Monday, 30 May 2022: 11:00
West Meeting Room 113 (Vancouver Convention Center)
In this study, we synthesized Zn2SnO4 (ZTO) nanowires with an aspect ratio greater than 100 in a three-zone furnace tube through chemical vapor deposition and selective etching. Chemical bath redox method was used to modify different percentages of Ag nanoparticles on the ZTO nanowires and explore the change of photocatalytic properties of ZTO NWs after modification. With optical properties detected by PL and UV-Vis, the photoluminescence spectrum of ZTO nanowires was mainly in the visible light region, and attributed to oxygen vacancies. The luminescence intensity of the nanowires was significantly reduced after modification, proving that the heterogeneous junction can effectively reduce the electron-hole pairs recombination, and the reduction increased with the increase of the Ag NPs modification. The conversion from UV-Vis absorption spectrum to Tauc Plot shows that the band gap of the nanowire is 4.05eV, and it would not change apparently after modification. The single ZTO NW revealed low electrical resistivity of 6.01*10-5 Ω·m. With 10ppm methylene blue as the degradation solution, ZTO nanowires was degraded 85% after 120 minutes, 1% Ag-ZTO was degraded 94% after 120 minutes, and 3% Ag-ZTO was degraded 96% after 120 minutes. The nanowires maintained an excellent photodegradation rate after three cycles of degradation. The main mechanism of the reaction was confirmed by photocatalytic inhibitors; the degradation rate was reduced from 96% to 15% with the inhibition of h+, while the degradation rate was reduced from 96% to 52% with the inhibition of ·OH. Consequently, h+ and ·OH were the main reactants of photodegradation.
Keywords: Zin-tin-oxide, nanowires, CVD, surface modification, photocatalysis