Advances and challenges in electrochemical CO₂reduction processes: an engineering and design perspective looking beyond new catalyst materials

Abstract

This review of design and operating conditions of electrochemical CO2 reduction covers electrolytes, electrodes, reactors, temperature, pressure, and pH effects.

Three-Dimensional Cathodes for Electrochemical Reduction of CO2: From Macro- to Nano-Engineering

“…Calculations using DFT and electro-kinetic models, supported by experimental studies, have been invoked in finding mechanistic interpretations of transitions in Tafel slopes [52,92,255]. CO 2 RR activities of various metal electrodes have been studied with DFT-based computation [255,256]. These studies relate the electro-catalytic activity to the binding energies of chemisorbed reaction intermediates.…”

“…Garg et al recently presented a comprehensive review of CO 2 reduction processes from modeling and design perspectives [256]. The authors highlighted electrolyzer configuration, electrode structure, pH, type of electrolyte, and operating conditions such as pressure and temperature as the most important factors impacting the efficiency of CO 2 reduction processes.…”

“…The majority of modeling studies of mass transport effects in CO 2 RR have explored planar electrodes [115,116,256]. A planar geometry imposes a higher mass transport limitation on the electrochemical cell than that in a 3D porous electrode, which may hinder the transport rate of active species from bulk of electrolyte to the electrode surface [99,262].…”

Highly Efficient Electrochemical CO2 Reduction Reaction to CO with One‐Pot Synthesized Co‐Pyridine‐Derived Catalyst Incorporated in a Nafion‐Based Membrane Electrode Assembly

“…Accelerating the advance of CO 2 utilization is in great demand to create carbon cycle for sustainable human activity. [1] Electrochemical CO 2 reduction reaction (CO 2 RR) [2,3] has attracted attention as an alternative way to produce feedstocks with natural energy resources [4] and reduce carbon emission from fossil fuels. [5] Since pioneering work in the 1980s, [6][7][8] enormous effort has been devoted to the development of new catalytic materials including metal nanoparticles, [9][10][11][12] immobilized metalmacrocycles, [13,14] heteroatom-doped carbon materials, [15,16] and chalcogenides.…”

“…Further increase in the processing temperature led to a decrease in FE, probably due to the dissociation of pyridine moieties [46] and the aggregation of Co. [47] To increase the available catalytic sites, Co-P4VP-derived catalyst was synthesized with a ketjenblack carbon support (ECP600JD) with higher surface and electrochemical active areas (Table S1 and Figure S2, Supporting Information). Processing time, composition, and the catalyst loading [3] were subsequently optimized at 1.5 h, 3 wt% Co composition, and 4 mg cm −2 loading, respectively, leading to a remarkable values for FE (92%) and EE (58%) for CO 2 RR at 85 mA cm −2 ( Figure S3, Supporting Information).…”