materials may enhance thermoelectric efficiency, due to the sharp-peaked electronic density of states (DOS) in low-dimensional materials [@Dresselhausprb47-93-1; @Bilc]. The Seebeck coefficient, which depends on logarithmic derivative of DOS, is significantly enhanced in 2D materials and hence, the thermoelectric efficiency increases  [@Mahan]. This seminal work of the thermoelectric materials could be an important starting point for today’s achievements. Due to the decreased thermal conductivity caused by phonon boundary scattering and consequently, improved figure of merit on quantum confinements in low dimensional systems, ${\it ZT}$ values become dramatically larger than the corresponding bulk materials.

Using energy filtering proposal, the Seebeck coefficient increases by introducing a strongly energy-dependent scattering mechanism  [@Mahan; @Neophytou; @Fomin; @Zianni]. Other useful methods are also used for enhancing thermoelectric performance. The use of band structure engineering [@Heremanssci08; @Liu-Zhao-APL08] in conjunction with nanostructuring, to lower the thermal conductivity, could further enhance figure of merit of thermoelectric materials. It is known that quantum confinement of carriers in bulk samples, containing nanostructured constituents [@Dresselhaus07], quantum-well super-lattices  [@Dresselhausprb47-93-1], as well as quantum-wires [@Dresselhausprb47-93-2], will enhance thermoelectric efficiency in order to promote the more widespread use of thermoelectric materials.

According to a comprehensive review on the thermoelectric materials [@Xiao-npj18], among the well-known thermoelectric 