A Novel 3DOM TiO₂ Based Multifunctional Photocatalytic and Catalytic Platform for Energy Regeneration and Pollutants Degradation

The ternary 3D ordered macroporous (3DOM) heterojuncted nanocomposites (platinum/bismuth molybdate/3DOM TiO₂: 3DOM-Pt/Bi₂MoO₆/TiO₂) are designed and synthesized as multifunctional platform for photocatalytic dye degradation, photoelectrocatalytic (PEC) water splitting, and thermal-catalytic toluene decomposition with high performance. A series of structural, optical, and electronic characterizations demonstrates that the remarkably improved photocatalytic degradation and PEC water splitting activities are attributed to the combined effects of enhanced light harvesting, abundant reactive sites, facile reactants transfer, and efficient charges–holes pair separation. Through optimizing the loading amounts of Pt and Bi₂MoO₆, it is found that the 1%Pt/10%Bi₂MoO₆/TiO₂ nanocomposite exhibits the highest photocatalytic Rhodamin B (RhB) degradation rate and PEC water splitting activity, which are 10 and 2.2 times higher than that of the titania photonic crystal (PC-TiO₂) photocatalyst, respectively. This work clearly illustrates that the ternary photocatalyst with 3DOM structure and intimate heterostructure can significantly facilitate the transfer of reaction intermediates and the separation of photogenerated carriers. Considering its unique 3DOM structure and excellent photocatalytic/PEC performances, the ternary nanocomposite has been used in catalytic toluene decomposition and inspiringly shows high efficiency, being very promising in thermocatalytic applications. This work provides new solutions in developing new ternary nanocomposites for versatile applications in photocatalytic, photoelectrochemical, and catalytic fields.