Frei Matthias S, Mondelli Cecilia, García-Muelas Rodrigo, Morales-Vidal Jordi, Philipp Michelle, Safonova Olga V, López Núria, Stewart Joseph A, Ferré Daniel Curulla, Pérez-Ramírez Javier
Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zürich, Zürich, Switzerland.
Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology, Tarragona, Spain.
Nat Commun. 2021 Mar 30;12(1):1960. doi: 10.1038/s41467-021-22224-x.
Metal promotion in heterogeneous catalysis requires nanoscale-precision architectures to attain maximized and durable benefits. Herein, we unravel the complex interplay between nanostructure and product selectivity of nickel-promoted InO in CO hydrogenation to methanol through in-depth characterization, theoretical simulations, and kinetic analyses. Up to 10 wt.% nickel, InNi patches are formed on the oxide surface, which cannot activate CO but boost methanol production supplying neutral hydrogen species. Since protons and hydrides generated on InO drive methanol synthesis rather than the reverse water-gas shift but radicals foster both reactions, nickel-lean catalysts featuring nanometric alloy layers provide a favorable balance between charged and neutral hydrogen species. For nickel contents >10 wt.%, extended InNi structures favor CO production and metallic nickel additionally present produces some methane. This study marks a step ahead towards green methanol synthesis and uncovers chemistry aspects of nickel that shall spark inspiration for other catalytic applications.
多相催化中的金属促进作用需要纳米级精确结构才能实现最大化和持久的效益。在此，我们通过深入表征、理论模拟和动力学分析，揭示了镍促进的InO在CO加氢制甲醇过程中纳米结构与产物选择性之间的复杂相互作用。镍含量高达10 wt.%时，在氧化物表面形成InNi斑块，其不能活化CO，但通过提供中性氢物种促进甲醇生成。由于InO上产生的质子和氢化物驱动甲醇合成而非逆水煤气变换反应，而自由基促进这两种反应，具有纳米合金层的贫镍催化剂在带电和中性氢物种之间提供了有利的平衡。对于镍含量>10 wt.%，扩展的InNi结构有利于CO生成，额外存在的金属镍会产生一些甲烷。这项研究朝着绿色甲醇合成迈出了一步，并揭示了镍的化学特性，这将为其他催化应用带来启发。
