ofCuO–ZnO–Al2O3deposited on Al2O3-modified H-ferrierite was investigated to elucidate effects of Al2O3modification of H-ferrierite in terms of CO conversion and DME yield. The enhanced catalytic activity wasobserved on the bifunctional catalysts at an optimum content of Al2O3on H-ferrierite around 2.5–5 wt%.It is attributed to a higher dispersion of Al2O3on H-ferrierite with an enhanced interaction of copperparticles with Al2O3modified H-ferrierite with a lower aggregation property by adjusting acidic sitesand by increasing the dispersion of copper particles. The main role of Al2O3on H-ferrierite is found toreduce strong acidic sites by depositing on the sites selectively, which resulted in showing a lower for-mation of byproducts. Both of copper surface area and amount of acidic sites are well correlated with anintrinsic activity (turn-over frequency; TOF), which revealed a structure-insensitive reaction character ofa single-step synthesis of DME. The measurements of the dispersion of Al2O3and copper particles withthe number of acidic sites concomitantly were employed to verify the effects of Al2O3modification ofH-ferrierite though X-ray photoelectron spectroscopy, temperature-programmed methods and surfacemorphology characterizations.© 2013 Elsevier B.V. All rights reserved.