The effects of oxygen partial pressure and a Cu catalyst on the growth of Zn2GeO4 nanowires (NWs) on Si substrates by thermal evaporation of ZnS and Ge powders at 1000–1100°C in Ar were studied. The Zn2GeO4 NWs could grow on the bare Si substrates at 650–800°C in Ar, while a deposited Cu layer further enhanced their growth, forming the Cu-doped Zn2GeO4 NWs. The growth of both the Zn2GeO4 and Cu-doped Zn2GeO4 NWs followed the self-catalyzed vapor–liquid–solid process. In Ar/normalO2(3%) , GeO2 nanoparticles instead of Zn2GeO4 NWs predominantly formed on the Si substrates, revealing that the higher oxygen partial pressure in Ar enhanced the growth of GeO2 . The green emission peak of Cu-doped Zn2GeO4 NWs showed a blueshift of about 25 nm relative to that of the undoped Zn2GeO4 NWs.

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