Solution-processed two-dimensional layered heterostructure thin-film with optimized thermoelectric performance

Doping Sn into the Cu2Te lattice can synergistically enhance the power factor and decrease thermal conductivity, leading to remarkably optimized zTs. The lone pair electrons from the 5s orbital of Sn can increase the DOS near the Fermi level of Cu2Te to promote PF and reduce κe by decreasing the carrier concentration. This study explores a scalable strategy to optimize the thermoelectric performance for intrinsically highly degenerate semiconductors.

Download Full-text

Improving the photocurrent of a PBDTTT-CF and PCBM based organic thin film photoconductor by forming a bilayer structure

RSC Advances ◽

10.1039/c5ra16998d ◽

2015 ◽

Vol 5 (103) ◽

pp. 84680-84684 ◽

Cited By ~ 4

Author(s):

Zhiwen Jin ◽

Qing Zhou ◽

Peng Mao ◽

Aiji Wang ◽

Boyang Shang ◽

...

Keyword(s):

Thin Film ◽

Carrier Transport ◽

Fabrication Process ◽

Bilayer Structure ◽

Organic Thin Film ◽

Solution Processed

By controlling and adjusting the fabrication process, all-solution-processed bilayer OTFPs exhibits a faster carrier transport which greatly enhanced the photocurrent.

Download Full-text

Carrier dilution in TiSe2 based intergrowth compounds for enhanced thermoelectric performance

Journal of Materials Chemistry C ◽

10.1039/c5tc01570g ◽

2015 ◽

Vol 3 (40) ◽

pp. 10451-10458 ◽

Cited By ~ 13

Author(s):

S. R. Bauers ◽

D. R. Merrill ◽

D. B. Moore ◽

D. C. Johnson

Keyword(s):

Thin Film ◽

Electrical Properties ◽

Seebeck Coefficient ◽

Thermoelectric Power ◽

Power Factor ◽

Thermoelectric Performance ◽

Thermoelectric Power Factor

Synthesis and electrical properties of kinetically stabilized (PbSe)1+δ(TiSe2)n thin-film intergrowths are reported for 1 ≤ n ≤ 18. The carriers donated to the TiSe2 from PbSe are diluted with increasing n, leading to a systematic increase in the Seebeck coefficient and thermoelectric power factor.

Download Full-text

Enormous thermoelectric power factor of ZrTe2/SrTiO3 heterostructure

10.21203/rs.3.rs-89694/v1 ◽

2021 ◽

Author(s):

Chun Hung Suen ◽

Songhua Cai ◽

Hui Li ◽

Xiaodan Tang ◽

Huichao Wang ◽

...

Keyword(s):

Thin Film ◽

Thermoelectric Power ◽

Power Factor ◽

High Performance ◽

Transition Metal Dichalcogenides ◽

Thermoelectric Device ◽

Two Dimensional ◽

Dimensional Electron ◽

Thermoelectric Power Factor ◽

Dimensional Electron Gas

Abstract Achieving high thermoelectric power factor in thin film heterostructures is essential for integrated and miniaturized thermoelectric device applications. In this work, we demonstrate a mechanism to enhance thermoelectric power factor through coupling the interfacial confined two-dimensional electron gas (2DEG) with thin film conductivity in a transition metal dichalcogenides-SrTiO3 heterostructure. Owing to the formed conductive interface with two-dimensional electron confinement effect and the elevated conductivity, the ZrTe2/SrTiO3 (STO) heterostructure presents enormous thermoelectric power factor as high as 4×10^5 μW cm^(-1) K^(-2) at 20 K and 4800 μW cm^(-1) K^(-2) at room temperature. Interfacial reaction induced degradation of Ti cations valence number from Ti4+ to Ti3+ is attributed to be responsible for the formation of the quasi-two-dimensional electrons at the interface which results in very large Seebeck coefficient; and the enhanced electrical conductivity is suggested to be originated from the charge transfer induced doping in the ZrTe2. By taking the thermal conductivity of STO substrate as a reference, the effective zT value of this heterostructure can reach 15 at 300 K. This superior thermoelectric property makes this heterostructure a promising candidate for future thermoelectric device, and more importantly, paves a new pathway to design promising high-performance thermoelectric systems.

Download Full-text

High performance of solution-processed SnO2 thin-film transistors by promotion of photo-exposure time-dependent carrier transport during the pre-annealing stage

Semiconductor Science and Technology ◽

10.1088/1361-6641/ab8537 ◽

2020 ◽

Vol 35 (6) ◽

pp. 065019

Author(s):

Jun-Ik Park ◽

Do-Kyung Kim ◽

Hyunjae Lee ◽

Jaewon Jang ◽

Jihwan Park ◽

...

