Highly selective synthesis of multicarbon compounds by carbon dioxide hydrogenation over Pt nanocrystals anchoring Ru clusters

Abstract

Selective conversion of CO₂ to multicarbon compounds at low temperatures is a promising and challenging way to synthesize valuable chemicals and energy carriers by consuming CO₂. However, C–C coupling possesses high energy barriers over usual catalysts, resulting in low selectivities for multicarbon compounds. Small Ru clusters anchored on Pt nanoclusters (Ru-co-Pt) on carbon were prepared for the first time in this work which could catalyze CO₂ hydrogenation to form C₁–C₂₂ compounds at 130 °C with a C₂₊ selectivity of 90.1%, much higher than the values ever reported. It was found that Ru-co-Pt exhibited a much lower energy barrier for CH₂ + CH₂ coupling compared to Ru or Pt nanoclusters, and those for CH₂ or CH₃ hydrogenation. This new knowledge well accounts for the obtained high C₂₊ selectivity and provides a realistic strategy for developing advanced catalysts for synthesizing multicarbon hydrocarbons and alcohols and decreasing methane formation in CO₂ hydrogenation.