Controlling the Interaction Between Carbon Dioxide and Cementitious Materials Using Biomimetic Molecules

University Of Texas At Arlington, Arlington TX

Investigators

Abstract

This research aims to make sustainable infrastructure materials, including supplementary cementitious materials (SCMs) and alkali-activated materials (AAM), last longer by reducing their deterioration when these are exposed to carbon dioxide. This research will further contribute to the low-carbon future by advancing the understanding and applications of cementitious materials that can directly serve as carbon dioxide sinks. The outreach effort of this research involves developing a multidisciplinary workforce with faculty members and students from civil engineering, materials science, and chemistry to address the challenges of creating sustainable and durable materials for civil infrastructures. The direct educational benefits include mentored research opportunities for undergraduate and high school students as well as underrepresented groups. These opportunities will provide students with exposure to advanced research facilities and motivate them to pursue higher education in the field of infrastructure materials. This research will capitalize on the biomimetic approaches of engineering the growth, aggregation, and characteristics of in-situ precipitated calcium carbonate particles to control the interaction between cementitious materials and carbon dioxide. The specific objectives include: (i) determining the effectiveness of in-situ precipitated metastable calcium carbonate (mCaCO3) and calcium carbonate-organic hybrid (mCOH) phases to avoid degradation of calcium silicate hydrate (C-S-H) and calcium aluminum silicate hydrate (C-A-S-H) gel phases when exposed to external carbon dioxide, thus enhancing the carbonation resistance of cementitious composites containing AAMs and SCMs; (ii) investigating how biomimetic molecules can be used to precipitate specific mCaCO3 with controlled morphologies and properties in carbonation cured matrices so that their in-situ formations can be leveraged to develop high-performance cementitious matrices; (iii) investigating the functional relationship between biomimetic molecules and the polymorphic crystallization of calcium carbonate particles, and therefore, developing non-natural and affordable biomimetic molecules that can be used as chemical admixtures in cementitious materials. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.