Credit: Dalian Institute of Chemical Physics (DICP)
Researchers have developed a novel production method to fabricate transition metal telluride nanosheets using chemical solutions to create atomically thin sheets. Transition metal telluride (TMT) nanosheets have long intrigued researchers as these two-dimensional materials have unusual properties that show promise for fundamental research and countless other applications.
The fabrication method, published in Nature, uses chemical solutions to peel off layers from parent compounds to create two-dimensional sheets made of tellurium. These sheets display a range of states including semi-metallic, semiconducting, insulating, superconducting, and additional exotic states. The properties offer a range of potential applications with current interest being centered around their use as novel electrode materials in batteries and supercapacitors.
"The list of industries that would enjoy significant efficiency improvements from the mass production of TMT nanosheets is extremely long," said WU Zhong-Shuai, a chemist with the Dalian Institute of Chemical Physics (DICP), Chinese Academy of Sciences. “This is why this 2D material is potentially so exciting.”
Previous attempts to produce TMT nanosheets at scale have failed to preserve the high crystallinity within a large ultrathin nanosheet. The team believes they have solved this problem with a simplified lithiation, hydrolysis, and exfoliation method. To fabricate the sheets, the team first prepares a large quantity of telluride crystals via chemical vapor transport. Once added to the reaction vessel, the compound carried by the vapor can deposit and form crystals on a cooler surface allowing for a controlled growth of crystals of the desired compound. The crystals are then mixed with lithium borohydride to form a lithiated compound before being exfoliated to strip the lithiated crystals into nanosheets within seconds.
The entire process occurs in under ten minutes and produces high-quality TMT nanosheets with very high yields. Analysis of the sheets demonstrated their promising charge storage, high-rate capacity, and stability, making them a promising material for use in lithium batteries and micro-supercapacitors. The team intends to refine their lithiation and exfoliated stages but feels the method could be ready for commercialization.