent of the overall material, bring down the battery’s storage capacity.

About six years ago, Dincă’s lab began working on a project, funded by Lamborghini, to develop an organic battery that could be used to power electric cars. While working on porous materials that were partly organic and partly inorganic, Dincă and his students realized that a fully organic material they had made appeared that it might be a strong conductor.

This material consists of many layers of TAQ (bis-tetraaminobenzoquinone), an organic small molecule that contains three fused hexagonal rings. These layers can extend outward in every direction, forming a structure similar to graphite. Within the molecules are chemical groups called quinones, which are the electron reservoirs, and amines, which help the material to form strong hydrogen bonds.

Those hydrogen bonds make the material highly stable and also very insoluble. That insolubility is important because it prevents the material from dissolving into the battery electrolyte, as some organic battery materials do, thereby extending its lifetime.

“One of the main methods of degradation for organic materials is that they simply dissolve into the battery electrolyte and cross over to the other side of the battery, essentially creating a short circuit. If you make the material completely insoluble, that process doesn’t happen, so we can go to over 2,000 charge cycles with minimal degradation,” Dincă says.

Strong performance

Tests of this material showed that its conductivity and storage capacity were comparable to that of traditional cobalt-containing batteries. Also, batteries with a TAQ cathode can be charged and discharged faster than existing batteries, which could speed up the charging rate for electric vehicles.

To stabilize the organic material and increase its ability to adhere to the battery’s current collector, which is made of copper or aluminum, the researchers added filler materials such as cellulose and rubber. These fillers make up less than one-tenth of the overall cathode composite, so they don’t significantly reduce the battery’s storage capacity.

These fillers also extend the lifetime of the battery cathode by preventing it from cracking when lithium ions flow into the cathode as the battery charges.

The primary materials needed to manufacture this type of cathode are a quinone precursor and an amine precursor, which are already commercially available and produced in large quantities as commodity chemicals. The researchers estimate that the material cost of assembling these organic batteries could be about one-third to one-half the cost of cobalt batteries.

Lamborghini has licensed the patent on the technology. Dincă’s lab plans to continue developing alternative battery materials and is exploring possible replacement of lithium with sodium or magnesium, which are cheaper and more abundant than lithium.

Source:MIT News

Today's KNOWLEDGE Share:Complex Morphology

Today's KNOWLEDGE Share

Injection Molding creates non-monotonic crystallinity gradients through the thickness, and corresponding non monotonic elastic modulus.

On one hand the rapid quench of the skin (combined with fountain flow) reduces crystallinity of the most outer layers leading to typically half the nominal modulus ( PP data).

The high shear just below (frozen skin) will produce strong "flow induced nucleation" and more crystallinity ( and oriented structures). These layers can be 4X stiffer than the skin in PP.
Finally the core section undergoes a more quiescent crystallization with slower cooling and shear rates and will have "average" crystallinity, larger non-oriented crystals and pretty much the data-sheet kind of modulus.

Source:Vito leo

Today's KNOWLEDGE Share :Biochar from Green Algae:

Today's KNOWLEDGE Share

Biochar from Green Algae: A Dual-Solution for Green Energy

A new study has harnessed the power of a humble green macroalgae, dry, to create a biochar with surprising capabilities. This biochar acts as a dual-threat in the world of green energy, functioning both as an efficient hydrogen catalyst and an electrocatalyst for fuel cells.

The research, published in Fuel, highlights the potential of E. intestinalis as a sustainable and cost-effective resource for clean energy solutions. Traditionally, hydrogen production from sodium borohydride relies on expensive metal catalysts. This biochar, however, offers a promising alternative, significantly boosting hydrogen production rates.

But the biochar’s talents don’t stop there. It also shines as an electrocatalyst for methanol fuel cells. These cells hold immense potential for clean energy generation, but often require expensive platinum-based catalysts. The E. intestinalis biochar paves the way for a more affordable and environmentally friendly option.

