Solution-Chemical Route to Generalized Synthesis of Metal Germanate Nanowires with Room-Temperature, Light-Driven Hydrogenation Activity of CO_2 into Renewable Hydrocarbon Fuels

摘要

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/H_2O 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 Cd_2Ge_2O_6 nanowires were also successfully obtained through the addition of Co(OAc)_2·4H_2O to the initial reaction mixture for future investigation of the magnetic properties of these nanowires. The considerably negative conduction band level of the Cd_2Ge_2O_6 nanowire offers a high driving force for photogenerated electron transfer to CO_2 under UV?vis illumination, which facilitates CO_2 photocatalytic reduction to a renewable hydrocarbon fuel in the presence of water vapor at room temperature.