▎ 摘　　要

NOVELTY - Methyl substituted germanane-reduction-oxidation graphene (GeCH3-RGO-SP) nanocomposite lithium ion battery negative electrode material comprises reduced graphene oxide and conductive carbon black. The conductive carbon black wraps the methyl substituted germanane nano sheet to form three-dimensional conductive network and ion transport channel. The preparation includes weighing calcium and germanium, mixing, placing in quartz glass tube, heating, cooling to obtain calcium-gemanium (CaGe2) crystal, mixing CaGe2 crystal, water and acetonitrile, adding iodomethane, mixing at room temperature in water bath, dispersing samples of GeCH3, reduced graphene oxide and conductive carbon black in isopropanol to obtain mixture of GeCH3-reduced graphene oxide-conductive carbon black-isopropanol and drying. USE - Methyl substituted germanane-reduction-oxidation graphene nanocomposite lithium ion battery negative electrode material. ADVANTAGE - The material increases specific surface area of materials, slows down the volume expansion of germanium based materials, provides more diffusion channels for lithium ions, enhances electronic conductivity of the whole materials and can charge and discharge up to 1000 times in a long cycle at a high rate. DETAILED DESCRIPTION - Methyl substituted germanane-reduction-oxidation graphene (GeCH3-RGO-SP) nanocomposite lithium ion battery negative electrode material comprises reduced graphene oxide and conductive carbon black. The conductive carbon black wraps the methyl substituted germanane nano sheet to form three-dimensional conductive network and ion transport channel. The preparation comprises weighing calcium and germanium at molar ratio of 1:2, mixing, placing in quartz glass tube, using inert protective gas to exhaust oxygen, using vacuum sealing system to perform vacuum, heating tube furnace at 900-1000 degrees C for 16-24 hours, cooling to 850-860 degrees C at 0.1-0.5 degrees C per minute, 800-830 degrees C at 0.01-0.03 degrees C per minute, 700-730 degrees C at 0.1-0.5 degrees C per minute and 20-25 degrees C at 1-5 degrees C per minute to obtain calcium-gemanium (CaGe2) crystal, mixing CaGe2 crystal, water and acetonitrile, adding iodomethane, mixing at room temperature in water bath, dispersing samples of GeCH3, reduced graphene oxide and conductive carbon black in isopropanol to obtain mixture of GeCH3-reduced graphene oxide-conductive carbon black-isopropanol and drying in vacuum at room temperature. The molar ratio of CaGe2 crystal, water and iodomethane is 1:6-10:20-30. The amount of acetonitrile is 16-22 ml for every 0.1 g CaGe2 crystal. The mass ratio reduced graphene oxide and conductive carbon black is 1-5:1.