Synthesis of PbS quantum dots/ZnO nanorods/Ag nanowires composite photocatalysts with enhanced photocatalytic activity

• Published in: Materials letters Vol. 285; p. 129130
• Main Authors: Wei, Junwei, Wei, Shuoming, Chang, Na, Wang, Haitao, Zhang, Jimei, Shao, Wei
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.02.2021; Elsevier BV
• Subjects: Ag NWs; Catalytic activity; Electron paramagnetic resonance; Electron spin; Materials science; Methylene blue; Nanorods; Nanowires; PbS QDs; PbS QDs/ZnO NRs/Ag NWs composite; Performance degradation; Photocatalysis; Photocatalysts; Photocatalytic performance; Photodegradation; Quantum dots; Silver; Spin resonance; Zinc oxide; ZnO NRs; PbS QDs/ZnO NRs/Ag NWs composite; ZnO NRs; Ag NWs; Photocatalytic performance; PbS QDs
• ISSN: 0167-577X; 1873-4979
• DOI: 10.1016/j.matlet.2020.129130

•Ag nanowires were selected to capture photogenerated electrons.•ZnO nanorods were planted on Ag nanowires.•PbS quantum dots as the shell of the catalytic system.•The composite exhibits high catalytic performance in the degradation of MB. In this work, PbS quantum dots/ZnO nanorods/silver nanowires (PbS QDs/ZnO NRs/Ag NWs) composite photocatalysts were successfully synthesized. The amount of PbS QDs was controlled by the number of successive ionic layer adsorption and reaction (SILAR) cycles. The cycle was repeated 5, 9 and 13 times, respectively. Degradation of methylene blue under simulated sunlight conditions to evaluate the photocatalytic activity of materials. As expected, the PbS QDs/ZnO NRs/Ag NWs composite performs enhanced photocatalytic activity compared to ZnO NRs and ZnO NRs/Ag NWs. In addition, the experimental results show SILAR cycles have a significant effect on the loading of PbS QDs on ZnO NRs and photocatalytic activity of the composite, among different composites, the composite with 9 SILAR cycles shows the best photocatalytic performance in the degradation of methylene blue (MB). MB can be almost completely degraded in 30 min. The radical-trapping experiments and electron spin resonance demonstrate that superoxide anion radicals and photogenerated holes are main reactive species for photocatalytic degradation.