The electrocatalytic reduction of carbon dioxide (CO) using new energy and electrical energy can convert CO into value-added chemicals while reducing carbon emissions, which has broad application prospects. Among the various reduction products, formic acid(HCOOH) is easy to store and transport, with a high storage density of hydrogen. Tin oxide ( SnO ) electrocatalytic materials arelow-cost and less toxic, while SnO is highly selective for HCOOH when used for electrocatalytic reduction of CO.In the industrializationof electrocatalytic reduction, a reasonable electrolytic reactor structure is of great significance. To explore a more reasonable electrolytic reactor structure, this paper proposes a homemade multilayer stacked electrolytic reactor, in which SnO nanoparticles prepared by flamespray pyrolysis method are used as electrocatalysts for electrocatalytic reduction of CO.The effects of parameters such as cathode-anodespacing, electrolyte flow rate, electrolyte concentration and the number of electrode stacks on the electrocatalytic performance of the electrolytic cell were investigated. The experimental results show that: the closer the cathode-anode distance is, the lower the electrical energyloss is, and the catalyst has better catalytic performance; the flow rate of the electrolyte has no significant effect on the reduction performance of the catalyst, but when the flow rate is too fast, the current density of the reaction produces a more drastic fluctuation. When theelectrolyte concentration was less than 1 mol/ L, the selectivity of the catalyst for HCOOH increased with the increase of the electrolyte concentration, whereas the selectivity of the catalyst for each product stabilized at the electrolyte concentration of more than 1 mol/ L.The current density decreased slightly when the electrodes were placed in stacks, but the overall Faraday efficiency and the Faraday efficiency of HCOOH both increased, and the hydrogen precipitation reaction was suppressed more significantly. The charge transferresistance and diffusion resistance were reduced when using a stack electrolytic reactor. The optimum Faraday efficiency for HCCOHof SnO under stack conditions reaches 37.53% and the total Faraday efficiency reaches 75.83% with the cathode - anode spacing of10 mm, the applied potential of -1.2 V vs. RHE, and the KHCO concentration of 1 mol/ L. The results indicate that the catalytic performance of the catalyst and the selectivity of the target products can be enhanced by using a stacked electrolytic reactor.

魏书洲(1981—),男,湖北十堰人,高级工程师,博士.E-mail:shuzhou.wei@chnenergy.com.cn

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WEI Shuzhou,TAN Shuting,XIONG Zhuo,et al.Experimental study of electrocatalytic CO2 reduction by nano-SnO2basedon stacked electrolytic reactor[J].Clean Coal Technology,2024,30(8):99-106.