The key to unlocking the biochar’s dual potential lies in optimizing its creation process. The researchers employed Taguchi’s experimental design, a robust method for identifying the ideal combination of factors for superior performance. By analyzing various parameters like acid concentration, impregnation times, and burning temperatures, they identified the settings that yielded the most effective biochar.

This study is significant for several reasons:

Sustainability: E. intestinalis is readily available and grows rapidly, making it a sustainable source for biochar production.

Cost-effectiveness: Compared to traditional metal catalysts, the biochar offers a more affordable solution for both hydrogen production and fuel cell applications.

Environmental benefits: Replacing fossil fuels with hydrogen and methanol fuel cells reduces greenhouse gas emissions,contributing to a cleaner environment.

Overall, this research opens exciting possibilities for utilizing E. intestinalis biochar in the development of clean and sustainable energy solutions. Its dual functionality and impressive performance make it a valuable asset in the fight against climate change and the quest for renewable energy sources.

Further research could explore:

Scaling up the biochar production process for large-scale applications.

Investigating the long-term durability and stability of the biochar in both hydrogen production and fuel cell operation.

Exploring the potential of other readily available biomaterials for creating similar dual-functional catalysts.

Source:biochartoday

Today's KNOWLEDGE Share : SEM Vs TEM

Today's KNOWLEDGE Share

SEM Vs TEM:

Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) are the two most common forms of electron microscopy. While both techniques share the same fundamental principles, there are several distinct differences in their instrumentation and what signals are analyzed. In an SEM, the secondary electron (SE) and backscattered electrons (BSE) are used to acquire images of a sample’s surface whereas in a TEM, the transmitted electrons are detected to produce a projection-image through a sample’s interior.

To make a meaningful comparison between SEM and TEM, it’s important to note what all electron microscopes have in common. The “column” of all electron microscopes contains a series of components that are responsible for core functions. 

These include:

The electron source – produces the electron beam.

Condenser lenses – directs the beam onto the sample.

Objective lens – containing the most important electromagnetic lens in the column, is responsible for forming an image of the transmitted electrons (TEM) or for forming the final focused probe that is scanned across the sample surface (SEM).

Sample chamber – holds the sample and determines the size of the sample that can be analyzed.

Detectors – collect signals to produce images.

Source:Nanoscience

Today's KNOWLEDGE Share:Radical Chain Reactions

Today's KNOWLEDGE Share

New Method Uses Common Plastics to Initiate Radical Chain Reactions:

A team led by researchers at the Institute for Chemical Reaction Design and Discovery, Hokkaido University has developed a method that uses common plastic materials instead of potentially explosive compounds to initiate radical chain reactions.

This approach significantly increases the safety of the process while also providing a way to reuse common plastics such as polyethylene and polyvinyl acetate. These findings have been published in the Journal of the American Chemical Society.

Utilizes Plastic Waste for Dehalogenation:

Researchers utilized a ball mill, a machine that rapidly shakes a steel ball inside a steel jar to mix solid chemicals. When the ball slams into the plastic, the mechanical force breaks a chemical bond to form radicals, which have a highly reactive, unbonded electron. These radicals facilitated a self-sustaining chain reaction that promotes dehalogenation i.e., the replacement of a halogen atom with a hydrogen atom of organic halides.

“The use of commodity plastics as chemical reagents is a completely new perspective on organic synthesis,” said associate professor Koji Kubota. “I believe that this approach will lead to not only the development of safe and highly efficient radical-based reactions, but also to a new way to utilize waste plastics, which are a serious social problem.”

The reuse of waste plastic was demonstrated by adding plastic shreds of a common grocery bag to the ball mill jar and successfully carrying out the reaction. The team also showed their method could be applied to the treatment of highly toxic polyhalogenated compounds, which are widely used in industry. Polyethylene was employed to initiate a radical reaction that removed multiple halogen atoms from a compound commonly used as a flame retardant, thus reducing its toxicity.

Researchers anticipate this method will garner the attention of industry due to advantages in cost and safety.

“Our new approach using stable, cheap and abundant plastic materials as initiators for radical chain reactions holds the significant potential to foster the development of industrially attractive, safe and highly efficient chemical processes,” commented professor Hajime Ito.

