Tunable plasmonic resonance induced by the collective oscillation of the electrons on metallic nanostructures can excellently enhance the light response of ZnO films, which provides an effective way to break through the limitation of the performance of ZnO photodetectors. Here, broad-band high-performance ZnO/Au heterostructures photodetectors with various morphologies of self-assembled Au nanoantennas are fabricated via a facile approach under the spin-coated ZnO colloidal quantum dots films. With a systematic control on growth condition, the self-assembled Au nanoantennas undergo a drastic evolution from the corrugated nanomounds to the island-like nanostructures, and the light absorption of the resulting ZnO/Au heterostructures correspondingly exhibits a strongly morphological dependence on the Au nanoantennas. Meanwhile, the photoresponse of the ZnO-based photodetectors is significantly improved throughout a wide spectrum between UV and visible regions owing to the enhanced light absorption induced by the localized surface plasmon resonance. As a result, the optimal switch ratio of the ZnO/Au heterostructures photodetector increases by 1 order to ∼1.13 × 10 than that of the pristine ZnO one because of the obviously increased photocurrent ( I) and comparable dark current, thus leading to ∼9.1 and ∼4.9 times increases in the photoresponsivity and the normalized detectivity. Meanwhile, the significant increases in the I of ∼5.2 and ∼9.7 times are likewise observed with the ZnO/Au heterostructures under 530 nm and white-light illumination. This work can offer a handy and effective approach for the fabrication of ultrasensitive ZnO-based photodetectors within a broad-band wavelength by utilizing the Au plasmonic nanostructures.

Background: Since December 2019, the cumulative number of coronavirus disease 2019 (COVID-19) deaths worldwide has reached 1,013,100 and continues to increase as of writing. Of these deaths, more than 90% are people aged 60 and older. Therefore, there is a need for an easy-to-use clinically predictive tool for predicting mortality risk in older individuals with COVID-19. Objective: To explore an easy-to-use clinically predictive tool that may be utilized in predicting mortality risk in older patients with COVID-19. Methods: A retrospective analysis of 118 older patients with COVID-19 admitted to the

Microwave-absorbing materials have attracted enormous attention for electromagnetic (EM) pollution. Herein, hollow beaded Fe3C/N-doped carbon fibers (Fe3C/NCFs) were synthesized through convenient electrospinning and subsequent thermal treatment. The special hollow morphology of the samples is conducive to achieve lightweight and broadband microwave absorption properties. The thermal treatment temperatures exhibit a significant impact on conductivity and EM properties. The broadest effective absorption bandwidth (EAB) is 5.28 GHz at 2.16 mm when the thermal treatment temperature is 700 °C, and the EAB can cover 13.13 GHz with a tunable absorber thickness from 1.0 to 3.5 mm when the thermal treatment temperature is 750 °C. The excellent microwave absorption properties of the samples are due to the synergistic effect of impedance matching and strong EM energy attenuation abilities. Hence, the magnetic hollow beaded Fe3C/NCFs are expected to be an attractive candidate material as a lightweight and efficient microwave absorber in the future.

HIGHLIGHTS• High performance Al nanostructures/ZnO quantum dots heterostructure photodetectors with a controllable geometry of the Al nanostructures are demonstrated.• Light utilization of the photoactive layers is significantly boosted with the Al nanostructures.• The light confinement effect is inherently determined by the geometries of the Al nanostructures.