Integration of interface engineering and La doping to boost two‐electron oxygen reduction to hydrogen peroxide over La ₂ Sn ₂ O ₇ @La‐doped ZnSnO ₃ heterostructures

Abstract Perovskite oxides have shown great potential application in fuel cells due to the unique crystal structures and tunable composition as well as effective capability toward the oxygen reduction reaction (ORR), whereas the investigation on the electrocatalytic performance of perovskite oxides toward the two‐electron ORR to H 2 O 2 production remains very limited. Herein, a facile synthetic method has been developed to prepare La 2 Sn 2 O 7 @La‐doped ZnSnO 3 heterostructures comprising of amorphous La 2 Sn 2 O 7 and crystalline La‐doped ZnSnO 3 . The optimal La 2 Sn 2 O 7 @La‐doped ZnSnO 3 heterostructures catalyst exhibits a significantly improved two‐electron ORR performance to H 2 O 2 production with onset potential of 0.77 V and large current density of 2.51 mA·cm −2 at 0.1 V compared to ZnSnO 3 (0.75 V, 1.80 mA·cm −2 , 0.11 mA) as well as maintains high H 2 O 2 selectivity of 80%, which has been theoretically demonstrated to be contributed to the synergistic effect of amorphous La 2 Sn 2 O 7 and crystalline La‐doped ZnSnO 3 . Moreover, high H 2 O 2 yield rate of 2.9 mM·h −1 at 0.1 V can be achieved with a superior turnover frequency (TOF) of 3.31 × 10 −2 s −1 compared to the ZnSnO 3 catalyst (2.10 × 10 −2 s −1 ). This work reveals the great potential of perovskite oxide as promising candidates for the environmentally friendly synthesis of hydrogen peroxide.