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The escalating challenges posed by extreme climate change and the rapid greenhouse effect have heightened stress and urgency among governments, researchers, and the public. Greenhouse gas (GHG) emissions, particularly carbon dioxide (CO2), have signi昀椀cantly contributed to rising atmospheric temperatures, with agriculture, forestry, and industrial activities accounting for 22 % and 17 % of global emissions, respectively. In 2022, global GHG emissions reached 53.8 Gt CO2eq, underscoring the critical need for net-zero technologies and a circular carbon economy. This review systematically evaluates the ef昀椀ciencies of non-thermal and electrochemical CO2 conversion technologies, including plasma, arti昀椀cial photosynthesis, and electrochemical methods, for achieving net-zero emissions. These advanced technologies offer promising pathways for converting CO2 into value-added chemicals, such as syngas, methanol, and formic acid, while reducing atmospheric CO2 concentrations. However, upscaling these technologies from laboratory to industrial scales presents signi昀椀cant challenges, including high energy consumption, economic feasibility, and environmental impacts. The review highlights the mechanisms of CO2 conversion, economic considerations, and the potential for industrial implementation. Priority research directions are identi昀椀ed, focusing on ecological footprints, green supply chains, and the integration of renewable energy sources. By addressing these challenges, non-thermal and electrochemical CO2 conversion technologies can play a pivotal role in mitigating climate change and advancing toward a sustainable, circular carbon economy.
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This content will become publicly available on August 1, 2026
Time dependence of corrosion resistance in belitic calcium sulfoaluminate (BCSA) cement concrete
This paper studies the time dependence of corrosion resistance in belitic calcium sulfoaluminate (BCSA) cement concrete. BCSA is a hydraulic cement that sets rapidly and has a lower carbon footprint than portland cement (PC). Some studies suggest that BCSA concrete is highly susceptible to chloride-induced corrosion, but these claims are based on testing at 28 days. No later-age results have been reported. We con昀椀rm that BCSA cement concrete exhibits poor corrosion resistance when tested at 28 days, which can be attributed to an immature microstructure with weak resistance to chloride ingress and a pore solution that does not support passivation. We further show that corrosion resistance improves signi昀椀cantly as the BCSA system matures, achieving good corrosion resistance between 90 and 180 days. This improvement relates to the slow hydration of belite, which results in signi昀椀cant later-age microstructure re昀椀nement and probably alters the pore solution in a way that promotes or enhances steel passivation.
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- Award ID(s):
- 2338531
- PAR ID:
- 10587029
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Cement and Concrete Composites
- Volume:
- 161
- ISSN:
- 0958-9465
- Page Range / eLocation ID:
- 106099
- Subject(s) / Keyword(s):
- Belite Calcium sulfoaluminate Corrosion Maturity Pore solution
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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