Construction Materials & Geopolymers

Concrete is the most prevalent building material on the planet, and the global concrete industry emits around 5-8% of all human-generated atmospheric CO2. A class of alkali-activated concrete binders known as "geopolymers" provide an environmentally friendly alternative to conventional cements. Alkali activation technology offers reduced CO2 emission by 80-90% relative to ordinary Portland cement, and is primarily based around the use of industrial wastes and clay, including fly ash, granulated ground blast furnace slag and metakaolin, as precursors. While highly promising for "green" construction materials, several crucial aspects of geopolymer structure are not yet well understood at the nanoscale, in particular, the role of metallic impurities and the possibility of toxin release from reused waste material into the environment. The interesting length scale for these composite materials is a few 10s of nanometers. Our research explores these materials primarily by the use of high-resolution x-ray fluorescence and tomography.

Selected Publications

Qinang Hu, Mohammed Aboustait, Taehwan Kima, M. Tyler Ley, Jay C. Hanan, Jeffrey Bullard, Robert Winarski, Volker Rose, "Direct three-dimensional observation of the microstructure and chemistry of C3S hydration", Cement and Concrete Research 88, 157-169 (2016). Susan A. Bernal, Volker Rose, John L. Provis, "The fate of iron in blast furnace slag particles during alkali-activation", Mater. Chem. Phys. 146, 1 (2014). Susan A. Bernal, John L. Provis, Volker Rose, Ruby Mejía de Gutiérrez, "High-Resolution X-ray Diffraction and Fluorescence Microscopy Characterization of Alkali-Activated Slag-Metakaolin Binders", J. Am. Ceram. Soc. 96, 1951 (2013). J. L. Provis, R.J. Myers, C.E. White, V. Rose, J.S.J. van Deventer, “X-ray microtomography shows pore structure and tortuosity in alkali-activated binders”, Cem. Concr. Res. 42, 855 (2012). J. L. Provis, V. Rose, R. P. Winarski, J.S.J van Deventer, “Hard X-ray nanotomography of amorphous aluminosilicate cements”, Scripta Materialia 65, 316 (2011). S. A. Bernal, R. M. de Gutierrez, J. L. Provis, V. Rose, “Effect of silicate modulus and metakaolin incorporation on the carbonation of alkali silicate-activated slags”, Cem. Concr. Res. 40, 898 (2010). J.L. Provis, V. Rose, S.A. Bernal, J.S.J. van Deventer, “High resolution Nanoprobe X-ray fluorescence characterization of heterogeneous calcium and heavy metal distribution in alkali activated fly ash”, Langmuir 25, 11897 (2009).

 

03.21.2018