Preparation of nanoporous TiOx powder and its enhanced photocatalytic N2 to NH3 conversion by solar-driven interfacial water evaporation

At present, the limited efficiency in ammonia generation poses significant challenge to the widespread practical implementation of photocatalytic nitrogen reduction to ammonia (PNRN). In this study, we synthesized a nanoporous TiO x powder (Alloy-RTO) by rapid breakdown anodization of TA13 alloy and subsequent magnesiothermic reduction. The Alloy-RTO exhibited superior photothermal and photocatalytic properties owing to its multicomponent and interconnective nanoporous structure, and the electronic band structure is suitable for efficient PNRN. Notably, through synergistic integration of PNRN with solar-driven interfacial water evaporation technology (SDIWE), the ammonia production rate was further enhanced, and a multifaceted role of SDIWE in enhancing PNRN was proposed: (1) increasing temperature of Alloy-RTO to promote PNRN; (2) raising temperature to accelerate ammonia water decomposition and facilitate PNRN; and (3) generating plenty of gaseous water to accelerate PNRN. This study presents an effective strategy for preparing nanoporous TiO x and highlights the pivotal role of SDIWE in promoting PNRN.