Fabrication Of Bi2te3 And PbTe Based Thermoelectric Materials Using Hot Pressed Method And Its Seebeck Coefficient Under Large Temperature Difference
Thermoelectric material is useful in converting heat waste to electricity as long there isexist of temperature difference (ΔT). Bismuth telluride (Bi2Te3) and lead telluride (PbTe) based thermoelectric (TE) materials are state-of-art materials at a low and medium temperature range of 300 – 500 K...
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Universiti Sains Islam Malaysia |
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Thermoelectric materials Electrical engineering—Materials |
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Thermoelectric materials Electrical engineering—Materials Nur Zahidah Izzati Binti Mohd Sallehin Fabrication Of Bi2te3 And PbTe Based Thermoelectric Materials Using Hot Pressed Method And Its Seebeck Coefficient Under Large Temperature Difference |
| description |
Thermoelectric material is useful in converting heat waste to electricity as long there
isexist of temperature difference (ΔT). Bismuth telluride (Bi2Te3) and lead telluride
(PbTe) based thermoelectric (TE) materials are state-of-art materials at a low and
medium temperature range of 300 – 500 K and 500 – 900 K, respectively. Seebeck
coefficient is one of the thermoelectric properties that determine its performance
through dimensionless figure-of-merit (ZT). The common fabrication method of TE
materialsis using the spark plasma sintering (SPS) under high pressure (20 to 50 MPa),
temperature (773 to 1373 K) and under the flow of current due to its high performances
output and a short time (5 to 30 minutes). However, the equipment is not available in
Malaysia. On the other hand, the measurement of Seebeck conventionally made using
a hot probe is measured under a small temperature difference (sΔT) which doesn’t
represent the real condition of operation of the material. Therefore, this study is to
investigate an alternative fabrication method using a widely available hot press
machineand study its Seebeck behaviour under large temperature differences (lΔT).
Four targettypes of samples were made using this method, which is n-Bi2Te2.7Se0.3, n PbTe0.8Se0.2,p-Bi0.3Sb1.7Te3 and p-Pb0.4Sn0.6Te. Two methods of preparation ofsample
were studied,using atomic mass and volume ratio method. In the atomic mass method,
the total molecular weight of the compound was calculated followed by the percentage
mass ofeach material to get the total density of the compound. Then, the total mass of
compoundpowder was calculated to produce the mass of each material. Meanwhile, in
the volumeratio method, the density of each material in the compound was used to
calculate the required amount of each compound. Samples were then compressed
under varied pressure, temperature and time to obtain optimization. Compositions of
samples were confirmed using the Energy Dispersive Spectroscopy (EDS) while
Seebeck and resistivity samples were measured using an in-house hot probe and 4-
point probe. This study successfully fabricated Bi2Te3 and PbTe based bulk
thermoelectric materials using the hot press method. Samples using atomic mass (AM)
calculation show the closest composition ratio of n- Bi2.2Te2.6Se0.2, p- Bi0.6Sb1.6Te2.8,
n-Pb1.1Te0.7Se0.2 and p-Pb0.7Sn0.2Te1.1 which fabricated under pressure and holding
time of 13 MPa and 17 minutes at a temperature of 423 K and 493 K respectively.
Seebeck for n-Bi2.2Te2.6Se0.2at room temperature is -53 µV/K which gives 65% lower
compared to the literature composition of Bi2Te2.7Se0.3 but n-Pb1.1Te0.7Se0.2 samples
give similar Seebeck of -249 µV/K. Similar results were obtained for both p Bi0.6Sb1.6Te2.8 and p-Pb0.5Sn0.2Te1.1 samples which shows a significant difference in
lΔT as compared to sΔT of literature. On the other hand, all samples showed slightly
higher electrical resistivity than in the literature also has been discussed. It can be
concluded that thermoelectric materials could be fabricated using the hot press method
as an alternative method at a lower cost.Although its performance is lower than the
SPS method, it could be improved by increasing the temperature, pressure and time.
