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Rational modulation of metal−support interaction is an effective strategy to enhance the catalytic performance of a supported catalyst. Here, both the activity and selectivity for the direct H 2 O 2 synthesis from H 2 and O 2 are enhanced by the doping of boron atoms at the interface of Pd and TiO 2 . With boron doping, the selectivity and productivity of H 2 O 2 are remarkedly increased from 63.4% and 2.99 mol H 2 O 2 g Pd −1 h −1 to 80.1% and 3.65 mol H 2 O 2 g Pd −1 h −1 in a triphase semicontinuous reaction system at 10 °C and 0.1 MPa, respectively. The modulation effect of boron on the structure of Pd/TiO 2 was thoroughly studied by using multiple techniques such as HRTEM, XRD, XPS, and in situ DRIFTS. The doped boron atom almost has no effect on the particle size of Pd nanoparticle, but enhances the strong metal− support interaction (SMSI) between the Pd particle and TiO 2 , which results in a change of the Pd 2+ /Pd 0 ratio and surface Pd atoms configuration. An appropriate amount of boron atoms doped at the Pd−TiO 2 interface increases the ratio of Pd 2+ species, providing more active sites for the nondissociative activation of O 2 . Furthermore, the electronic effect between boron and Pd species increases the H 2 adsorption and activation, resulting in simultaneous increases in H 2 O 2 selectivity and productivity. This work highlights the significance of the modulation for metal−support interaction on direct H 2 O 2 synthesis, which also provides an effective and economic route by interface doping to improve the performance of supported heterogeneous catalysts.

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