Multi-core@Shell catalyst derived from LDH@SiO2 for low- temperature dry reforming of methane

In this paper, a multi-core@shell catalyst LDH@SiO2 was fabricated by coating a silica layer over hexagonal Ni–Mg–Al LDH nanoplates. After calcination and H2-reduction, Ni nanoparticles were well dispersed on the support, as well as encapsulated within the mesoporous silica shell. The multi-core@shell catalyst was then tested in low temperature dry reforming of methane (DRM) at 600 °C and showed a stable CH4 conversion of 27% for 16 h time on stream. Characterizations of the spent catalyst indicated that there was almost no carbon formation and the multi-core@shell structure was well preserved. While the pristine layered double hydroxide (LDH) catalyst exhibited a severe carbon formation as 68%. The confinement effect conveyed by the unique multi-core@shell structure effectively suppressed metal sintering and carbon deposition. Besides, the thickness of the silica shell was tuned and it made a great difference to the catalytic activity due to the diffusion resistance.