Title: Predicting Electronic Structure in Tricalcium Silicate Phases with Impurities Using First-Principles
Speaker: Kayahan Saritas (MIT)
Date/Time: 8 July 2015, 13:40-14:30
Place: FENS G029
Abstract: Tricalcium silicate (Ca3SiO5 or C3S) is considered to be the most predominant compound in ordinary Portland cement clinkers, at ∼ 50−70 wt %. From the energy consumption perspective, among other phases in cement, producing C3S requires the highest processing temperature, which accounts for roughly 5% of global CO2 emissions. In this work, using ab-initio calculations, we assess the ability of a large selection of substitutions to modify the electronic structure in the M3 polymorph of tricalcium silicate. We demonstrate the relation between electronic structure, hybridization of the impurity orbitals, and charge transfer from impurity atoms to the bulk material. Our work suggests that charge localization upon introducing impurities can passivate the reactive sites and several such substitutions are identified.
Contact: Cleva Ow Yang