In this study, a phase-inversion assisted co-extrusion/co-sintering technique has been employed to fabricate a triple-layer ceramic hollow fibre in one step for micro-tubular solid oxide fuel cells (SOFCs). The fibres developed consist of an exterior symmetric electrolyte layer (CGO), a symmetric anode functional layer (AFL, NiO(40 wt%)/CGO(60 wt%)) and an interior asymmetric anode layer (NiO(60 wt %)/CGO(40 wt%)) where radical finger-like voids provide lower fuel diffusion resistance. In addition to more triple-phase boundary (TPB) for electrochemical reactions, the AFL forms a graded porosity with better conductivity and sintering behaviours, leading to greater bounding characteristics between the electrolyte and anode. AFL between 19.1 and 77.5 mu m can be achieved by simply adjusting its extrusion rate during co-extrusion, with no cracks or delamination observed after co-sintering. Moreover, the effects of AFL thickness on physical and electrochemical properties of the obtained triple-layer s were investigated systematically using various characterisation techniques. The results illustrate that the AFL between anode and electrolyte improves the mechanical strength of the whole and gas-tightness of the electrolyte, despite for slight drops in electrical conductivity and average porosity of anode and AFL. (C)) 2013 Elsevier B.V. All rights reserved