Source: Hokkaido University/Omnexus-specialchem

Here are the winners of India’s first green hydrogen and electrolyser subsidy auctions

The results of India’s first auctions for green hydrogen and electrolyser subsidies have been published, with industrial conglomerate Reliance a big winner in both tenders.

The green hydrogen auction, which offered a per-kilogram maximum of 50 rupees ($0.60) in the first year, 40 rupees in the second, and 30 rupees in the third, awarded subsidies to eight companies (see table below) out of thirteen bidders.

Mumbai-based Avaada, Singapore-headquartered Sembcorp and GH4India — a joint venture between Indian Oil, ReNew, and Larsen & Toubro — all lost out on their bids, which applied for subsidies in all three years.

In addition, two companies, UPL Limited and CESC Projects Limited, were included in the list of winners despite not bidding for any subsidies at all.

This bulked up the awarded production capacity to a total of 412,000 tonnes of H2 per year, just below the cap of 450,000 tonnes per year.

India is aiming to produce five million tonnes of green hydrogen annually by 2030, with the cost of production reaching parity with grey H2 made from unabated natural gas in the latter half of this decade.

However, the subsidy per kilogram is extremely low compared to those offered in the US and Europe, with analysts cautioning that in order to compete with grey, the cost of both round-the-clock renewable electricity and electrolyser prices must fall.

Meanwhile, the auction for electrolyser manufacturing subsidies, which offered a maximum incentive of 4,440 rupees per kilowatt of capacity sold, assuming local content and domestic sales conditions are met, was even more competitive.

Out of 21 bids — 14 for any technology and seven specifically for Indian-developed electrolysers — only eight winners were announced (see table below), meeting the cap of 1.5GW of manufacturing capacity.

While Adani, the industrial conglomerate founded by billionaire Gautam Adani, had bid in capacity for both tranches, it only secured partial subsidy for the latter.

US-based Ohmium already has a 500MW electrolyser factory in operation in India, with plans to expand this to 2GW.

Belgian manufacturer John Cockerill also aims to build a 2GW plant in the country, in partnership with one of India’s biggest clean-energy developers, Greenko; while Indian conglomerate L&T (Larsen and Toubro) has agreements in place to use the technology of two European electrolyser makers — France’s McPhy and Norway’s HydrogenPro.

Fellow Indian conglomerate Reliance Industries — run by Asia’s richest man, Mukesh Ambani — plans to build a 1GW factory producing low-cost electrolysers designed by Denmark’s Stiesdal.(Copyright)

Source:hydrogeninsight

Study Finds High Concentration of Nanoplastics in Bottled Water

Using newly refined technology, researchers have entered a whole new plastic world: the poorly known realm of nanoplastics, the spawn of microplastics that have broken down even further. For the first time, they counted and identified these minute particles in bottled water.

They found that on average, a liter contained some 240,000 detectable plastic fragments—10 to 100 times greater than previous estimates, which were based mainly on larger sizes.

Yet to Discover Possible Effects on Human Body

Nanoplastics are so tiny that, unlike microplastics, they can pass through intestines and lungs directly into the bloodstream and travel from there to organs including the heart and brain. They can invade individual cells, and cross through the placenta to the bodies of unborn babies. Medical scientists are racing to study the possible effects on a wide variety of biological systems.

“Previously this was just a dark area, uncharted. Toxicity studies were just guessing what’s in there,” said study coauthor Beizhan Yan, an environmental chemist at Columbia Climate School’s Lamont-Doherty Earth Observatory. “This opens a window where we can look into a world that was not exposed to us before.”

Worldwide plastic production is approaching 400 million metric tons a year. More than 30 million tons are dumped yearly in water or on land, and many products made with plastics including synthetic textiles shed particles while still in use. Unlike natural organic matter, most plastics do not break down into relatively benign substances; they simply divide and redivide into smaller and smaller particles of the same chemical composition. Beyond single molecules, there is no theoretical limit to how small they can get.

