Effect of CuSO4 Content in the Plating Bath on the Properties of Composites from Electroless Plating of Ni-Cu-P on Birch Veneer

Abstract

A wood-based composite was prepared via simple electroless Ni-Cu-P plating on birch veneer for EMI shielding. The effects of CuSO 4 ·5H 2 O concentration on the metal deposition, elemental composition, phase structure, surface morphology, wettability, surface resistivity, and shielding effectiveness of coatings were investigated. The coatings were characterized using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). When the CuSO 4 ·5H 2 O concentration was increased from 0.6 g/L to 2.2 g/L, the metal deposition was decreased from 79.61 g/m 2 to 66.44 g/m 2 . Elemental composition showed that the copper content in the coating increased significantly, whereas the nickel content was reduced significantly and the phosphorus content was slightly reduced. The crystallinity of coatings increased, and fine-grain structure was observed, with higher copper content. Ni-Cu-P deposition improved the hydrophobic properties when the maximum static contact angle increased from 77.5° to 116.5°. The lowest surface resistivity was 367.5 mΩ/cm 2 , and the EMI shielding effectiveness of Ni-Cu-P-coated veneers was higher than 60 dB in frequencies ranging from 9 kHz to 1.5 GHz.

Studies on electroless nickel polyalloy coatings over carbon fibers/CFRP composites

“…Guangyu Li et al [24] and Hui et al [18] in their studies on electroless coatings over CF/PEEK and Birch veneer respectively had observed a decrease of SE with increasing copper content.…”

“…10 dB [18]. From the scattering parameters, the EMI SE is calculated from the equations given below:…”

Fabrication of flexible thin veneer for electromagnetic interference shielding and decoration through simple electroless plating

“…Therefore, as early as 20 years ago, electroless plating technology was used to prepare electromagnetic shielding wood (Nagasawa et al 1999;Wang et al , 2006; . In the following ten years, the form of wood electromagnetic shielding materials has also been expanded, such as electromagnetic shielding particle board and plywood Hui et al 2013Hui et al , 2014Pan et al 2016;Tang et al 2016).…”

On the kinetics of copper electroless plating with hypophosphite reductant

“…3,4 The physicochemical characteristics of autocatalytic deposits are closely dependent on the composition of the baths and the respective operating conditions. [5][6] Hence, the interest of research performed about the kinetic phenomena arising at the metal/solution interface. [7][8][9] Most of commercially electroless copper baths use (i) formaldehyde, 10 as the reducing agent; (ii) sodium potassium tartrate (called as 'Rochelle salt'), sodium citrate or ethylenediamine tetraacetic acid, as complexing agents; (iii) boric acid as a buffer; (iv) oxygen or thiourea, as additives for stabilising the system; and (vi) cyanide or proprionitrille, as additives for accelerating the reaction.…”

“…3,4 The physicochemical characteristics of autocatalytic deposits are closely dependent on the composition of the baths and the respective operating conditions. 5–6 Hence, the interest of research performed about the kinetic phenomena arising at the metal/solution interface. 7–9…”