Research
My work at LLNL is partially non-disclosed, see public information below.
Materials
Materials for decarbonization. Concrete is the second most used material on the earth, after water. Cement, the glue for concrete, is responsible for 8% of global CO2 emission and 5% of energy use. How to decarbonize carbon-intensive cement, convert CO2 to carbon-negative cement, and co-benefit other industries?
Replacing cement with energy industry's byproducts can significantly decarbonize different sectors. These low- or carbon-negative materials exhibit higher performance than ordinary cement.
Past research focuses on understanding the chemistry and multi-scale structure of the materials, as well as the intrinsic mechanical properties of the phases in the systems. Potential solutions to further reduce the environmental impacts of the systems are being explored (non-discolosed).
At LLNL, Jiaqi uses isotopes and highly pure cement minerals.
Nanostructure of low-carbon cement
Experimental tools
To tackle complicated problems and understand the nature of complex low-carbon or carbon-negative materials, state-of-the-art experimental tools are necessary, such as advanced synchrotron-radiation-based characterization techniques (X-ray Absorption Near-Edge Structure, Soft X-ray Ptychography, High-Pressure X-Ray Diffraction, High-Pressure X-ray Raman Scattering Spectroscopy, Micro Computed Tomography). Conventional tools are also useful (e.g., calorimeter, rheometer)
At LLNL, Jiaqi is responsible for ~$1 million value of instruments, including concrete 3D printer, focused beam reflectance measurement, isothermal calorimeter, particle size analyzer, gas chromatography, thermogravimetric analyzer, mass spectrometer, rheometer, CO2 incubator, high-temperature furnace, vacuum oven, potentiostat, booster, large reactors, centrifuge, etc.
Concrete microstructure using μCT
Modelling
Modeling approaches are powerful to unveiling the environmental impacts (e.g., CO2-emission-induced global warming potential) and energy use of the infrastructure materials and built environment. The correlation between engineering performance and environmental performance is critical to sustainability and decarbonization at scale.
Life-cycle assessment is a methodology for evaluating the environmental impacts associated with stages of the life cycle of products. For example, in the case of low-carbon concrete, environmental impacts are assessed from raw material extraction to mixing.
At LLNL, Jiaqi uses OpenLCA and Sima Pro with up-to-date databases.
Environmental impact of cement production