Multi-cations compound Cu2CoSnS4: DFT calculating, band engineering and thermoelectric performance regulation

Combination of Carrier Concentration Regulation and High Band Degeneracy for Enhanced Thermoelectric Performance of Cu3SbSe4

“…Consequently, the power factor has greatly improved in the wide temperature region (Figure c) for the Ga-doped samples and the maximum one is up to 1312.73 μW m –1 K –2 ; however, its enhancement starts to decline when x (Ga) is above 0.005 mainly due to the diminution of S from the split of the degenerate bands at higher doping concentration (Figure c). As described in Figure d, the thermal conductivity (κ) decreases slightly after Ga-doping, and the lattice thermal conductivity (κ L ) obtained by subtracting the carrier contribution κ e from κ was also presented in Figure e, where κ e is estimated using the Wiedemann–Franz law as done in our previous work. , One can observe that κ L decreases after doping with Ga due to the increased point-defects scattering of phonons, and it agrees with the relationship of κ L ∝ 1/ T , which suggests that the dominant scattering in phonon transport is the acoustic phonon–phonon Umklapp scattering. Finally, a peak ZT value of 0.90 at 623 K is achieved for the x (Ga) = 0.15 sample, which is about 80% higher than that of pristine Cu 3 SbSe 4 .…”

“…As described in Figure 5d, the thermal conductivity (κ) decreases slightly after Ga-doping, and the lattice thermal conductivity (κ L ) obtained by subtracting the carrier contribution κ e from κ was also presented in Figure 5e, where κ e is estimated using the Wiedemann−Franz law as done in our previous work. 12,29 One can observe that κ L decreases after doping with Ga due to the increased point-defects scattering of phonons, and it agrees with the relationship of κ L ∝ 1/T, which suggests that the dominant scattering in phonon transport is the acoustic phonon−phonon Umklapp scattering. Finally, a peak ZT value of 0.90 at 623 K is achieved for the x(Ga) = 0.15 sample, which is about 80% higher than that of pristine Cu 3 SbSe 4 .…”

Realizing high thermoelectric performance in Cu2Te alloyed Cu1.15In2.29Te4

“…The IB is critical for the transport of carriers, and it serves as the conducting pathway for holes in the p-type semiconductors, rstly from the VB to the IB, and subsequently to the CB (VB / IB / CB). 43,44…”

Understanding Cu incorporation in the Cu2xHg2−xGeTe4 structure using resonant x-ray diffraction

“…Controlling carrier concentration in the DLS family of materials via manipulation of defects and dopants has been the topic of a number of previous studies [9][10][11][12][13][14][15][16][17][18][19][20]. Our previous work revealed the existence of a full solid solution between Cu 2 HgGeTe 4 and Hg 2 GeTe 4 , denoted here as Cu 2x Hg 2−x GeTe 4 (where 0 ≤ x ≤ 1) [21].…”