Crab consumers know what crustacean cores have to offer, but scientists are increasingly turning to animal exoskeletons for new medicine and biotechnology.
Much of the interest has focused on chitosan, a derivative of the polysaccharide polymer chitin, which is abundant in crustacean shells, insect exoskeletons, and fungal cell walls. But scientists believe that upcycling shell waste into hard carbon could form a key part of the electrical circuitry of sodium-based rechargeable batteries, a sustainable alternative to current lithium technology. I discovered that there is
Researchers found that by producing hard carbon from the shell, it could serve as an anode in sodium-ion batteries. Heating the shell to temperatures above 1,000° F (538 °C) converts the shell to carbon and tin sulfide (SnS2) or iron sulfide (FeS2). This formed a viable sodium-ion anode, or cathode, for the battery.
Sodium Ion Battery (SIB) is a new technology and sustainable alternative to Lithium Ion Battery (LIB). Although chemically similar to lithium, sodium ions are larger and require a different anode than those usually made of graphite. This is where the team of Yun Chen, Yue Zhao, Hongbin Liu and Tingli Ma found a compatible alternative to crab.
Crab carbon provided a porous, fibrous, high-surface-area anode that enhanced electrical conductivity and sodium-ion transport capacity. The team then found that in that model battery, both the tin and iron composites had adequate charge capacities of at least 200 cycles. While not in the realm of lithium batteries, it is a positive step towards more sustainable battery technology.
Last year, the World Economic Forum highlighted the many issues surrounding the continued viability of lithium mining, predicting that the finite resource could run out as early as 2025. This problem is exacerbated by the environmental impact and the high cost of water required for lithium extraction. , many of the world’s largest sources of minerals – Australia, South America – are also located in drought-prone regions. The race to develop it continues.
The study comes six months after scientists discovered that a chitosan-derived gel electrolyte could power zinc batteries, and was not corrosive or flammable, such as those found in ion-transporting electrolyte solutions in current lithium batteries. Proven to be far more sustainable with no harsh chemicals.
Chitin and chitosan have previously played important roles in self-healing paints, biotechnology transistors, plastic substitutes, influenza virus filters, and antiviral drugs. Conversely, scientists are working hard to find alternatives to the problem of procuring horseshoe crab amoeba his lysate (LAL) from horseshoe crab blood. LAL has been an integral part of the development of safe vaccines and other injectables for over 40 years.
Crab carbon can only be produced from by-products, and the team believes that moving away from lithium will have minimal impact on animal populations, in addition to the widespread environmental benefits. As the cost of lithium raw materials rises, it is also a more economical alternative.
“This study provides an efficient route to build high-specific-energy sodium-ion batteries utilizing low-cost waste feedstocks,” said the authors.
The study was published in a journal ACS Omega.
Source: American Chemical Society
