Hydrothermally Controllable Fabrication of Bi2WO6 Nanocapsules Decorated by CuO Nanorods with Enhanced Visible Photocatalytic Performance

A Bi2WO6 nanocapsules-like structure decorated by CuO nanorods for the construction of n-p heterojunction CuO/Bi2WO6 nanocomposites was developed through a facile two-step process, which utilized a hydrothermal approach. The optical properties and structural morphology of CuO/Bi2WO6 nanocomposite photocatalysts were demonstrated. The synthesized photocatalysts were assessed via the degradation of acridine orange (AO) dye as the target pollutant under visible illumination. The 15% CuO/Bi2WO6 nanocomposite showed the highest photocatalytic ability, which oxidized 100% of the AO dye within 40 min. The 15% CuO/Bi2WO6 nanocomposite showed the highest rate constant of 0.0484 min- 1 for AO dye, which was approximately 4.75-and 4.28-fold larger than those of Bi2WO6 (0.0102 min-1) and CuO (0.0113 min-1), respectively. The enhanced photo -catalytic abilities of the CuO/Bi2WO6 nanocomposites were attributed to the strengthening absorption of visible light, the construction of the n-p heterojunction, the effective charge separation according to the S-scheme mechanism and the extended carrier lifetime, which efficiently suppressed photoinduced electron/hole recom-bination. The obtained CuO/Bi2WO6 nanocomposites were stable over five consecutive cycles with almost constant degradation ability. Therefore, due to their promising photocatalytic abilities, the CuO/Bi2WO6 nanocomposites are suitable photocatalysts for environmental treatment applications.