Ultrafast and Robust UV Luminescence from Cu-Doped ZnO Nanowires Mediated by Plasmonic Hot Electrons

Leveraging on plasmonic hot electrons is regarded as an emerging strategy for electron-hole separation toward effi cient photovoltaics and photocatalysis, but its application in electron-hole recombination for illumination is rarely explored. Herein, a signifi cantly improved ultraviolet luminescence is reported from Cu-doped ZnO nanowires (NWs) through dopant mediated generation and transfer of plasmonic hot electrons. Through coupling the Cu dopants-correlated green luminescence in Cu-doped ZnO NWs with the localized surface plasmon resonance of Au nanoparticles (NPs), UV emission from the NWs is enhanced by a factor of approximate to 280 and its lifetime drops from 2.45 ns to about 18 ps after covering the NWs with Au NPs. Moreover, robust UV emission sustains from room temperature to low temperature. This work extends the applications of plasmonic hot electrons and provides an appealing route toward achieving intense, ultrafast, and temperature-robust luminescence, which holds great potential in light-emitting diode and laser diodes for illumination, optical communication, and biomedical applications.