Solution-Chemical Route to Generalized Synthesis of Metal Germanate Nanowires with Room-Temperature, Light-Driven Hydrogenation Activity of CO₂ into Renewable Hydrocarbon Fuels

A facile solution-chemical route was developed for the generalized preparation of a family of highly uniform metal germanate nanowires on a large scale. This route is based on the use of hydrazine monohydrate/H₂O as a mixed solvent under solvothermal conditions. Hydrazine has multiple effects on the generation of the nanowires: as an alkali solvent, a coordination agent, and crystal anisotropic growth director. Different-percentage cobalt-doped Cd₂Ge₂O₆ nanowires were also successfully obtained through the addition of Co­(OAc)₂·4H₂O to the initial reaction mixture for future investigation of the magnetic properties of these nanowires. The considerably negative conduction band level of the Cd₂Ge₂O₆ nanowire offers a high driving force for photogenerated electron transfer to CO₂ under UV–vis illumination, which facilitates CO₂ photocatalytic reduction to a renewable hydrocarbon fuel in the presence of water vapor at room temperature.