Uniform CdS coated AuAg alloyed double-walled nanotubes were successfully fabricated by solvothermal process using Ag nanowires as the template. UV-vis-NIR extinction spectra revealed that the obtained double-walled nanotubes can present an enhanced light absorption ability compared with both pure AuAg alloyed nanotubes and CdS nanowires. Photocurrent and electrochemical impedance spectroscopy measurements indicated that such double-walled structure could significantly extend the lifetime of photo-generated carriers and increase the light-harvesting efficiency of CdS, due to the low charge transfer resistance and a high carrier transfer rate of the double-walled structure. The growth mechanism of such kind of nanotubes was also proposed. (C) 2017 Elsevier B.V. All rights reserved.