Laser pulses could help develop the next generation of high-capacity batteries

Recently, King Abdullah University of Science and Technology (KAUST) has reported a research result that may help improve the anode material of the next generation of batteries.

KAUST demonstrated the use of laser pulses to modify the structure of a potential alternative electrode material known as MXene, improving its energy capacity and other key properties.

In the study, the scientists explained that graphite contains flat layers of carbon atoms, and lithium atoms are stored between these layers during battery charging, a process known as "embedding." The "MXene" material structure also contains layers that can hold lithium, but these layers are made of transition metals such as titanium or molybdenum combined with carbon or nitrogen atoms, which makes the material highly conductive.

The surface of these layers also has additional atoms, such as oxygen or fluorine. The "MXene" material structure based on molybdenum carbide has a particularly good lithium storage capacity, but its performance also quickly deteriorates after repeated charge and discharge cycles.

By Husam N. The KAUST team, led by Alshareef and Zahra Bayhan, found that this degradation is caused by chemical changes that form molybdenum oxide in the structure of MXene.

To solve this problem, they used infrared laser pulses to create small "nanodots" of molybdenum carbide in the "MXene" material structure, a process known as "laser scribing." These nanodots, about 10 nanometers wide, are connected by a carbon material to layers of the "MXene" material structure.

This offers several benefits: First, the nanodots provide additional storage capacity for lithium and speed up the charge-discharge process. The laser treatment also reduces the oxygen content of the material, helping to prevent the formation of problematic molybdenum oxide. Finally, the strong connection between the nanodots and the layers improves the electrical conductivity of the "MXene" material structure and stabilizes its structure during charging and discharging.

"This provides a cost-effective and fast way to tune battery performance," Bayhan said in a media statement.

The researchers made an anode out of laser-written material and tested it through more than 1,000 charge-discharge cycles in a lithium-ion battery. With the nanodots, the material has an electrical storage capacity four times higher than the original MXene, almost reaching the theoretical maximum capacity of graphite. The laser-burned material also showed no loss of capacity in cycle tests.

Given these results, they believe that laser engraving could be used as a general strategy to improve the performance of other "MXenes" material structures. For example, this could help develop a new generation of rechargeable batteries that use metals that are cheaper and more abundant than lithium. In addition, unlike graphite, the MXenes material structure can also embed sodium and potassium ions.

Source: OFweek