In Situ Selenization Induced Electron‐Rich Pd with Weakened O2 Adsorption for Boosted Photocatalytic H2O2 Production

Abstract Pd cocatalysts show great potential for the photocatalytic production of H 2 O 2 . However, the catalytic efficiency of Pd cocatalyst is limited due to the strong adsorption of O 2 , which promotes O−O bond cleavage and thus reduces selectivity for the two‐electron O 2 reduction reaction. Considering that adjusting the electron density of Pd can predominately optimize Pd−Oads bond strength, in this work, electron‐rich Pd sites are constructed by introducing Bi 2 Se 3 middle layer between Pd cocatalysts and (010) facet of BiVO 4 using an in‐situ selenization strategy. The photocatalytic results indicate that the designed BiVO 4 /Bi 2 Se 3 −Pd(0.3 %) photocatalyst achieves a high H 2 O 2 yield of 2166 μmol L −1 in 2 h, which is 36 times and 3.75 times higher than BiVO 4 /Bi 2 Se 3 and BiVO 4 /Pd photocatalyst, respectively. Additionally, the corresponding AQE value of BiVO 4 /Bi 2 Se 3 −Pd is 6.71 %. The subsequent Density functional theory (DFT) calculations and XPS spectra confirm that the introduction of Bi 2 Se 3 via in‐situ selenization increases the electron density of Pd. This enhances the formation of electron‐rich Pd sites, reduces O 2 adsorption, and ultimately improves the photocatalytic H 2 O 2 yield. This strategy provides insights into designing efficient photocatalysts for H 2 O 2 production through electronic structure modulation.