Optimizing Oxygen and Intermediate HOO<sup>*</sup> Adsorption of Cu–Pd Alloy Cocatalyst for Boosting Photocatalytic H<sub>2</sub>O<sub>2</sub> Production of BiVO<sub>4</sub>
Kaiyan Wang, Yang Li, Haiyang Shi, Feng Chen, Ping Wang, Xuefei Wang
Abstract
Abstract The modification of Pd cocatalysts is considered to be an effective strategy to improve H 2 O 2 production of photocatalysts because it can accelerate the reaction rate of O 2 reduction. However, the strong adsorption between O 2 molecules and Pd atoms is not conducive to the formation of intermediate HOO * and leads to the further reduction of H 2 O 2 to H 2 O, thus limiting the improvement of H 2 O 2 production. To solve the issue, in this work, Cu–Pd alloy cocatalysts are selectively modified on the electron‐rich facets of BiVO 4 via facile photoinduced deposition and subsequent galvanic displacement. DFT calculations indicate that the incorporation of Cu atoms to Pd atoms weakens the oxygen adsorption energy and HOO * binding energy on Pd atom surfaces, thus increasing the activity and selectivity of O 2 reduction to H 2 O 2 . Further experimental results show that the optimized Cu‐Pd/BiVO 4 (5:1) photocatalyst exhibits markedly boosted activity for H 2 O 2 production (2189 µ mol L ‐1 ), which is 3.2‐fold higher than that of BiVO 4 with modification of 0.3 wt% Pd cocatalyst (675 µ mol L ‐1 ). Additionally, the incorporation of metal Cu enables the economic utilization of Pd atoms and reduces the expense of the Pd cocatalyst.