Double-Layered Sillen–Aurivillius Perovskite Oxybromide Sr₂Bi₃Nb₂O₁₁Br as a Fatigue-Free Piezocatalyst with Ultrahigh Hydrogen Evolution Performance

Piezocatalytic water splitting is an emerging approach for generating green hydrogen by using noise. However, while the efficiency of hydrogen production remains limited, barely anything is known about the long-term usability of the piezocatalysts. In this study, we present single-crystalline Sr2Bi3Nb2O11Br nanoplates with precise facet control and remarkable piezoelectric properties, exhibiting a significantly enhanced piezocatalytic hydrogen production rate of 5.3 mmol/g/h without needing any expensive cocatalyst, such as Pt. Furthermore, we extend the application of these nanoplates to seawater splitting with a commendable rate retention of 4.1 mmol/g/h seawater, mimicking NaCl solution and 3.5 mmol/g/h in real, unprocessed seawater, surpassing the existing piezocatalysts operated using pure water. A key finding in this work is the fatigue-resistant nature of the Sr2Bi3Nb2O11Br nanoplates originating from the layered structure. These maintain ∼100% activity for over 150 h of continuous operation, while the existing catalysts have not been tested beyond 10–15 h, offering a sustainable approach for renewable hydrogen production.