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

The separation of uranium U(VI) through photoreduction approach has attracted substantial attention. Sulfidebased 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)O-2 center dot 2H(2)O. 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.

Automated summary

The study successfully synthesized CuS/TNTAs heterostructured nanocomposites (CUTN) with different CuS contents via successive ionic layer adsorption and reaction (SILAR) method. CUTN-10 exhibited the best photocatalytic performance, removing 92.6% of U(VI) within 180 minutes. The CuS provided photoelectrons, and TNTAs transported them to the adsorbed U(VI) surface, leading to reduced uranium sediment in the form of (UO2)O·2H2O.