A series of FeOx-promoted Ir/BN catalysts were tested for gas phase selective hydrogenation of crotonaldehyde. The addition of FeOx in the catalyst greatly improves the performance, up to a 5-fold enhanced steady state crotyl alcohol yield (46.9%) compared to that of the bare Ir/BN (7.2%). The characterization results reveal that the Ir-FeOx interaction results in the generation of new active sites at the interface, which are responsible for the enhanced performance. The kinetic study showed that the Ir-FeOx interfacial active site has much higher turnover frequency (82.9 x 10(-3) s(-1)) than the Ir-0-Ir8+ site in the Ir/BN catalyst (3.10 x 10(-3) s(-1)), due to the promotion of FeOx leads to a higher intrinsic rate constant (12.1 x 10(-7) v.s. 1.19 x 10(-7) mol g(-1) s(-1)) and a higher adsorption equilibrium constant of crotonaldehyde (3.49 v.s. 0.62 kPa(-1)).