Abel Girma

Donghua University, China

Title: Rational design and synthesis of SnOx electrocatalysts with coralline structure for highly improved aqueous CO2 reduction to formate

---

Biography

Dr. Abel Girma is a PhD candidate since 2015 at the College of Environmental Science and Engineering, Donghua University, Shanghai, China. Abel holds his MSc degree in Environmental Science form Addis Abeba University Ethiopia, in the year 2013 and a BSc degree in Plant Science form Arbaminch University Ethiopia, in the year 2010. Abel has been splendor and highest scorer alumna out of all graduates of Plant Science departments, distinguished from student peers with a track record of superior academic results. Arbaminch University acknowledged and praised him with a medal for his very great distinction performance. Abel’s research interest is related to climate change and water resource allocation with low carbon mode. Abel has a total of 26 publications (7 Sci papers).

Abstract

Several catalyst materials, the tin oxide composites (SnOx) with a novel coralline structure, are synthesized via a facile hydrothermal self-assembled process, and then used to prepare a SnOx/GDL (gas diffusion layer) electrode for CO2 electroreduction to formate in 0.5 M KHCO3 aqueous solution. The influential factors, such as hydrothermal synthesis temperature (T)/time (t) and the valence state of Sn in SnOx nanocatalysts, on both catalysts' morphologies, and Faradaic efficiency for formate production are investigated systematically. Using a SnOx(100-8)/GDL (i.e. T and t are 100 C and 8 hours, respectively) as cathode, the maximum Faradaic efficiency as high as 87.1% is achieved at a controlled potential of -1.6 V, which is superior to all reported SnOx and Sn/SnOx catalysts in literature. By combining XPS and XRD analysis, a coralline structured SnOx is observed to be composed of SnO and SnO2, where the SnO is covered by about 1~2 nm thickness of SnO2 film which makes the contribution to the catalytic active sites for CO2 electroreduction. This coralline structured SnOx exhibits a high durability, as evaluated by a stable catalytic current density of approximately 10 mA cm-2 over 20 hours of continuous operation. This work highlights the controlling role of the correct morphology and the valence state of tin oxide on formate formation during CO2 reduction in aqueous solution.