Application of biochar cement-based materials for carbon sequestration

•A summary of the hotspots of biochar cementitious material is provided.•The carbon sequestration mechanisms of biochar cement-based materials are analyzed.•The properties of biochar cement-based materials are introduced.•The greener capabilities of biochar cement-based materials are reviewed. In recent years, carbon emissions from cement production and agricultural waste treatment have been increasing year by year. Biochar, as a derivative of agricultural waste, provides the possibility of reducing the carbon emissions of cement-based materials. Biochar has a rich pore structure, and after being added to cement-based materials, it accelerates the hydration of cement, promotes the absorption of CO2 by cement itself, and achieves dual carbon sequestration of biochar and cement-based materials. This article summarized the latest research progress through big data analysis and interdisciplinary work, providing guidance for the research of biochar cement-based materials. The mechanical properties, workability, durability, and carbon fixation performance of biochar cement-based materials were analyzed. In addition, the synergistic mechanism of biochar and cement carbonization reaction and their impact on the carbon capture capacity of cement-based composite materials were studied. In order to better determine the application of cement-based materials in energy conservation and emission reduction, the concept of circular economy was introduced, and the total CO2 emissions and economic value of biochar cement-based materials were quantitatively studied.