A system and method are disclosed for increasing the production yield of CO.sub.2 conversion products in an electrochemical reactor assisted by an osmotically driven dewatering system. The system comprises an electrochemical cell including a cathode chamber, an anode chamber, and a central desalination chamber. The cathode chamber includes a cathode active material, and the anode chamber includes an anode active material. The central desalination chamber comprises a plurality of desalination cells, each featuring alternating anion exchange membranes (AEMs) and cation exchange membranes (CEMs). A forward osmosis membrane (FOM) is integrated at the interface between the cathode chamber and the adjacent desalination cell, replacing the conventional terminal CEM. This configuration establishes an osmotic gradient that drives water flux from the cathode chamber into the desalination chamber, thereby concentrating the CO.sub.2 conversion product (e.g., formate) in situ and enhancing Faradaic efficiency without requiring post-treatment.

The present disclosure discloses a system and a method for solar-driven photothermal seawater desalination and ion electroosmosis power generation. In the system, a first reservoir is provided with a first electrode immersed in seawater; a second reservoir is connected to the first reservoir via a cation selective nanofilm; a third reservoir is provided with a second electrode immersed in seawater, and the third reservoir is connected to the second reservoir via an anion selective nanofilm; and an adjustable sun-visor shields the cation selective nanofilm to form a first preset part of solar illumination and shields the anion selective nanofilm to form a second preset part of the solar illumination. Therefore, the cation selective nanofilm and the anion selective nanofilm are each under an asymmetric illumination to generate a temperature gradient.