Coherent Solution‐phase Synthesis of a Germanium‐Graphitic Nanocomposite and Its Evaluation for Lithium‐Ion Battery Anodes: Non‐innocent Role of the Mashima Reagent

• Published in: Chemistry, an Asian journal Vol. 15; no. 5; pp. 585 - 589
• Main Authors: Akula, Naveenkumar, Sharma, Neha, Lohegaonkar, Apurva, Ogale, Satishchandra B., Majumdar, Moumita
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 02.03.2020
• Subjects: Anodes; Argon; Chemistry; colloidal synthesis; Germanium; Germanium chlorides; hot-injection; Lithium-ion batteries; Nanocomposites; Nanocrystals; organosilicon reducing agent; Reagents; organosilicon reducing agent; colloidal synthesis; hot-injection; lithium-ion batteries; germanium
• ISSN: 1861-4728; 1861-471X
• DOI: 10.1002/asia.201901704

The organosilicon reagent 1,4‐bis‐(trimethylsilyl)‐1,4‐diaza‐2,5‐cyclohexadiene 2 plays the binary role of the simultaneous reduction of GeCl2.dioxane 1 dissolved in oleylamine to Ge nanocrystals and the formation of graphitic sheets under hot‐injection conditions. This colloidal synthetic route to germanium nanocrystals embedded on N‐doped graphitic nanosheets Ge/NG is free of any template or catalyst and involves easy purification techniques. The Ge/NG/C obtained after carbonization has been explored for anode performance in lithium‐ion batteries. Both Ge/NG and Ge/NG/C can be obtained on a gram scale and are bottleable under argon for months. Graphitic nanosheets were obtained coeval with the Ge nanocrystals under the hot‐injection conditions from a mixture of GeCl2.dioxane, oleylamine and 1,4‐bis‐(trimethylsilyl)‐1,4‐diaza‐2,5‐cyclohexadiene. This template‐ and catalyst‐free graphitization method is gram scalable and modular for making nanostructures with tuneable compositions. The annealed germanium‐graphitic nanocomposite has been tested as anode material in lithium‐ion batteries.