摘要： Owing to the tunable coordinated ligands in the covalently terminated (such as eH or other organic groups) group IV graphane analogues (GAs), i.e., silicane, germanane, stannanane, the electronic structures, stability and other related properties in these materials can be rationally tuned. In this work, the methyl-terminated germanane GeCH3, synthesized through a solvothermal process by using the Zintl phase CaGe2 crystal as precursors, is reported as a new class of covalently terminated photocatalyst. In contrast to the H-terminated germanane GeH, the GeCH3 photocatalyst shows enhanced photocatalytic performance during both hydrogen generation and the decomposition of Rhodamine B (RhB) dye under visible light illumination (λ ≥ 420 nm). The higher photocatalytic activity of GeCH3 can be attributed to its higher surface area, lower charge transfer resistance and preferable electronic structures comparing to GeH with H termination. Our work indicates 2D GAs could be an attractive platform for high e?cient photocatalysts with tunable properties, which could be potentially applied in many ?elds.