A novel core/shell cuprous oxide-based structure with improved microwave absorbing and antibacterial performance

The cuprous oxide-based (Cu2O@NiCo2O4/RGO) composites were fabricated using a simple approach to achieve superior microwave absorbing (MA) performance and long-term antibacterial activity. The minimum reflection loss (RL) value reached −51.56 dB with an efficient absorption bandwidth (EAB) of 6.64 GHz. The enhanced MA performance was mainly due to increased interfacial polarization, efficient multiple reflection and scattering, and dipole polarization. Finite element method simulations were adopted to validate the improved MA performance of NiCo2O4 achieved with Cu2O and RGO. Its outstanding long-term antibacterial activity against S. aureus and P. aeruginosa is based on the synergistic effect between the continuous release of copper ions and ROS generated by photocatalysis. Density functional theory simulations were used to analyze the regulation of the work function of Cu2O@NiCo2O4/RGO, demonstrating the putative mechanism of ROS production. The Cu2O@NiCo2O4/RGO material is a promising MA antifouling agent for marine. [Display omitted] •Hybrid composites were synthesized with Cu2O core and NiCo2O4/RGO shell by a two-step method.•Superior MA performances with RLmin of −51.56 dB and EAB of 6.64 GHz.•Its outstanding long-term antibacterial activity against S. aureus and P. aeruginosa.•Improved long-term antibacterial ability due to the photocatalysis, persistent release of Cu2+ and ROS action.