The implication of this study could encourage high-performance thermoelectric
materials study in Malaysia and develop aninterest in waste heat recovery. |
| format |
Thesis |
| author |
Nur Zahidah Izzati Binti Mohd Sallehin |
| author_facet |
Nur Zahidah Izzati Binti Mohd Sallehin |
| author_sort |
Nur Zahidah Izzati Binti Mohd Sallehin |
| title |
Fabrication Of Bi2te3 And PbTe Based Thermoelectric Materials Using Hot Pressed Method And Its Seebeck Coefficient Under Large Temperature Difference |
| title_short |
Fabrication Of Bi2te3 And PbTe Based Thermoelectric Materials Using Hot Pressed Method And Its Seebeck Coefficient Under Large Temperature Difference |
| title_full |
Fabrication Of Bi2te3 And PbTe Based Thermoelectric Materials Using Hot Pressed Method And Its Seebeck Coefficient Under Large Temperature Difference |
| title_fullStr |
Fabrication Of Bi2te3 And PbTe Based Thermoelectric Materials Using Hot Pressed Method And Its Seebeck Coefficient Under Large Temperature Difference |
| title_full_unstemmed |
Fabrication Of Bi2te3 And PbTe Based Thermoelectric Materials Using Hot Pressed Method And Its Seebeck Coefficient Under Large Temperature Difference |
| title_sort |
fabrication of bi2te3 and pbte based thermoelectric materials using hot pressed method and its seebeck coefficient under large temperature difference |
| granting_institution |
Universiti Sains Islam Malaysia |
| url |
https://oarep.usim.edu.my/bitstreams/381f5c05-7210-4e36-bc79-0dc3dfc3baac/download https://oarep.usim.edu.my/bitstreams/9dbaa441-2933-4fb0-aec1-cf01bb3b95a0/download https://oarep.usim.edu.my/bitstreams/e12418de-aa5d-4fc8-a710-79a8e57f3b62/download https://oarep.usim.edu.my/bitstreams/9b08ada9-f991-46f0-8f44-ae12d0693918/download https://oarep.usim.edu.my/bitstreams/900e5a93-9c52-4205-a6b1-76c9b021edd8/download https://oarep.usim.edu.my/bitstreams/ca9bf619-c8c2-4cc9-8eaa-e1364026e17e/download https://oarep.usim.edu.my/bitstreams/19eeb4a2-1328-45ad-8b9c-dabb58ad4343/download https://oarep.usim.edu.my/bitstreams/d57882c2-9bbc-46d0-bbee-4430a4c2ac91/download |
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my-usim-ddms-125202024-05-29T18:14:50Z Fabrication Of Bi2te3 And PbTe Based Thermoelectric Materials Using Hot Pressed Method And Its Seebeck Coefficient Under Large Temperature Difference Nur Zahidah Izzati Binti Mohd Sallehin Thermoelectric material is useful in converting heat waste to electricity as long there isexist of temperature difference (ΔT). Bismuth telluride (Bi2Te3) and lead telluride (PbTe) based thermoelectric (TE) materials are state-of-art materials at a low and medium temperature range of 300 – 500 K and 500 – 900 K, respectively. Seebeck coefficient is one of the thermoelectric properties that determine its performance through dimensionless figure-of-merit (ZT). The common fabrication method of TE materialsis using the spark plasma sintering (SPS) under high pressure (20 to 50 MPa), temperature (773 to 1373 K) and under the flow of current due to its high performances output and a short time (5 to 30 minutes). However, the equipment is not available in Malaysia. On the other hand, the measurement of Seebeck conventionally made using a hot probe is measured under a small temperature difference (sΔT) which doesn’t represent the real condition of operation of the material. Therefore, this study is to investigate an alternative fabrication method using a widely available hot press machineand study its Seebeck behaviour under large temperature differences (lΔT). Four targettypes of samples were made using this method, which is n-Bi2Te2.7Se0.3, n PbTe0.8Se0.2,p-Bi0.3Sb1.7Te3 and p-Pb0.4Sn0.6Te. Two methods of preparation ofsample were studied,using atomic mass and volume ratio method. In the atomic mass method, the total molecular weight of the compound was calculated followed by the percentage mass ofeach material to get the total density of the compound. Then, the