Compared with traditional cement-based materials,cement matrix reinforced by functional fillers can not only have improved mechanical and physical properties and durability,but also obtain thermoelectric attributes. Such attributes can convert thermal heat into electric energy and vice versa,which have demonstrated great potential in the application for structural health monitoring,energy collection and de-icing. With the initiate of carbon peaking and carbon neutrality goals,thermoelectric cement-based composites (TECCs)have been attracting extensive attention from academic and industrial communities. Such TECC materials can generate electricity while reducing temperature of structural surfaces and alleviating the so-called urban island effect. With the potential of improving the structure of energy supply in urban areas,TECC has been emerging as one of the most promising construction material candidates for future. Recently,researchers have conducted extensive work to improve the thermoelectric performances of TECC through adding different fillers and employing various preparation processes and dispersion methods. The results obtained suggest that the type and the content of functional fillers are the major factors affecting the thermoelectric properties of TECC,followed by preparation process and dispersion method. Among the work conducted,the highest Seebeck coefficient of TECC was achieved by adding nano metal oxide into cement matrix. The value is two orders of magnitude larger when compared to nano carbon fillers. However,the TECC with nano carbon fillers has higher ZT value and electrical conductivity. Alternatively,some researchers dispersed metal fillers (including their oxides)and nano carbon filler into cement-based materials,and achieved significant improved thermoelectric performances with balance between Seebeck coefficient and ZT value. The highest ZT value is 0. 01 at 70 ℃,and the energy conversion efficiency is 0. 24%,which is sufficient to supply energy for low-power electronic devices such as structural health monitoring sensors. However,the current development of TECC is still facing great challenges and critical issues,particularly for large-scale application in practical engineering. Enhancing the thermoelectric properties and the performances of TECC while keeping its competitive mechanical properties has become the research focus recently. In this paper,the principle of the thermoelectric effect of cement-based composites is presented. Then the effects of different preparation processes and dispersion methods on the thermoelectric properties of TECC are discussed. The methods for characterizing and measuring the thermoelectric properties are summarized. The effects of various functional fillers on the thermoelectric properties of cement-based composites are elaborated,and the potential application of TECC in practical engineering is envisaged. This review also proposes some challenges and problems to be solved for further development of thermoelectric cement-based materials. Moreover,the paper proposes some directions for theoretical modelling and experimental work,in order to provide guidelines for developing TECC with good dispersion of functional fillers and excellent thermoelectric properties. © 2023 Cailiao Daobaoshe/ Materials Review. All rights reserved.