Keyword(s):

Thin Film ◽

Exposure Time ◽

Thin Film Transistors ◽

High Performance ◽

Carrier Transport ◽

Time Dependent ◽

Sno2 Thin Film ◽

Solution Processed ◽

Annealing Stage

Download Full-text

Electrochemical doping engineering tuning of the thermoelectric performance of a π-conjugated free-standing poly(thiophene-furan) thin-film

Materials Chemistry Frontiers ◽

10.1039/c9qm00542k ◽

2020 ◽

Vol 4 (2) ◽

pp. 597-604 ◽

Cited By ~ 3

Author(s):

Wenqian Yao ◽

Lanlan Shen ◽

Peipei Liu ◽

Congcong Liu ◽

Jingkun Xu ◽

...

Keyword(s):

Thin Film ◽

Thermoelectric Power ◽

Power Factor ◽

Thermoelectric Performance ◽

Free Standing ◽

Thermoelectric Power Factor ◽

Electrochemical Doping

Promising free-standing poly(thiophene-furan) gains a high thermoelectric power factor by facile electrochemical doping engineering.

Download Full-text

Excellent thermoelectric performance of ZrTe2 thin films and device

10.21203/rs.3.rs-141752/v1 ◽

2021 ◽

Author(s):

Chun Hung Suen ◽

Songhua Cai ◽

Hui Li ◽

Long Zhang ◽

Kunya Yang ◽

...

Keyword(s):

Thin Film ◽

Thermoelectric Power ◽

Power Factor ◽

High Performance ◽

Transition Metal Dichalcogenides ◽

Thermoelectric Device ◽

Two Dimensional ◽

Dimensional Electron ◽

Thermoelectric Power Factor ◽

Dimensional Electron Gas

Abstract Achieving high thermoelectric power factor in thin film heterostructures is essential for integrated and miniatured thermoelectric device applications. In this work, we demonstrate a mechanism and device performance of enhanced thermoelectric power factor through coupling the interfacial confined two-dimensional electron gas (2DEG) with thin film conductivity in a transition metal dichalcogenides-SrTiO3 heterostructure. Owing to the formed conductive interface with two-dimensional electron confinement effect and the elevated conductivity, the ZrTe2/SrTiO3 (STO) heterostructure presents enormous thermoelectric power factor as high as 4×10^5 μW/cmK^2 at 20 K and 4800 μW/cmK^2 at room temperature. Formation of quasi-two-dimensional electrons gas at the interface is attributed to the giant Seebeck coefficient, and enhanced electrical conductivity is suggested to be originated from charge transfer induced doping in the ZrTe2, which leads to extremely large thermoelectric power factor. By taking the thermal conductivity of STO substrate as a reference, the effective zT value of this heterostructure can reach 1.5 at 300 K. This high thermoelectric figure of merit is demonstrated by a prototype device based on this heterostructure which results in 3K temperature cooling by passing through a current of 100 mA. This superior thermoelectric property makes this heterostructure a promising candidate for future thermoelectric device, and more importantly, paves a new pathway to design promising high-performance thermoelectric systems.

Download Full-text

Minority carrier decay length extraction from scanning photocurrent profiles in two-dimensional carrier transport structures

Scientific Reports ◽

10.1038/s41598-021-01446-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Yu-Chien Wei ◽

Cheng-Hao Chu ◽

Ming-Hua Mao

Keyword(s):

Thin Film ◽

Analytical Model ◽

Carrier Transport ◽

Minority Carrier ◽

Diffusion Length ◽

Schottky Contact ◽

Decay Length ◽

Two Dimensional ◽

Decay Function ◽

Simulation Results

AbstractCarrier transport was studied both numerically and experimentally using scanning photocurrent microscopy (SPCM) in two-dimensional (2D) transport structures, where the structure size in the third dimension is much smaller than the diffusion length and electrodes cover the whole terminal on both sides. Originally, one would expect that with increasing width in 2D transport structures, scanning photocurrent profiles will gradually deviate from those of the ideal one-dimensional (1D) transport structure. However, the scanning photocurrent simulation results surprisingly showed almost identical profiles from structures with different widths. In order to clarify this phenomenon, we observed the spatial distribution of carriers. The simulation results indicate that the integrated carrier distribution in the 2D transport structures with finite width can be well described by a simple-exponential-decay function with the carrier decay length as the fitting parameter, just like in the 1D transport structures. For ohmic-contact 2D transport structures, the feasibility of the fitting formula from our previous 1D analytical model was confirmed. On the other hand, the application of a simple-exponential-decay function in scanning photocurrent profiles for the diffusion length extraction in Schottky-contact 2D transport structures was also justified. Furthermore, our simulation results demonstrate that the scanning photocurrent profiles in the ohmic- or Schottky-contact three-dimensional (3D) transport structures with electrodes covering the whole terminal on both sides will reduce to those described by the corresponding 1D fitting formulae. Finally, experimental SPCM on a p-type InGaAs air-bridge two-terminal thin-film device was carried out. The measured photocurrent profiles can be well fitted by the specific fitting formula derived from our previous 1D analytical model and the extracted electron mobility-lifetime product of this thin-film device is 6.6 × 10–7 cm2·V−1. This study allows us to extract the minority carrier decay length and to obtain the mobility-lifetime product which can be used to evaluate the performance of 2D carrier transport devices.

Download Full-text