total mass of compoundpowder was calculated to produce the mass of each material. Meanwhile, in the volumeratio method, the density of each material in the compound was used to calculate the required amount of each compound. Samples were then compressed under varied pressure, temperature and time to obtain optimization. Compositions of samples were confirmed using the Energy Dispersive Spectroscopy (EDS) while Seebeck and resistivity samples were measured using an in-house hot probe and 4- point probe. This study successfully fabricated Bi2Te3 and PbTe based bulk thermoelectric materials using the hot press method. Samples using atomic mass (AM) calculation show the closest composition ratio of n- Bi2.2Te2.6Se0.2, p- Bi0.6Sb1.6Te2.8, n-Pb1.1Te0.7Se0.2 and p-Pb0.7Sn0.2Te1.1 which fabricated under pressure and holding time of 13 MPa and 17 minutes at a temperature of 423 K and 493 K respectively. Seebeck for n-Bi2.2Te2.6Se0.2at room temperature is -53 µV/K which gives 65% lower compared to the literature composition of Bi2Te2.7Se0.3 but n-Pb1.1Te0.7Se0.2 samples give similar Seebeck of -249 µV/K. Similar results were obtained for both p Bi0.6Sb1.6Te2.8 and p-Pb0.5Sn0.2Te1.1 samples which shows a significant difference in lΔT as compared to sΔT of literature. On the other hand, all samples showed slightly higher electrical resistivity than in the literature also has been discussed. It can be concluded that thermoelectric materials could be fabricated using the hot press method as an alternative method at a lower cost.Although its performance is lower than the SPS method, it could be improved by increasing the temperature, pressure and time. The implication of this study could encourage high-performance thermoelectric materials study in Malaysia and develop aninterest in waste heat recovery. Universiti Sains Islam Malaysia 2022-06 Thesis en_US https://oarep.usim.edu.my/handle/123456789/12520 https://oarep.usim.edu.my/bitstreams/5f3fac58-0d3c-4b42-86c3-304c2ec8c294/download 8a4605be74aa9ea9d79846c1fba20a33 https://oarep.usim.edu.my/bitstreams/381f5c05-7210-4e36-bc79-0dc3dfc3baac/download 6a2d528cb6a15b57c77381f128fd12ee https://oarep.usim.edu.my/bitstreams/9dbaa441-2933-4fb0-aec1-cf01bb3b95a0/download 2334de6575491f9619b8705f979e45d4 https://oarep.usim.edu.my/bitstreams/e12418de-aa5d-4fc8-a710-79a8e57f3b62/download 59651160f5cfa3ffc4d085603623f8cd https://oarep.usim.edu.my/bitstreams/9b08ada9-f991-46f0-8f44-ae12d0693918/download 7686a142dfed3d528a384bcb960d30e3 https://oarep.usim.edu.my/bitstreams/900e5a93-9c52-4205-a6b1-76c9b021edd8/download 2eaf291d5bc5fb37f288884a4c83f75d https://oarep.usim.edu.my/bitstreams/ca9bf619-c8c2-4cc9-8eaa-e1364026e17e/download 4149c98327f44fcbc43e7cfe4aba0a01 https://oarep.usim.edu.my/bitstreams/19eeb4a2-1328-45ad-8b9c-dabb58ad4343/download 4b7b6d3433f4cd3460bd059dcaef716b https://oarep.usim.edu.my/bitstreams/d57882c2-9bbc-46d0-bbee-4430a4c2ac91/download c5af7306f4b5b3acad30b789be2f8c3b https://oarep.usim.edu.my/bitstreams/74598e15-d24c-409e-ba20-d24c6e9c49aa/download 08830e0f267bd86514f18b2bbc10a292 https://oarep.usim.edu.my/bitstreams/89ae45db-e30c-4841-970a-3aac66a05c28/download 86c56c39845adb070cb6b2354591912a https://oarep.usim.edu.my/bitstreams/a223d97a-d080-41d3-8a8e-9a53a087d093/download 1548518b810983ff79fb59a9d25468bb https://oarep.usim.edu.my/bitstreams/d6ae1fd3-049e-40ab-a5d0-ee6d9de8ba03/download f7a4bdfc02068aaf7b24c990ca1d12fc https://oarep.usim.edu.my/bitstreams/da21526b-7998-416d-8f92-c1886a3e6474/download 43103eb4c405d30456ef733e3f0b6355 https://oarep.usim.edu.my/bitstreams/24291e9b-7bea-48a1-a1b4-4fac23818391/download a3631ea39730f98c78c2b38effefc1aa https://oarep.usim.edu.my/bitstreams/17be316e-f3d8-4c9a-9116-c5cdc658638d/download f5a9a49bd62c748572546f4a68dc9b11 https://oarep.usim.edu.my/bitstreams/74b14178-eacf-42c8-a7a3-32170ee137d2/download 842c3d46c0d2e96e62ae8d581a9b6f19 Thermoelectric materials Electrical engineering—Materials |