Multifold enhancement of the output power of flexible thermoelectric generators made from cotton fabrics coated with conducting polymer

In this paper, we report a study on the infrared stealth properties of cotton fabrics with ZnO: (Al,In) coating. Al, In doped ZnO samples were prepared through sol-gel method. The crystalline phase of the ZnO: (Al, In) solids were determined by XRD. IR-2 Dual-Band Infrared Emissivity Measuring Instrument was used to test the infrared emissivity of the coated fabric. Infrared stealth effect of ZnO: (Al, In) coated fabric was measured using thermal infrared photospectrometry instrument. It was found that the ZnO: (Al, In) thin film has a low infrared emission in the range of 8 ~ 14μm wavelengths, and the addition of Al and In leaded to a better infrared stealth effect.

Download Full-text

An Experimental Method for Fast Evaluating Thermoelectric Generators Using one pair of P- and N-type Legs

Journal of Energy Resources Technology ◽

10.1115/1.4050574 ◽

2021 ◽

pp. 1-12

Author(s):

Ting Zhao ◽

Kewen Li ◽

Yuhao Zhu ◽

Lin Jia ◽

Xiaoyong Hou ◽

...

Keyword(s):

Experimental Method ◽

Output Power ◽

Temperature Difference ◽

Open Circuit Voltage ◽

Open Circuit ◽

Experimental Results ◽

Single Pair ◽

Thermoelectric Generators ◽

Cross Sectional ◽

Specific Temperature

Abstract Thermoelectric generators (TEG) are widely used in many industries. The voltage and output power of TEG chips are critical indicators to evaluate the performance of TEGs. The conventional method is to directly test the output voltage and power of the whole TEG chip that contains 127 pairs of PN (P- and N-type) legs (127-PN-TEG). However, the assembling of these PN legs is very time-consuming. In order to reduce experimental time and the consumption of TEG materials, we proposed an experimental method. We developed the test apparatus for the rapid evaluation of TEG performance using a TEG chip with a single pair of PN legs (1-PN-TEG). We made several 1-PN-TEGs and 127-PN-TEGs using the same thermoelectric material (bismuth telluride). We then measured the voltage and the power of these 1-PN-TEGs and 127-PN-TEGs, respectively. The experimental results were compared and analyzed. The comparison showed that the voltage of 127-PN-TEG is equal to the voltage of 1-PN-TEG times 127, which implies that we could use the test data of 1-PN-TEG to evaluate the performance of 127-PN-TEG. Using the experimental device developed in this paper, we also studied the effects of the PN leg area (cross-sectional area of PN legs) and the pressure applied over the TEGs on the output power of 1-PN-TEG. The experimental results showed that the power per unit area decreases with an increase in the 1-PN-TEG's PN leg area when the temperature difference between the hot and cold sides was constant. Under a specific temperature difference conditions, the open-circuit voltage and the output power will increase with the pressure applied on the TEG chips.

Download Full-text

Flexible film-based thermoelectric generators

MRS Advances ◽

10.1557/adv.2019.256 ◽

2019 ◽

Vol 4 (30) ◽

pp. 1691-1697

Author(s):

Shuping Lin ◽

Wei Zeng ◽

Lisha Zhang ◽

Xiaoming Tao

Keyword(s):

Seebeck Coefficient ◽

Thermoelectric Generator ◽

Low Cost ◽

Thermoelectric Generators ◽

Polystyrene Sulfonate ◽

Paper Substrate ◽

Thermoelectric Element ◽

Flexible Film ◽

P Type ◽

Flexible Thermoelectric

ABSTRACT:The present work highlights the progress in the field of flexible thermoelectric generator (f-TEGs) fabricated by 3-D printing strategy on the typing paper substrate. In this study, printable thermoelectric paste was developed. The dimension of each planer thermoelectric element is 30mm*4mm with a thickness of 50 μm for P-type Bismuth Tellurium (Bi2Te3)-based/ poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) leg. A single thermoleg with this dimension can generate a voltage of 5.38 mV at a temperature difference of 70 K. The calculated Seebeck Coefficient of a single thermoleg is 76.86 μV/K. This work demonstrates that low-cost printing technology is promising for the fabrication of f-TEGs.

Download Full-text

High-throughput physical vapour deposition flexible thermoelectric generators

Scientific Reports ◽

10.1038/s41598-019-41000-y ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 7

Author(s):

Katrina A. Morgan ◽

Tian Tang ◽

Ioannis Zeimpekis ◽

Andrea Ravagli ◽

Chris Craig ◽

...

Keyword(s):

High Throughput ◽

Vapour Deposition ◽

Thermoelectric Generators ◽

Physical Vapour Deposition ◽

Flexible Thermoelectric

Download Full-text

Evaluation and development of antibacterial fabrics using Pongamia pinnata extracts

Research Journal of Textile and Apparel ◽

10.1108/rjta-10-2018-0059 ◽

2019 ◽

Vol 23 (3) ◽

pp. 257-268

Author(s):

Swetha Andra ◽

Murugesan Muthalagu ◽

Jaison Jeevanandam ◽

Durga Devi Sekar ◽

Rajalakshmi Ramamoorthy

Keyword(s):

Antibacterial Activity ◽

Leaf Extract ◽

Tap Water ◽

Cotton Fabrics ◽

Pongamia Pinnata ◽

Root Bark ◽

Content Type ◽

Coated Fabric ◽

Soxhlet Apparatus ◽

Wash Durability

Purpose A widespread focus on the plant-based antimicrobial cotton fabric finishes has been accomplished with notable importance in recent times. The antimicrobials prevent microbial dwelling in fabrics, which causes severe infections to the fabric users. Chemical disinfectants were conventionally used in fabrics to address this challenge; however, they were found to be toxic to humans. Thus, the present study aims to deal with the utilization of phytochemical extracts from different parts of Pongamia pinnata as antimicrobial coatings in cotton fabrics. Design/methodology/approach The root, bark and stem were collected and washed several times using tap water. Then, the leaves were dried at room temperature and the root and bark were dried using an oven at 40ºC. After drying, they were ground into fine powder and extracted with ethanol using the Soxhlet apparatus. After that the extract was coated on the fabric tested for antimicrobial studies. Findings The results reported that the leaf extract of P. pinnata-coated fabric exhibited enhanced antibacterial property towards gram-negative Escherichia coli bacteria, followed by root, bark and stem. The wash durability test in the extract-coated fabric samples revealed that dip-coating retained antibacterial activity until five washes. Thus, the current study clearly suggests that the leaf extract from P. pinnata is highly useful to develop antibacterial cotton fabrics as health-care textiles. Originality/value The novelty of the present work is to obtain the crude extract from the leaves, bark, root and stem of P. pinnata and evaluate their antibacterial activity against E. coli, upon being coated on cotton fibres. In addition, the extracts were subjected to wash durability analysis to study the coating efficiency of the phytochemicals in cotton fabrics and a probable mechanism for the antibacterial activity of P. pinnata extracts was also presented.

Download Full-text