NiCu single atom alloy (SAA) nanoparticles supported on silica are reported to catalyze the non-oxidative dehydrogenation of ethanol, selectively to acetaldehyde and hydrogen products by facilitating the CH bond cleavage. The activity and selectivity of the NiCu SAA catalysts were compared to monometallic copper and to PtCu and PdCu single atom alloys, in a flow reactor at moderate temperatures. In-situ DRIFTS showed that the silica support facilitates the OH bond cleavage of ethanol to form ethoxy intermediates over all the supported alloy catalysts. However, these remain unreactive up to 250 °C for the Cu/SiO₂ monometallic nanoparticles, while in the NiCu SAA, acetaldehyde is formed at much lower temperatures, below 150 °C. In situ DRIFTS was also used to identify the CH activation step as the rate determining step of this reaction on all the copper catalysts we examined. The presence of atomically dispersed Ni in Cu significantly lowers the CH bond activation barrier, whereas Pt and Pd atoms were found less effective. This work provides direct evidence that the CH bond cleavage is the rate determining step in ethanol dehydrogenation over this type catalyst.

据报道，负载在二氧化硅上的NiCu单原子合金（SAA）纳米颗粒可通过促进C H键裂解，催化乙醇的非氧化脱氢，选择性地转化为乙醛和氢产物。在适度的温度下，将NiCu SAA催化剂的活性和选择性与单金属铜以及PtCu和PdCu单原子合金进行了比较。原位DRIFTS表明，二氧化硅载体可促进乙醇的O H键裂解，从而在所有负载的合金催化剂上形成乙氧基中间体。但是，对于Cu / SiO ₂单金属纳米粒子，这些物质在高达250°C的温度下仍然不反应，而在NiCu SAA中，乙醛是在低于150°C的低得多的温度下形成的。原位DRIFTS还用于确定C H活化步骤，作为我们检测的所有铜催化剂上该反应的速率确定步骤。Cu中原子分散的Ni的存在显着降低了C H键的活化势垒，而Pt和Pd原子的有效性较低。这项工作提供了直接的证据，证明C H键的裂解是该类型催化剂上乙醇脱氢的速率决定步骤。