n-Type PVP/SWCNT Composite Films with Improved Stability for Thermoelectric Power Generation.

Single-walled carbon nanotubes (SWCNTs) are one of the promising thermoelectric materials in applications of powering wearable electronics. However, the electrical performance of n-type SWCNTs quickly decreases in air, showing a low stability, and low-cost and effective solutions to improving its stability are also lacking, all of which limit practical applications. In this study, we studied the stability of PVP/SWCNT composite films, where oxygen and moisture from air should be responsible for the decreased stability due to oxidation and hydration. In this case, we found that coating with a 0.20 g mL-1 PVP/0.002 g mL-1 PVDF layer on the surface of PVP/SWCNTs can prevent the penetration of oxygen and moisture from air, improving film stability, where there is almost no reduction in thermoelectric performance after they are exposed to air for 60 days. Based on the stable n-type PVP/SWCNT films, a thermoelectric generator was fabricated, where poly(dimethylsiloxane) (PDMS) was used to coat the surface of the thermoelectric leg to further improve its stability. This generator showed high output performance, which achieved an open-circuit voltage of 10.6 mV and a power density of 312.2 μW cm-2 at a temperature difference of 50 K. Particularly, it exhibited high stability, where the output performance kept almost unchanged after exposure to high-humidity air for 30 days. This coating technology is also applicable to other air-sensitive materials and promotes the development and application of thermoelectric materials and devices.

[1]  Y. Liu,et al.  High-performance integrated chip-level thermoelectric device for power generation and microflow detection , 2023, Nano Energy.

[2]  Zhenhua Wu,et al.  An Emerging Energy Technology: Self‐Uninterrupted Electricity Power Harvesting from the Sun and Cold Space , 2023, Advanced Energy Materials.

[3]  D. Suzuki,et al.  Outstanding Robust Photo- and Thermo-Electric Applications with Stabilized n-Doped Carbon Nanotubes by Parylene Coating , 2023, ACS applied materials & interfaces.

[4]  Z. Ren,et al.  Improving thermal stability and revealing physical mechanism in n-type Mg3Sb2-Bi for practical applications , 2023, Nano Energy.

[5]  G. Lu,et al.  Harvesting waste heat with flexible Bi_2Te_3 thermoelectric thin film , 2022, Nature Sustainability.

[6]  Huijun Liao,et al.  Thermoelectric performance of (AgBiTe2)1-x(SnTe)x with stable cubic enabled by enhanced configurational entropy , 2022, Rare Metals.

[7]  Z. Ren,et al.  New insights into the effect of chemical bonding strength on thermoelectric performance and stability in YbMg2Bi2 toward practical thermoelectric applications , 2022, Materials Today Physics.

[8]  L. Hultman,et al.  A step-by-step guide to perform x-ray photoelectron spectroscopy , 2022, Journal of Applied Physics.

[9]  T. Zhu,et al.  Improved thermoelectric properties of zone-melted p-type bismuth-telluride-based alloys for power generation , 2022, Rare Metals.

[10]  Xianghua Zhang,et al.  Novel Thermal Diffusion Temperature Engineering Leading to High Thermoelectric Performance in Bi2Te3‐Based Flexible Thin‐Films , 2021, Advanced science.

[11]  Zhiyu Hu,et al.  Thermoelectric converter: Strategies from materials to device application , 2021, Nano Energy.

[12]  S. Yonezawa,et al.  Air stability of n-type single-walled carbon nanotube films with anionic surfactants investigated using molecular dynamics , 2021 .

[13]  Jie Chen,et al.  Low lattice thermal conductivity and enhanced thermoelectric performance of SnTe via chemical electroless plating of Ag , 2021, Rare Metals.

[14]  Fusheng Liu,et al.  N-Type Flexible Films and a Thermoelectric Generator of Single-Walled Carbon Nanotube-Grafted Tin Selenide Nanocrystal Composites. , 2021, ACS applied materials & interfaces.

[15]  Lei Wang,et al.  Oxygen-Rich Polymer Polyethylene Glycol-Functionalized Single-Walled Carbon Nanotubes Toward Air-Stable n-Type Thermoelectric Materials. , 2021, ACS applied materials & interfaces.

[16]  K. Cai,et al.  High Power Factor Ag/Ag2Se Composite Films for Flexible Thermoelectric Generators. , 2021, ACS applied materials & interfaces.

