Electrocatalytic reduction of CO2 to formate using particulate Sn electrodes: Effect of metal loading and particle size

• Published in: Applied energy 2015-11, Vol.157, p.165-173
• Main Authors: Del Castillo, A., Alvarez-Guerra, M., Solla-Gullón, J., Sáez, A., Montiel, V., Irabien, A.
• Format: Article
• Language: English
• Subjects: Carbon dioxide; Electroreduction; Formate; Tin particles; Valorization
• ISSN: 0306-2619; 1872-9118
• DOI: 10.1016/j.apenergy.2015.08.012

[Display omitted] •The continuous electroreduction of CO2 to formate was studied.•The influence of Sn particle load and size was studied by electrochemical characterization.•Electrodes with 0.75mgSncm−2 of 150nm particles gave the best results.•Formate was obtained in continuous mode with a single pass in a filter-press cell.•High faradaic efficiency, formate rate and concentration were obtained at 90mAcm−2. The development of electrochemical processes for the conversion of CO2 into value-added products allows innovative carbon capture & utilization (CCU) instead of carbon capture & storage (CCS). In addition, coupling this conversion with renewable energy sources would make it possible to chemically store electricity from these intermittent renewable sources. The electroreduction of CO2 to formate in aqueous solution has been performed using Sn particles deposited over a carbon support. The effect of the particle size and Sn metal loading has been evaluated using cyclic voltammetry and chronoamperometry. The selected electrode has been tested on an experimental filter-press type cell system for continuous and single pass CO2 electroreduction to obtain formate as main product at ambient pressure and temperature. Experimental results show that using electrodes with 0.75mgSncm−2, 150nmSn particles, and working at a current density of 90mAcm−2, it is possible to achieve rates of formate production over 3.2mmolm−2s−1 and faradaic efficiencies around 70% for 90min of continuous operation. These experimental conditions allow formate concentrations of about 1.5gL−1 to be obtained on a continuous mode and with a single pass of catholyte through the cell.