Suitable supports for NiO species and NiO-support synthesis are important in CO methanation. We have used expanded multilayered vermiculite (VMT) as catalyst support and synthesized NiO/VMT composite by microwave irradiation-assisted synthesis (MIAS). Compared with conversional heat treatment (i.e., 550 degrees C for 4 h), the MIAS method provides rapid heating of the Ni/VMT precursor (i.e., 700 W for 4 min), which results in a Ni/VMT catalyst with highly dispersed active sites. The Ni/VMT(MIAS) exhibits excellent catalysis performance, including a high 99.6% CO conversion, 93.8% CH4 selectivity, and turn over frequency of 5.88 x 10(-4) s(-1), at 400 degrees C, an gas hourly space velocity of 12,000 h(-1), a synthesis gas flow rate of 65 mL min(-1) and a pressure of 1.5 MPa. The design and fabrication of Ni/VMT(MIAS) may promote the synthesis of VMT-based catalysts with better CO methanation performance based on its outstanding structure and allow for its applications in other areas. (C) 2016 Elsevier Ltd. All rights reserved.