Syngas, comprising of carbon monoxide (CO) and hydrogen (H2), serves as a crucial feedstock for a variety of chemical processes including synthetic pathways for alcohols, renewable fuels, and ammonia within fertilizers.[1] Traditionally, syngas is primarily derived from fossil fuels. However, in supporting global decarbonization efforts, there is now a growing necessity in producing syngas from anthropogenic emissions and shift the perspective of CO2 as a waste product to a valuable resource. Carbon capture and electrochemical CO2 reduction technologies present a promising conversion route for the sustainable production of syngas when coupled with renewable electricity.
Current CO2 electrolysers, however, require costly and energy intensive calcination and thermal regeneration capture steps prior to electrolysis. In this work, we demonstrate an integrated carbon capture and electrolysis system for the direct reduction of CO2 into syngas, using a carbon-based molecular electrocatalyst and facilitated by a pH swing mechanism. This system employs a reactive potassium hydroxide (KOH) capture solution, coupled with a membrane electrode assembly and effectively eliminates the need for any additional post-capture separation steps. By employing this integrated system, we produce syngas at the cathode outlet stream with a H2/CO ratio of 1.0 at 200 mA/cm2, corresponding to a CO faradaic efficiency of 49 %.