Polythiophene-decorated copper via polypyrrole intermediary passivation layer for enhanced electrocatalytic reduction of carbon dioxide

Author(s)

Venkatkarthick, Radhakrishnan ; Lima, Fabio H. B.

• Document type: Journal article
• Source: JOURNAL OF ELECTROANALYTICAL CHEMISTRY; v. 961, p. 12-pg., 2024-04-08.

Abstract

Copper is unique in catalyzing the electrochemical reduction of carbon dioxide (CO2RR) to produce C2+ hydrocarbons, but pristine Cu has a low selectivity and stability. In this study, a multilayered, N and S-containing polymer, polypyrrole (PPy), and polythiophene (PTh) were electrodeposited on polycrystalline Cu surface, and the CO2RR catalytic activity was investigated via Electrochemical Mass Spectrometry (EC-MS), Gas (GC) and Liquid (HPLC) Chromatography techniques. The PTh-PPy-Cu electrode exhibited lower CO2RR onset potential (-0.6 V vs RHE) and higher selectivity towards ethylene formation, when compared to bare Cu electrodes, as revealed by the EC-MS measurements. GC analyses also revealed that the PTh-PPy-Cu electrode exhibits higher faradaic efficiency for ethylene production than bare Cu (FE similar to 1.4 to 7.0 %) at a relatively low overpotential (-1.0 V vs RHE). The improved selectivity of PTh-PPy-Cu for C2H4 was mainly attributed to the in-situ generated surface defects (grain boundaries), stabilized by the PTh overlayer, and to the strong hydrophobic characteristic of the polymer layer. This study could pave the way for fine-tuning the catalytic activity, selectivity, and stability of copper-containing catalysts by utilizing surface modification of metallic catalysts toward the CO2RR. (AU)

• FAPESP's process: 21/13985-1 - Surface modifications of copper electrocatalysts: a strategy to increase selectivity and stability for electro-reduction of carbon dioxide
• Grantee: Antonio Carlos Roveda Júnior
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 19/22183-6 - Electrocatalysis VI: fundamental and applied aspects of emerging and classical problems in electrochemical energy conversion
• Grantee: Edson Antonio Ticianelli
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 20/15230-5 - Research Centre for Greenhouse Gas Innovation - RCG2I
• Grantee: Julio Romano Meneghini
• Support Opportunities: Research Grants - Research Centers in Engineering Program
• FAPESP's process: 14/50279-4 - Brasil Research Centre for Gas Innovation
• Grantee: Julio Romano Meneghini
• Support Opportunities: Research Grants - Research Centers in Engineering Program
• FAPESP's process: 22/07207-9 - Au and Cu-based electrodes superficially modified with functional molecules with alkaline and hydrophobic groups for carbon dioxide reduction
• Grantee: Radhakrishnan Venkatkarthick
• Support Opportunities: Scholarships in Brazil - Post-Doctoral