CuS/TiO2 nanotube arrays heterojunction for the photoreduction of uranium (VI)

The separation of uranium U(VI) through photoreduction approach has attracted substantial attention. Sulfide-based materials have revealed excellent performance for reducing U(VI) and there is no record of CuS based materials. Herein, we synthesized CuS/TNTAs heterostructured nanocomposites (CUTN) with varied CuS contents via successive ionic layer adsorption and reaction (SILAR) method. After SILAR deposition for 10 times, CUTN-10 showed the best photocatalytic performance, and 92.6 ​% of U(VI) can be removed within 180 ​min. The CuS could provide sufficient photoelectrons and TNTAs can transport these photoelectrons to the adsorbed U(VI) on its surface, the reduced uranium sediment was proved to be (UO2) O2·2H2O. More important, the combination of TNTAs could effective inhibit photocorrosion of CuS and the leaching of Cu2+ was relatively low. We also unconsciously found that CUTN-10 can photoreduce U(VI) without any sacrificial agent which caused by the oxidation of S2−. This work expands the application of sulfide-based materials and provides basic data for bracing the expansion of sulfide-based materials in the field of U(VI) photoreduction.