Researchers at IFW Dresden along with collaboration partners, have developed a new approach for producing lithium thin films. These materials are highly promising for future battery generations, as they could help improve both the lifespan and safety of energy-storage devices.
Lithium plays a central role in modern energy storage. For many applications, ultrathin, precisely controlled lithium-containing layers are crucial, such as protective coatings on cathodes or as components of solid electrolytes. These films are usually fabricated using specialized deposition techniques such as Atomic Layer Deposition (ALD). In ALD, very thin layers form through alternating evaporation and surface reactions of a chemical precursor on a substrate. However, ALD of lithium-containing films encounters a major obstacle: suitable lithium precursors are scarce. Many common lithium compounds tend to aggregate into larger molecular clusters. As a result, they evaporate poorly and react uncontrollably, making them unsuitable for reliable thin-film growth.
Mononuclear lithium complex: volatile yet thermally stable
A team led by researchers at IFW Dresden has now demonstrated a way around this problem. In their current work, the scientists developed a mononuclear lithium complex that is both volatile and thermally stable—an unusual and highly valuable combination in lithium chemistry. The key lies in a tailored ligand from carbene chemistry. A N-heterocyclic carbene (NHC) “shields” the lithium center so effectively that it remains a single well-defined molecule instead of forming clusters. This significantly improves its evaporability and makes the compound highly compatible with ALD processes.
As a proof-of-concept, the team used the new precursor to produce lithium-silicate thin films by ALD. The resulting films exhibit clean, well-controlled growth and contain no residual ligand. This establishes a new, stable ALD pathway to lithium-containing materials, which are highly relevant to battery technologies. Beyond the specific lithium system, the study provides a new technological foundation: it describes the first NHC-stabilized ALD precursor for an alkali metal. The work also introduces a general principle—elements prone to clustering can be made usable for thin-film processes through targeted ligand design—opening the door to ALD precursors for other challenging materials.
The results were published in Angewandte Chemie International Edition, where the paper was highlighted as a Hot Paper.
Original Publication:
Rare Mononuclear Lithium–Carbene Complex for Atomic Layer Deposition of Lithium Containing Thin Films
https://doi.org/10.1002/anie.202513066
Contact
Scientific contact:
Prof. Dr. Anjana Devi
a.devi[at]ifw-dresden.de
Dr. Jorit Oberlüneschloß
jorit.obenlueneschloss[at]rub.de
Press Contact
Patricia Bäuchler
p.baeuchler[at]ifw-dresden.de
