Reinspecting and offsetting lifecycle carbon with advanced materials in buildings for smart cities

A cross-scale ‘material-component-system’ framework is essential for climate change adaption, zero-carbon and Sustainable Development Goals (SDGs) of smart cities, whereas reinspecting lifecycle analysis (LCA) approach with carbon emission elimination and off-setting is highly necessary to provide stage-based quantifiable guidelines and initiatives. In this study, offsetting lifecycle carbon emissions in buildings was conducted through an innovative nano/micro/meso/macro-scale framework with cross-disciplinary mechanisms, such as electrification/hydrogenation transitions, consistent carbon database/standardization, passive/active designs, decentralised renewable unit, hybrid thermal-electrical-gas storages, advanced energy conversion and management, among others. Afterward, a reinspection of LCA approach is proposed with advanced carbon elimination and off-setting strategies (e.g., carbon capture and storage, photosynthesis conversion through tree planting and afforestation). Fundamental roles, underlying mechanisms and priority sequence of each strategy in carbon-neutrality are specifically quantified, together with bottlenecks and challenges. Finally, a roadmap, and initiatives and policy actions are provided in the building sectors and the entire energy supply chain in China, with carbon-positive and carbon-negative strategies for carbon neutrality in China by 2060.