Piezoelectric charges promote FeS2 regeneration for efficient catalytical seawater splitting H2 evolution

Piezoelectric catalytic seawater hydrogen production is one of the most crucial and potential hydrogen production strategies. However, the low surface activity and the high carrier recombination rate limit the further improvement of catalytic efficiency. To solve this problem, we prepared SrBi4Ti4O15 (SBTO) and FeS2 (FS) heterojunctions, which can effectively utilize the valence state transformation cycle between Fe2+ and Fe3+ to improve the surface activity and maintain carrier separation. This mechanism of Fe2+ and Fe3+ conversion is similar to the well-known Fenton reaction. It was confirmed by electrochemical measurements that with the help of FeS2, SBTO possessed a stronger piezoelectric current response and faster carrier transfer rate. Piezoelectric catalytic seawater splitting H2 evolution rate of SBTO-25 %FeS2 could reach 31 mmol g-1h−1, which is higher than that of other piezoelectric materials in similar conditions. Our findings provide valuable insights for further improving the efficiency of seawater hydrogen production efficiency.