Insights into the Activity Screening and Hydroformylation Kinetics of Rh-Based Bimetallic Phosphides

Heterogeneous hydroformylation is of great industrial and economic interest. Here, we proposed a screening strategy to search highly active Rh-based bimetallic phosphide catalysts and successfully predicted Rh7Pd1P4 as a new active site, which was more active than other phosphide catalysts. Experimental verifications confirmed the synthesis of bimetallic phosphides and the activity enhancement for styrene hydroformylation. The kinetics of styrene hydroformylation was studied based on the rate-determining step (RDS) achieved from density functional theory (DFT) calculations. The proposed two-parameter kinetics was more consistent with the experimental data than previously used first-order or zero-order models. By changing the reaction pressure, the RDS could be identified by experiments with the help of the kinetic model. The RDS identified from the experiments and the kinetic model agreed well with the DFT calculations, which further proved the accuracy of the kinetic model.