Micro-Nanoarchitectonics of Electroless Cu/Ni Composite Materials Based on Wood

The changes of properties of wood-based Cu–Ni composites were studied via a simple electroless Cu and Ni method on wood surface to obtain Cu–Ni multilayer composites with excellent properties. The results showed that the wood was conducted via two times electroless Cu and one times electroless Ni had better performance, obtaining good surface roughness (9.99 μm) and good hydrophobic performance (contact angle, 122.5°). Here, Cu particles grew closely among Ni particles and embedded in Ni particles. The electrical conductivity of wood-based Cu–Ni composites was 2370.76 S/cm. When the electroless Ni was 55 min, the contact angle could reach 123°, indicating that the composite coatings had best hydrophobicity. The Ni/Cu, Cu/Cu, and Cu/Wood three layers with different electrical-magnetic properties can induce multiple reflections at each interface, which promote to the absorption attenuation. The average electromagnetic shielding effectiveness of Cu and Ni wood-based composites can reach 93.8 dB at L band ranging from 0.3 × 10−3 to 3.0 × 103 MHz with a low thickness (157 μm) and an ultralow density (0.75 g/cm3), verified the multilayer composite materials can block over 99.99% of incident EM waves.