[17]  Yuanhua Lin,et al.  Flexible Thermoelectric Films Based on Bi2Te3 Nanosheets and Carbon Nanotube Network with High n-Type Performance. , 2021, ACS applied materials & interfaces.

[18]  Qingbiao Li,et al.  A novel PVDF-TiO2@g-C3N4 composite electrospun fiber for efficient photocatalytic degradation of tetracycline under visible light irradiation. , 2020, Ecotoxicology and environmental safety.

[19]  D. Pavliňák,et al.  Surface plasma treatment of the electrospun TiO2/PVP composite fibers in different atmospheres , 2020 .

[20]  K. Cai,et al.  Ultrahigh performance of n-type Ag2Se film for flexible thermoelectric power generators. , 2020, ACS applied materials & interfaces.

[21]  Liye Xiao,et al.  High-performance Ag-modified Bi0.5Sb1.5Te3 films for the flexible thermoelectric generator. , 2020, ACS applied materials & interfaces.

[22]  Jingkun Xu,et al.  Effect of Functional Groups on the Thermoelectric Performance of Carbon Nanotubes , 2019, Journal of Electronic Materials.

[23]  T. Fujigaya,et al.  Air-Stable n-Type Single-Walled Carbon Nanotubes Doped with Benzimidazole Derivatives for Thermoelectric Conversion and Their Air-Stable Mechanism , 2019, ACS Applied Nano Materials.

[24]  Lei Wang,et al.  High-performance n-type carbon nanotubes composites: Improved power factor by optimizing the acridine scaffold and tailoring the side chains. , 2019, ACS applied materials & interfaces.

[25]  J. E. Martín-Alfonso,et al.  Development and characterization of composite fibers based on tragacanth gum and polyvinylpyrrolidone , 2019, Composites Part B: Engineering.

[26]  J. Holmes,et al.  Comparing Thermal and Chemical Removal of Nanoparticle Stabilizing Ligands: Effect on Catalytic Activity and Stability , 2018, ACS Applied Nano Materials.

[27]  J. Grunlan,et al.  Carbon‐Nanotube‐Based Thermoelectric Materials and Devices , 2018, Advanced materials.

[28]  T. Kawai,et al.  Simple Salt‐Coordinated n‐Type Nanocarbon Materials Stable in Air , 2016 .

[29]  Michael Schmidt,et al.  Stability, oxidation and shape evolution of PVP-capped Pd nanocrystals , 2014 .

[30]  Choongho Yu,et al.  Flexible power fabrics made of carbon nanotubes for harvesting thermoelectricity. , 2014, ACS nano.

[31]  S. Roth,et al.  Increasing the thermoelectric power generated by composite films using chemically functionalized single-walled carbon nanotubes , 2013 .

[32]  C. Perkins,et al.  Role of dopants in long-range charge carrier transport for p-type and n-type graphene transparent conducting thin films. , 2013, ACS nano.

[33]  Jun Zhang,et al.  Investigation on crystallization behavior and hydrophilicity of poly(vinylidene fluoride)/poly(methyl methacrylate)/poly(vinyl pyrrolidone) ternary blends by solution casting , 2013 .

[34]  Choongho Yu,et al.  N-Type Thermoelectric Performance of Functionalized Carbon Nanotube-Filled Polymer Composites , 2012, PloS one.

[35]  Choongho Yu,et al.  Air-stable fabric thermoelectric modules made of N- and P-type carbon nanotubes , 2012 .

[36]  Yunsheng Ma,et al.  Size-dependent interaction of the poly(N-vinyl-2-pyrrolidone) capping ligand with Pd nanocrystals. , 2012, Langmuir : the ACS journal of surfaces and colloids.

[37]  Lian-Feng Chu,et al.  Evolution of the precipitation kinetics, morphologies, permeation performances, and crystallization behaviors of polyvinylidenefluoride (PVDF) hollow fiber membrane by adding different molecular weight polyvinylpyrrolidone (PVP) , 2011 .

[38]  G. Teeter,et al.  n-Type transparent conducting films of small molecule and polymer amine doped single-walled carbon nanotubes. , 2011, ACS nano.

[39]  C. Nordling,et al.  Electron Spectroscopy and Chemical Binding , 1966, Nature.