Morphological reconstruction and photocatalytic enhancement of NaTaO3 nanocrystals via Cu2O loading

This work reported on the synthesis of Cu2O/NaTaO3 heterojunctions with controlled morphology and tunable photocatalytic property. The samples were carefully characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, UV–Vis diffuse reflectance spectroscopy, and photocatalytic test. It is found that Cu2O anchoring on NaTaO3 led to the morphological reconstruction of NaTaO3 nanocrystals. The irregularly shaped and aggregated NaTaO3 nanocrystals reconstructed to microcubes with the diameter of about 1–2 μm, which led to fine interparticle interaction between Cu2O and NaTaO3. Furthermore, the heterojunction of Cu2O with NaTaO3 nanocrystals also led to highly enhanced photocatalytic activities, which can be attributed to efficient separation of the electron–hole pairs between Cu2O and NaTaO3, giving rise to potential difference at the p–n junction interface, reducing the chance of electron–hole pair recombination, and increasing the photocatalytic activities. With well-controlled morphology and electronic structure, the photocatalytic performance of Cu2O/NaTaO3 heterojunctions was optimized at Cu content of 0.25 wt%.