This study presents a novel approach to green piezo-catalysis by fabricating hierarchically porous ferroelectric ceramics, specifically Ba₀.₇₅Sr₀.₂₅TiO₃ (BST), using a combination of direct ink writing (DIW) and freeze casting (FC). The hierarchical pore structure enhances the piezo-catalytic performance by increasing the surface area and improving the accessibility of the catalyst to reactants. The BST ceramics were synthesized with micro- and macro-pores, resulting in a high first-order kinetic rate constant (k) of 2.91 min⁻¹ kg⁻¹ and an average hydrogen production rate of 848.88 nmol g⁻¹ h⁻¹. The hierarchical pore structure also facilitates efficient dye degradation and water splitting, with a degradation rate of 90.3% for Rhodamine B. The study demonstrates that the hierarchical porous structure significantly improves the catalytic performance compared to traditional powder-based catalysts, which are difficult to recycle and cause secondary pollution. The fabricated BST ceramics exhibit excellent mechanical stability and maintain their catalytic activity over multiple cycles. The results highlight the potential of hierarchically porous ferroelectric ceramics for sustainable piezo-catalytic applications in water treatment and hydrogen production. The study also provides insights into the mechanisms of piezo-catalysis, including the role of spontaneous polarization and the generation of surface charges under ultrasound. The findings suggest that the combination of DIW and FC techniques is an effective method for producing retrievable, porous ferroelectric ceramics with enhanced piezo-catalytic properties.This study presents a novel approach to green piezo-catalysis by fabricating hierarchically porous ferroelectric ceramics, specifically Ba₀.₇₅Sr₀.₂₅TiO₃ (BST), using a combination of direct ink writing (DIW) and freeze casting (FC). The hierarchical pore structure enhances the piezo-catalytic performance by increasing the surface area and improving the accessibility of the catalyst to reactants. The BST ceramics were synthesized with micro- and macro-pores, resulting in a high first-order kinetic rate constant (k) of 2.91 min⁻¹ kg⁻¹ and an average hydrogen production rate of 848.88 nmol g⁻¹ h⁻¹. The hierarchical pore structure also facilitates efficient dye degradation and water splitting, with a degradation rate of 90.3% for Rhodamine B. The study demonstrates that the hierarchical porous structure significantly improves the catalytic performance compared to traditional powder-based catalysts, which are difficult to recycle and cause secondary pollution. The fabricated BST ceramics exhibit excellent mechanical stability and maintain their catalytic activity over multiple cycles. The results highlight the potential of hierarchically porous ferroelectric ceramics for sustainable piezo-catalytic applications in water treatment and hydrogen production. The study also provides insights into the mechanisms of piezo-catalysis, including the role of spontaneous polarization and the generation of surface charges under ultrasound. The findings suggest that the combination of DIW and FC techniques is an effective method for producing retrievable, porous ferroelectric ceramics with enhanced piezo-catalytic properties.