Fabrication and characterization of bio-based shielding material with dissimilar surface resistivity prepared by electroless Ni-Fe-P alloy plating on bamboo (N. affinis)

To deal with the electromagnetic radiation, a bio-based shielding material with dissimilar surface resistivity was fabricated by electroless Ni-Fe-P plating on bamboo surface. The effects of plating parameters, such as pH, main salt mole ratio, etc. on the deposition rate, resistivity, and chemical composition of the coating were investigated. The SEM, EDS, XRD, and XPS were used to study the surface morphologies, chemical composition, and crystal structures of the optimal coating. Besides, the results of electrical conductivity, magnetism, and shielding effectiveness (SE) showed the bamboo was endowed with good conductivity, magnetism, and SE after plating. Thereinto, the SE of plated bamboo was higher than 55 dB (0.1 MHz-2.0 GHz), which far surpassed the targeted value of 20 dB for commercial applications. Additionally, the corrosion property and thermal stability of material were also concerned. The TGA results displays the thermal stability of Ni-Fe-P-coated bamboo was enhanced compared with raw bamboo. Moreover, we found the alloy was not simply surface-coated but permeated into bamboo because of its porosity. Furthermore, an interesting phenomenon has been found for the first time: the Ni-Fe-P-coated bamboo has the characteristic of surface resistivity dissimilarity which could be reflected in different structures, different planes, and different locations.