Interconnected Periodic Macroporous NaNbO₃ for High-Efficiency Solar-Driven Photocatalytic Hydrogen Evolution

Highly ordered periodic macroporous structures have been extensively utilized to significantly enhance the photocatalytic activity. However, constructing 3D interconnected ordered porous ternary nanostructures with highly crystalline frameworks remains a formidable challenge. Here, we introduce the design and fabrication of 3D interconnected periodic macroporous NaNbO₃ (PM NaNbO₃) to effectively increase the density of surface-active sites and optimize the photogenerated carrier-transfer efficiency. By incorporating Pt as a cocatalyst, PM NaNbO₃ exhibits an exceptional photocatalytic hydrogen generation rate of 10.04 mmol h^-1 g^-1, which is approximately six and five times higher than those of calcined NaNbO₃ (C-NaNbO₃) and hydrothermal NaNbO₃ (H-NaNbO₃), respectively. This outstanding performance can be attributed to the synergistic effects arising from its well-interconnected pore architecture, large surface area, enhanced light absorption capability, and improved charge carrier separation and transport efficiency. The findings presented in this study demonstrate an innovative approach toward designing hierarchically periodic macroporous materials for solar-driven hydrogen production.