A novel unipolar pulsepotential oscillation system based on HKUST-1(C) @CoAl LDH film for selective separation of dodecyl sulfonate ions

A carbonized HKUST-1@CoAl layered double hydroxide (HKUST-1(C)@CoAl LDH) film with a threedimensional (3D) porous structurewas successfully prepared on the copper mesh by using a two-step electrochemical deposition method, and applied in a novel unipolar pulse potential oscillation (UPPO) system for selective separation of dilute dodecyl sulfonate ions (DS- ). In the HKUST-1(C)@CoAl LDH film, the CoAl LDH was served as a separating layer to improve the selectivity for DS- ions with the HKUST-1(C) as a storage layer to increase the adsorption amount of DS- ions. As a result, the 3D HKUST-1(C)@CoAl LDH film coated electrode showed excellent selectivity toward DS- ions with a high adsorption capacity of 733.84 mg g-1 and favorable electrochemical stability. More importantly, it is found that such a novel UPPO system can effectively reduce the influence of co-existing anions on the adsorption of DS- ions and accelerate the transport of DS- ions in the film by the periodic potential oscillation, which is expected to be used for the selective separation of DS- ions from practical wastewater.

Automated summary

A carbonized HKUST-1@CoAl layered double hydroxide film with a 3D porous structure was successfully prepared and applied in a novel UPPO system for selective separation of dilute DS- ions. The film showed excellent selectivity, high adsorption capacity, and good electrochemical stability.