Preceding electroless plating, the substrates were activated
with Pd nuclei via sensitisation in an acidic SnCl2 solution,
followed by activation in an acidic PdCl2 solution.
The sensitisation/ activation process was carried out by immersing the
glazed hollow fibre substrates sequentially in five chemical
baths, i.e. acidic SnCl2 solution for 5 min; deionised water for
5 min, acidic PdCl2 solution for 5 min; 0.01 M HCl solution for
2 min; and finally deionised water for 3 min.
All chemical baths were homogenised by air bubbles. The sensitisation/
activation process was repeated for 8 cycles.
The composition of each bath is presented in Table 1.