The high thermopower of the Zintl compound Sr5Sn2As6 over a wide temperature range: first-principles calculations

By using first principles calculations, we propose a codoping method of using acceptors and donors simultaneously to realize low-resistivity and high carrier concentration p-type ZnS with wurtzite structure. The ionization energy of singleNScan be lowered by introducing theIIIZn-NS(III = Al, Ga, In) passivation system. Codoping method in ZnS (2N, III) has lower formation energy comparing with single doping of N since III elements act as reactive codopants.

Download Full-text

Strain Engineered Band Gaps and Electronic Properties in PbPdO2 and PbPd0.75Co0.25O2 Slabs

Materials ◽

10.3390/ma11102002 ◽

2018 ◽

Vol 11 (10) ◽

pp. 2002

Author(s):

Yanmin Yang ◽

Kehua Zhong ◽

Guigui Xu ◽

Jian-Min Zhang ◽

Zhigao Huang

Keyword(s):

Electronic Structure ◽

Carrier Concentration ◽

First Principles ◽

Bond Angle ◽

Charge Carrier Concentration ◽

Band Gaps ◽

First Principles Calculations ◽

Potential Mechanism ◽

Plane Anisotropy ◽

External Strain

Electronic structure and corresponding electrical properties of PbPdO2 and PbPd0.75Co0.25O2 ultrathin slabs with (002) preferred orientation were systematically investigated using first-principles calculations. The calculated results revealed the strain induced evidently the changes of band structure and carrier concentration in both slabs. It was also found that PbPdO2 and PbPd0.75Co0.25O2 ultrathin slabs exhibited evident differences in the external strain dependence of the band gap and charge carrier concentration, which was strongly dependent on bond angle and bond length induced by in-plane anisotropy strain. Interestingly, the carrier concentration of the PbPd0.75Co0.25O2 slab could increase up to 5–6 orders of magnitude with the help of external strain, which could explain the potential mechanism behind the observed colossal strain-induced electrical behaviors. This work demonstrated that the influence of the doping effect in the case of PbPdO2 could be a potentially fruitful approach for the development of promising piezoresistive materials.

Download Full-text

Unusually High Seebeck Coefficient Arisen from the Temperature-dependent Carrier Concentration in PbSe-AgSbSe2 Alloys

Journal of Materials Chemistry C ◽

10.1039/d1tc04158d ◽

2021 ◽

Author(s):

Xuemei Wang ◽

Gang Wu ◽

Jianfeng Cai ◽

Qiang Zhang ◽

Junxuan Yang ◽

...

Keyword(s):

Temperature Gradient ◽

Seebeck Coefficient ◽

Carrier Concentration ◽

Wide Temperature Range ◽

Induced Voltage ◽

Temperature Dependent ◽

Temperature Range ◽

High Seebeck Coefficient

Seebeck coefficient describes the temperature gradient induced voltage in thermoelectrics. Usually, to obtain a high Seebeck coefficient within a wide temperature range is difficult, as it is limited by the...

Download Full-text

Temperature-Driven Phase Transition and Transition Dipole Moment of Two-Dimensional (BA)2CsPb2Br7 Perovskite

Physical Chemistry Chemical Physics ◽

10.1039/d1cp01941d ◽

2021 ◽

Author(s):

Jia Lin ◽

Yajing Wang ◽

Qilin Song ◽

Wenjing Hu ◽

Dan Wang ◽

...

Keyword(s):

Phase Transition ◽

Dipole Moment ◽

First Principles ◽

Transition Dipole Moment ◽

Two Dimensional ◽

First Principles Calculations ◽

Transition Dipole ◽

Temperature Range ◽

Halide Perovskite

The structures of hybrid two-dimensional (2D) Ruddlesden-Popper (RP) phase layered halide perovskite (BA)2CsPb2Br7 in the temperature range of 100 to 450 K were constructed and systematically investigated by first-principles calculations....

Download Full-text