Removal of non-CO2 greenhouse gases by large-scale atmospheric solar photocatalysis


Large-scale atmospheric removal of greenhouse gases (GHGs) including methane, nitrous oxide and ozone-depleting halocarbons could reduce global warming more quickly than atmospheric removal of CO2. Photocatalysis of methane oxidizes it to CO2, effectively reducing its global warming potential (GWP) by at least 90%. Nitrous oxide can be reduced to nitrogen and oxygen by photocatalysis; meanwhile halocarbons can be mineralized by red-ox photocatalytic reactions to acid halides and CO2. Photocatalysis avoids the need for capture and sequestration of these atmospheric components. Here review an unusual hybrid device combining photocatalysis with carbon-free electricity with no-intermittency based on the solar updraft chimney. Then we review experimental evidence regarding photocatalytic transformations of non-CO2 GHGs. We propose to combine TiO2-photocatalysis with solar chimney power plants (SCPPs) to cleanse the atmosphere of non-CO2 GHGs. Worldwide installation of 50,000 SCPPs, each of capacity 200 MW, would generate a cumulative 34 PWh of renewable electricity by 2050, taking into account construction time. These SCPPs equipped with photocatalyst would process 1 atmospheric volume each 14–16 years, reducing or stopping the atmospheric growth rate of the non-CO2 GHGs and progressively reducing their atmospheric concentrations. Removal of methane, as compared to other GHGs, has enhanced efficacy in reducing radiative forcing because it liberates more °OH radicals to accelerate the cleaning of the troposphere. The overall reduction in non-CO2 GHG concentration would help to limit global temperature rise. By physically linking greenhouse gas removal to renewable electricity generation, the hybrid concept would avoid the moral hazard associated with most other climate engineering proposals.

Publication DOI:
Divisions: College of Engineering & Physical Sciences > School of Engineering and Technology > Mechanical, Biomedical & Design
College of Engineering & Physical Sciences > Sustainable environment research group
College of Engineering & Physical Sciences > Aston Institute of Materials Research (AIMR)
Additional Information: © 2017 The Authors. Published by Elsevier Ltd. This is an open access article article under the CC BY license (
Uncontrolled Keywords: atmospheric greenhouse gas removal,GHG photocatalysis,giant photocatalytic reactor,large scale atmospheric air cleansing,negative emissions technology,solar chimney power plant,solar-wind hybrid,Chemical Engineering(all),Fuel Technology,Energy Engineering and Power Technology
Publication ISSN: 0360-1285
Last Modified: 17 Jun 2024 07:24
Date Deposited: 19 Aug 2019 10:09
Full Text Link:
Related URLs: http://www.scop ... tnerID=8YFLogxK (Scopus URL)
PURE Output Type: Review article
Published Date: 2017-05
Published Online Date: 2017-01-24
Accepted Date: 2017-01-12
Submitted Date: 2016-05-21
Authors: de Richter, Renaud
Ming, Tingzhen
Davies, Philip (ORCID Profile 0000-0003-4783-1234)
Liu, Wei
Caillol, Sylvain



Version: Published Version

License: Creative Commons Attribution

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