Synthesis of Low-Carbon Alcohols from Syngas over Cu–Fe/TiO ₂ Catalysts with an Anatase–Rutile Junction

The use of anatase–rutile mixed-phase TiO 2 (P25) as a support improves both CO conversion and selectivity toward low-carbon alcohols (C 1 –C 5 mixed alcohols) during syngas conversion over Cu–Fe bimetallic catalysts. A 61.4% selectivity to low-carbon alcohols was obtained at a CO conversion of 35.0%. The low-carbon alcohol yield (21.5%) over CuFe/P25 is 31 and 3 times higher than the yields over Cu–Fe catalysts supported on pure anatase TiO 2 and pure rutile TiO 2, respectively. The anatase–rutile synergy in P25 contributes to the high dispersion of Cu–Fe species and facilitates electron transfer from the P25 support to both Cu 0 and FeC x active sites via metal–support interaction. CuFe/P25 enhances both the capabilities of CO adsorption, dissociation, and non-dissociative insertion and the formation of CH x, CHO, and HCOO intermediates. These findings suggest that tuning the crystalline phase of the support constitutes a rational strategy for enhancing the catalytic activity of the metal sites.