A supported mixed-conducting LNCO membrane with a pore-gradient structure LNO support was successfully prepared via a dry pressing and co-sintering route. The match of sintering behaviors between membrane and support was realized by the preparation of an ABB'B '' B'BA-type membrane. A scanning electron microscopy (SEM) test demonstrated that the surface of the supported membrane was dense and crack-free and the pore-gradient structure of the support can be observed clearly. The oxygen flux of the supported membrane was about 5.6 times that of the symmetric LNCO membrane. A self-catalytic mixed-conducting membrane reactor was constructed using the prepared membrane for hydrogen production from methane. It was found that this membrane reactor exhibited high performance and good stability for hydrogen production. At 1123 K. the CH4 conversion, hydrogen selectivity and hydrogen production remained at about 60%,89% and 8.0 ml(STP) cm(-2) min(-1), respectively, for more than 120 h. (C) 2008 Elsevier B.V. All rights reserved.