In recent years, the emissions of carbon dioxide (CO₂) into atmosphere caused by industrial production has been considered to be one of the main causes of global warming, which has recently attracted much attention¹. Electrochemical reduction of CO₂ could provide an attractive solution to this climate issue with CO₂ converted into useful fuels such as formic acid, methane, methanol, ethylene, etc., which represents a value-added path that can simultaneously produce alternative fuels and remedy the carbon emissions generated by conventional fuels². Metal catalysts have been demonstrated effectively and widely used materials to obtain formate by reducing CO₂. Among these metals, tin or copper-tin alloys are excellent candidates regarding to CO₂ electroreduction to produce formate fuel. However, the fabrication production of catalysts is complicated for practical application, as the synthetic process need high-temperature calefaction or the addition of expensive additives³.

Electrodeposition with hydrogen bubble template in aqueous solution is a facile, low-energy method, which can easily create a 3D structure so that can provide large specific surface area on the substrate. Meanwhile, the porous foam attributed to concurrent hydrogen bubbles with different deposition time has a distinct impact on the catalytic activity and selectivity during CO₂ electrochemical reduction. By applying electrodeposition methods, we have successfully synthesized the Sn@Cu catalysts, which was controlled by simply adjusting the electrodeposition time. As demonstrated by both CV and LSV results, highly selective HCOO^- production (Faradaic efficiency = 86.7%) can be realized at a potential of -1.6 V vs. SCE with really high current density greater than 10 mA cm^-2.

References

[1]. J.L. Qiao; M.Y. Fan; Y.S. Fu; Z. Bai; C. Ma; Y. Liu; X.D. Zhou, Electrochim. Acta, 153, 559 (2015)

[2]. Y. Wang; J. Zhou; W. Lv; H. Fang; W. Wang, Appl. Surf. Sci., 362, 394 (2016)

[3]. X. Zhang; T. Lei; Y.Y. Liu; J.L. Qiao, Appl. Catal., B, 218, 46(2017)