First-principles investigation of MXenes M4C3 (M = Sc, Cr, and Mn) for clean energy

This study explores the characteristics of M4C3 (M = Sc, Cr, and Mn) MXenes. We investigate their structural, thermoelectric, and optoelectronic properties to assess their potential applications in clean energy technologies. Our analysis reveals that these carbides exhibit varying phase stabilities, with the following sequence: Sc4C3 > Cr4C3 > Mn4C3. Notably, Sc4C3 displays a band gap of 0.784 eV in mBJ-GGA, while Cr4C3 and Mn4C3 exhibit metallic properties in their band gaps. These findings are based on density functional theory (DFT) calculations using the Wien2k code. We conducted stability tests and found that Sc4C3 exhibits stability. Using the BoltzTraP2 code, the transport properties were thoroughly investigated in terms of electrical conductivity, thermal conductivity, and Seebeck coefficient. The increase in the ZT number of Sc4C3 from 0.05 to 0.62 as a function of temperature confirms its suitability for infrared light-operated devices rather than thermoelectric applications. This significant enhancement of the figure of merit (ZT) for Sc4C3 also underscores its potential role in clean energy applications. Overall, our results provide valuable insights into the potential of these materials for clean energy applications.