Efficient piezo-photocatalytic hydrogen evolution and hydrogen peroxide production: Z-type MoSe2/Bi0.5Na0.5TiO3 bifunctional heterojunction

Water splitting to produce H 2 and oxygen reduction to synthesize H 2 O 2 have become an effective strategy to meet energy needs due to their sustainability. However, simultaneous production of H 2 O 2 and H 2 in a catalytic system is still challenging. Herein, we constructed a novel MoSe 2 /Bi 0.5 Na 0.5 TiO 3 (MS/BNT) Z-type heterojunction as a piezo-photocatalyst for hydrogen and hydrogen peroxide production. Under the condition of piezoelectric photocatalysis, the optimized 5% MS/BNT catalyst achieved significant double high activity: the hydrogen evolution (HER) rate was as high as 3365.94 μmol/g/h, and the H 2 O 2 yield was 2784.5 μmol/g/h, which was 28 times and 14.7 times that of pure BNT, respectively. This excellent bifunctional catalytic performance is due to the synergistic effect of Z-scheme heterojunction and piezoelectric field, which effectively promotes the spatial separation of electron-hole pairs, thus greatly improving the simultaneous generation efficiency of H 2 and H 2 O 2 . This study provides a key new idea for the design of piezoelectric photocatalysts that can efficiently and synergistically produce a variety of high-value products (such as H 2 and H 2 O 2 ).