Pair-Site Rh-WOx/SiO2 catalyst for hydroformylation of isobutene: An interface electronic regulation strategy to enhance catalytic efficiency

Hydroformylation plays a crucial role in the modern chemical industry by enabling the efficient production of aldehydes, which are essential raw materials for a wide range of chemicals. In this study, we reported a pair-site 0.2Rh-0.8WO x /SiO 2 catalyst that demonstrated exceptional performance in isobutene hydroformylation. The catalyst achieved an isovaleraldehyde yield of 89.57 % (TON=8936) after 5 h of reaction at 90 °C and 5 MPa, and retained 85.0 % of its initial yield after four cycles. This performance was significantly superior to that of the catalyst prior to the introduction of W and proved more suitable for the hydroformylation reaction of isobutene compared to previously reported Al 2 O 3 -supported pair-site catalyst. Density functional theory (DFT) calculations revealed that W served as an electronic modulator in the catalytic system. The charge transfer from Rh to W enabled W to adsorb and convert excess CO on the Rh surface, thereby creating vacant active sites for the subsequent insertion of olefin and CO, ultimately enhancing the hydroformylation performance. The pair-site catalyst developed in this study exhibited remarkable improvements in both catalytic activity and stability, offering valuable guidance for catalyst design from an interface science perspective.