Interface-driven low-dimensional piezo-photocatalysts: Modification strategies for energy and environmental...

Piezo-photocatalysis, which integrates the piezoelectric effect with semiconductor photocatalysis to harvest ambient mechanical energy, offers a promising solution for global energy crises and environmental remediation, yet its practical efficacy remains constrained by the inherent "piezoelectricity-photoactivity" trade-off and detrimental ion-screening effects. Overcoming these bottlenecks dictates a systematic reliance on dimension-oriented interface engineering across low-dimensional (0D, 1D, and 2D) piezoelectric nanomaterials. Rather than treating dimensionality as a secondary morphological trait, this review establishes a comprehensive framework to deconstruct charge carrier dynamics under coupled mechanical, optical, and electrical fields across point-, line-, and face-to-face contact topologies. Mechanistically, we articulate how interface design achieves thermodynamic regulation via defect engineering-specifically optimizing the adsorption free energies of reaction intermediates within dopant-vacancy dipole complexes to lower activation barriers and retard vacancy decay-while simultaneously driving kinetic carrier transport via the piezo-phototronic gating effect to dynamically modulate band structures. Navigating these coupled fields requires the precise implementation of noble-metal-free S-scheme heterojunctions, which exploit work function disparities to trigger a constructive superposition of static internal electric fields and dynamic piezopotentials, thereby accelerating the selective interfacial recombination of low-energy sacrificial carriers while preserving the most potent redox species at the terminal bands. Concurrently, to win the time competition against picosecond-scale electrolyte screening, alternative transient mechanisms like femtosecond-scale ballistic hot-electron injection are highlighted, alongside spatial decoupling strategies-such as core-shell architectures and flexible polymer film encapsulation-that physically shield the internal polarization from electrostatic neutralization without dampening low-frequency stress transfer. Ultimately, this review charts the technological expansion of low-dimensional systems from green hydrogen evolution and selective CO₂ reduction to artificial nitrogen fixation and selective biomass conversion, culminating in a techno-economic roadmap that benchmarks Specific Energy Consumption to transition from energy-intensive artificial ultrasonication to sustainable, low-frequency natural mechanical energy harvesting from river currents and tidal streams for real-world industrial scale-up.