Microplastics are defined as fragments ranging from 5 millimeters (less than a quarter inch) down to 1 micrometer, which is 1 millionth of a meter, or 1/25,000th of an inch. (A human hair is about 70 micrometers across.) Nanoplastics, which are particles below 1 micrometer, are measured in billionths of a meter.

110,000 to 370,000 Plastic Fragment in Each Liter

Plastics in bottled water became a public issue largely after a 2018 study detected an average of 325 particles per liter; later studies multiplied that number many times over. Scientists suspected there were even more than they had yet counted, but good estimates stopped at sizes below 1 micrometer—the boundary of the nano world.

“People developed methods to see nano particles, but they didn’t know what they were looking at,” said the new study’s lead author, Naixin Qian, a Columbia graduate student in chemistry. She noted that previous studies could provide bulk estimates of nano mass, but for the most part could not count individual particles, nor identify which were plastics or something else.

The new study uses a technique called stimulated Raman scattering microscopy, which was co-invented by study coauthor Wei Min, a Columbia biophysicist. This involves probing samples with two simultaneous lasers that are tuned to make specific molecules resonate. Targeting seven common plastics, the researchers created a data-driven algorithm to interpret the results. “It is one thing to detect, but another to know what you are detecting,” said Min.

The researchers tested three popular brands of bottled water sold in the United States (they declined to name which ones), analyzing plastic particles down to just 100 nanometers in size. They spotted 110,000 to 370,000 plastic fragment in each liter, 90% of which were nanoplastics; the rest were microplastics. They also determined which of the seven specific plastics they were, and charted their shapes—qualities that could be valuable in biomedical research.

Common Plastics Found: PET, PA, PS, PVC and PMMA

One common one was polyethylene terephthalate or PET. This was not surprising, since that is what many water bottles are made of. (It is also used for bottled sodas, sports drinks and products such as ketchup and mayonnaise.) It probably gets into the water as bits slough off when the bottle is squeezed or gets exposed to heat. One recent study suggests that many particles enter the water when you repeatedly open or close the cap, and tiny bits abrade.

However, PET was outnumbered by polyamide, a type of nylon. Ironically, said Beizhan Yan, that probably comes from plastic filters used to supposedly purify the water before it is bottled. Other common plastics the researchers found: polystyrene, polyvinyl chloride and polymethyl methacrylate, all used in various industrial processes.

A somewhat disturbing thought: the seven plastic types the researchers searched for accounted for only about 10% of all the nanoparticles they found in samples; they have no idea what the rest are. If they are all nanoplastics, that means they could number in the tens of millions per liter. But they could be almost anything, “indicating the complicated particle composition inside the seemingly simple water sample,” the authors write. “The common existence of natural organic matter certainly requires prudent distinguishment.”

The researchers are now reaching beyond bottled water. “There is a huge world of nanoplastics to be studied,” said Min. He noted that by mass, nanoplastics comprise far less than microplastics, but “it’s not size that matters. It’s the numbers, because the smaller things are, the more easily they can get inside us.”

To Further Test Tap Water and Snow for Microplastics:

Among other things, the team plans to look at tap water, which also has been shown to contain microplastics, though far less than bottled water. Beizhan Yan is running a project to study microplastics and nanoplastics that end up in wastewater when people do laundry—by his count so far, millions per 10-pound load, coming off synthetic materials that comprise many items. (He and colleagues are designing filters to reduce the pollution from commercial and residential washing machines.) The team will soon identify particles in snow that British collaborators trekking by foot across western Antarctica are currently collecting. They also are collaborating with environmental health experts to measure nanoplastics in various human tissues and examine their developmental and neurologic effects.

“It is not totally unexpected to find so much of this stuff,” said Qian. “The idea is that the smaller things get, the more of them there are.”

The study was coauthored by Xin Gao and Xiaoqi Lang of the Columbia chemistry department; Huipeng Deng and Teodora Maria Bratu of Lamont-Doherty; Qixuan Chen of Columbia’s Mailman School of Public Health; and Phoebe Stapleton of Rutgers University.

Source: Columbia Climate School