On the Role of Sulfur for the Selective Electrochemical Reduction of CO 2 to Formate on CuS x Catalysts

Yilin Deng, Yun Huang, Dan Ren, Albertus D Handoko, Zhi Wei Seh, Pussana Hirunsit, Boon Siang Yeo
ACS Applied Materials & Interfaces 2018 August 29, 10 (34): 28572-28581
The efficient electroreduction of CO2 has received significant attention as it is one of the crucial means to develop a closed-loop anthropogenic carbon cycle. Here, we describe the mechanistic workings of an electrochemically deposited CuS x catalyst that can reduce CO2 to formate with a Faradaic efficiency (FEHCOO - ) of 75% and geometric current density ( jHCOO - ) of -9.0 mA/cm2 at -0.9 V versus the reversible hydrogen electrode. At this potential, the formation of other CO2 reduction products such as hydrocarbons and CO was notably suppressed (total FE < 4%). The formate intermediate (HCOO*) was identified by operando Raman spectroscopy with isotopic labeling. A combination of electrochemical and materials characterization techniques revealed that the high selectivity toward formate production can be attributed to the effect of S dopants on the Cu catalyst, rather than surface morphology. Density functional theory calculations showed that the presence of sulfur weakens the HCOO* and *COOH adsorption energies, such that the formation of *COOH toward CO is suppressed, while the formation of HCOO* toward formate is favored.


You are not logged in. Sign Up or Log In to join the discussion.

Related Papers

Available on the App Store

Available on the Play Store
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"