Thermoelectric properties of two-dimensional double transition metal MXenes: ScYCT2 (T=F, OH)

Using first-principles calculations, we research the stability and electronic properties of two-dimensional double transition metal MXenes ScYCT2 (T=F, OH). On this basis, the semiconductor properties of ScYCF2 and ScYC(OH)2 are determined, and their thermoelectric properties are investigated by using Boltzmann transport theory and Slack model. The results show that the investigated MXenes structures have high thermoelectric properties. In particular, the n-type ScYC(OH)2 has the largest power factor of 0.072 W/mK2 at 900 K, and its maximum ZT value exceeds 3. According to the calculation result, we predict the ZT values for both the ScYCF2 and ScYC(OH)2 are greater than 1 at 900 K. The results of this study show that ScYCF2 and ScYC(OH)2 have potential as thermoelectric materials in the range of 300-900 K. And this work provides theoretical support for the experimental study of ScYCF2 and ScYC(OH)2.