Abstract:
Utilizing solar energy and mechanical vibration energy for hydrogen production while simultaneously degrading pollutants is a highly promising strategy to address energy shortages and environmental pollution. Traditional photocatalytic hydrogen production relies on hole scavengers and co-catalysts, leading to resource waste and increased costs. In this study, one-dimensional ZnFe
2O
4/NaNbO
3 composite nanorods were prepared via a hydrothermal-sintering method. Narrow band-gap ZnFe
2O
4 was in-situ grown on the surface of piezoelectric NaNbO
3 nanorods, achieving deep synergy among broadened visible-light response, piezoelectric effect, and S-scheme charge transfer. This system eliminates the need for expensive sacrificial agents and co-catalysts. By employing Tetracycline (TC) as the hole scavenger, it achieves concurrent high-efficiency hydrogen evolution and pollutant degradation. Photoelectrochemical, XPS, and radical trapping results confirm that the built-in electric field drives directional electron transfer from NaNbO
3 to ZnFe
2O
4, following an S-scheme transfer mechanism. The one-dimensional nanorods provide a rapid electron transport channel, while the ultrasound-induced piezoelectric field tilts the energy bands of NaNbO
3, accelerating charge carrier separation and migration. Under photo-ultrasound synergy, 20ZnFe
2O
4/NaNbO
3 exhibited an H
2 evolution rate of 723.3 μmol·h
−1·g
−1 and 79.6% TC degradation. In the coupled H
2 evolution-degradation system, theH
2 production rate reached 357.36 μmol·h
−1·g
−1 over 5 h with 66.4% simultaneous TC degradation. This work demonstrates the synergistic enhancement mechanism between the S-scheme heterojunction and piezoelectric effect, offering insights for designing efficient, dual-functional piezo-photocatalysts free of sacrificial agents and co-catalysts.