This project will develop innovative and sustainable technology for complete recycling of concrete waste, including recycled concrete aggregates and recycled concrete fines, to produce carbon-negative geopolymer concrete. The successful completion of this project will promote complete recycling of concrete waste in an environmentally friendly and sustainable way to avoid the use of energy-intensive and high-carbon-footprint. It will also save on monetary and environmental costs related to transportation and disposal of concrete waste, reduce the demand for using natural sand and aggregate, and sequester carbon dioxide. Additional societal benefits will be realized through outreach and educational activities including Summer Engineering Academy and K-12 mentoring programs, development and display of educational exhibits at Biosphere 2, and mentorship of undergraduate and graduate students. The approach of this project is based on the innovative integration of carbonation and geopolymerization, which could fundamentally revolutionize the conventional concept for recycling concrete waste. The research is guided by four hypotheses. These hypotheses address the fundamental mechanisms for complete recycling concrete waste to produce carbon-negative geopolymer concrete. To test them, the project will pursue four research objectives. They include elucidating how the carbonation of recycled concrete fines affects the geopolymerization process and enhance the geopolymer properties,