Raising the solubility of Gd yields superior thermoelectric performance in n-type PbSe

Abstract

Chemical doping is an indispensable means of improving the performance of thermoelectric materials, while one bottleneck for maximizing optimization is the low solubility of dopants. Here, we report a striking...

Interfacial modulation to achieve low lattice thermal conductivity and enhanced thermoelectric performance in n-type Mg3(Sb, Bi)2-based materials via graphene and MXene

“…However, the x = 0.6 G sample shows a gradually reduced S aer 453 K, which may result from the enhanced bipolar effect. 38 To understand the increased S, we compared the n H -dependent theoretical Pisarenko curve using a single parabolic band (SPB) model 39,40 (Fig. 6(b)).…”

Enhancing the thermoelectric performance of SnTe-CuSbSe2with an ultra-low lattice thermal conductivity

“…In commercial applications, thermoelectric materials usually require excellent ZT values; therefore, strategies to improve ZT values have been constantly explored in recent years, 4 generally by means of lessening the κ L or/and boosting the power factor (PF = S 2 σ ). 5,6 Since S , σ and κ E are invariably coupled with the carrier concentration ( n ), it is thus difficult to achieve their synergistic modulation, leaving only κ L to be modulated as an independent parameter; this is particularly important for TE materials with intrinsically large κ L . 7 Therefore, creating additional phonon scattering centers to restrict heat propagation through lattice vibration and reduce the κ L is highly preferable and effective toward thermoelectric optimization.…”

Unique Semi‐Coherent Nanostructure Advancing Thermoelectrics of N‐Type PbSe

“…Therefore, the intrinsic small Seebeck coefficient can only be boosted via introducing resonant levels or flattening conduction band. [10,12,18,[45][46][47] Representative demonstrations of resonant levels in n-type thermoelectric materials include Tl-doped PbTe [17] and Al-doped PbSe. [18] Their electrical properties are generally improved at low temperatures, but the rise in temperature drives the Fermi level to gradually deviate from the resonant energy, leading to the weakening of the resonance effect, thereby hindering the improvement of thermoelectric performance at high temperatures.…”

“…[18] Their electrical properties are generally improved at low temperatures, but the rise in temperature drives the Fermi level to gradually deviate from the resonant energy, leading to the weakening of the resonance effect, thereby hindering the improvement of thermoelectric performance at high temperatures. [48] In sharp contrast, the band flattening can enhance S in the whole temperature region while effectively suppressing the bipolar diffusion for n-type PbSe, [10,12,47] making it the most promising strategy for achieving high PF.…”

“…Furthermore, the Seebeck coefficient of n‐type PbSe increases by Gd doping due to the flattened conduction band confirmed by our previous work (Figure 1a). [ 47 ] As a result, the peak zT dramatically increases by ≈50%. This study provides new guidance for improving the thermoelectrics by constructing semi‐coherent nanostructures and interface engineering.…”