Engineering robust ZnO/Au decorated biomass-derived carbonaceous platforms for integrated antibacterial and electromagnetic wave absorbing properties

In consideration of the issues of electromagnetic pollution in medical settings, the function integration of high antibacterial activity and efficient wave absorption is becoming the preferred solution. In this work, spinach-derived carbon coupled with antibacterial assembly of ZnO nanorods decorated by Au nanoparticles were fabricated to form a hierarchical nanocomposite (CS-ZnO/Au) to meet the dual demands. Such an active platform guaranteed a pronounced bactericidal performance upon visible light illumination. 99.9% of E. coli and 99.7% of S. aureus were effectively eradicated in a lean period of 30 min, which was attributed to that ZnO/Au nanohybrids promoted the production of reactive oxygen species (ROS) and inhibited the charge recombination. Meanwhile, the anticipated wave attenuation ability was available owing to the multiple loss responses in the hierarchical CS-ZnO/Au. The ternary nanocomposites achieved the maximum absorbing bandwidth of 4.8 GHz and the strongest absorption of −54.61 dB. The mechanisms for wave absorption were ascribed to the improved dielectric loss and optimized impedance matching performance. It proposed an engineering robust platform, in sum, to tackle the dual challenges of antibacterial and wave absorption with these sustainable materials obtained from a green route.