Journal Article

Electrochemical direct air capture of CO2 using neutral red as reversible redox-active material

Seo, Hyowon, Hatton, T. Alan

2023

Overview

Direct air capture of carbon dioxide is a viable option for the mitigation of CO 2 emissions and their impact on global climate change. Conventional processes for carbon capture from ambient air require 230 to 800 kJ thermal per mole of CO 2 , which accounts for most of the total cost of capture. Here, we demonstrate electrochemical direct air capture using neutral red as a redox-active material in an aqueous solution enabled by the inclusion of nicotinamide as a hydrotropic solubilizing agent. The electrochemical system demonstrates a high electron utilization of 0.71 in a continuous flow cell with an estimated minimum work of 35 kJ e per mole of CO 2 from 15% CO 2 . Further exploration using ambient air (410 ppm CO 2 in the presence of 20% oxygen) as a feed gas shows electron utilization of 0.38 in a continuous flow cell to provide an estimated minimum work of 65 kJ e per mole of CO 2 . Electrochemical direct air capture (DAC) of CO 2 requires air-stable redox-active materials. Here, the authors present an electrochemical DAC using air-stable redox couple of neutral red with a minimum energy requirement of 65 kJ e /mol CO2 .

• Publisher: Nature Publishing Group UK,Nature Publishing Group,Nature Portfolio
• Subject: 140/131 / 639/166/898 / 639/4077/4057 / Aqueous solutions / Carbon capture and storage / Carbon dioxide / Carbon dioxide emissions / Carbon sequestration / Chemical engineering / Climate change / Continuous flow / Electrochemistry / Emissions / Global climate / Humanities and Social Sciences / INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY / multidisciplinary / Nicotinamide / Science / Science & Technology / Science (multidisciplinary)