Enhancing thermoelectric performance in carbon fiber-reinforced cement composites through boron doping

Abstract

Although carbon fiber-reinforced cements (CFRCs) have the potential for ambient energy harvesting, their low thermoelectric performance restricts their practical application in construction. In this study, we investigate the possibility of using boron doped carbon fibers to improve the thermoelectric performance of cement composites. The electrical conductivity of a single carbon fiber was significantly enhanced, reaching a value of 272.1 × 102 S/cm despite the limited amount of boron doping. This was due to the formation of highly aligned, dense, thin, and long domains within the carbon fibers, which facilitated electron flow. The pristine carbon fiber's hydrophilic surface retarded the hydration reaction, while the boron-doped carbon fiber's hydrophobic surface had a diminished impact on the hydration products. The highest power factor of 0.02 μW/mK2 in cement composites was attained by incorporating boron doped carbon fibers, which exhibit outstanding electrical conductivity, into the cement matrix.