Enhanced catalytic palladium embedded inside porous silicon for improved hydrogen gas sensing

In this work, we reported on room temperature porous silicon (PS) and embedding PS using simple and economical techniques of electrochemical etching and thermal evaporation. The PS substrate was prepared using the technique of electrochemically etching the n-type Si (100) wafer at a constant current...

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Main Authors: Alhan Farhanah Abd Rahim, Nurul Syuhadah Mohd Razali, Rosfariza Radzali, Ainokhilah Mahmood, Irni Hamiza Hamzah, Mohamed Fauzi Packeer Mohamed
Format: Article
Language:English
Published: Penerbit Universiti Kebangsaan Malaysia 2022
Online Access:http://journalarticle.ukm.my/21209/
http://journalarticle.ukm.my/21209/1/SDB%2017.pdf
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author Alhan Farhanah Abd Rahim,
Nurul Syuhadah Mohd Razali,
Rosfariza Radzali,
Ainokhilah Mahmood,
Irni Hamiza Hamzah,
Mohamed Fauzi Packeer Mohamed,
author_facet Alhan Farhanah Abd Rahim,
Nurul Syuhadah Mohd Razali,
Rosfariza Radzali,
Ainokhilah Mahmood,
Irni Hamiza Hamzah,
Mohamed Fauzi Packeer Mohamed,
author_sort Alhan Farhanah Abd Rahim,
building UKM Institutional Repository
collection Online Access
description In this work, we reported on room temperature porous silicon (PS) and embedding PS using simple and economical techniques of electrochemical etching and thermal evaporation. The PS substrate was prepared using the technique of electrochemically etching the n-type Si (100) wafer at a constant current density of 10 mA/cm2 for 10 min under the illumination of incandescent white light. After PS formation, Ge pieces were thermally evaporated onto the two PS substrates in a vacuum condition. This was then followed by the deposition of the ZnO layer onto the Ge/PS substrate by the same method using commercial 99.9% pure ZnO powders. The three samples were identified as PS, Ge/PS and ZnO/Ge/PS samples, respectively. Pd finger contacts were deposited on the PS and embedding PS (Ge/PS and ZnO/Ge/PS) to form Pd on PS hydrogen sensors using RF magnetron sputtering. SEM and EDX suggested the presence of substantial Ge and ZnO inside the uniform circular pores for Ge/PS and ZnO/Ge/PS samples, respectively. Raman spectra showed that good crystalline Ge and ZnO nanostructures embedded inside the pores were obtained. For hydrogen sensing, Pd on ZnO/Ge/PS Schottky diode exhibited a dramatic change of current after exposure to H2 as compared to PS and Ge/PS devices. It is observed that the sensitivity increased exponentially with the hydrogen flow rate for all the sensors. The ZnO/Ge/PS showed more sensitivity towards H2 than that of PS and Ge/PS especially at high flow rate of H2 with higher current gain (69.11) and shorter response (180 s) and recovery times (30 s).
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spelling oai:generic.eprints.org:212092023-02-27T08:50:08Z http://journalarticle.ukm.my/21209/ Enhanced catalytic palladium embedded inside porous silicon for improved hydrogen gas sensing Alhan Farhanah Abd Rahim, Nurul Syuhadah Mohd Razali, Rosfariza Radzali, Ainokhilah Mahmood, Irni Hamiza Hamzah, Mohamed Fauzi Packeer Mohamed, In this work, we reported on room temperature porous silicon (PS) and embedding PS using simple and economical techniques of electrochemical etching and thermal evaporation. The PS substrate was prepared using the technique of electrochemically etching the n-type Si (100) wafer at a constant current density of 10 mA/cm2 for 10 min under the illumination of incandescent white light. After PS formation, Ge pieces were thermally evaporated onto the two PS substrates in a vacuum condition. This was then followed by the deposition of the ZnO layer onto the Ge/PS substrate by the same method using commercial 99.9% pure ZnO powders. The three samples were identified as PS, Ge/PS and ZnO/Ge/PS samples, respectively. Pd finger contacts were deposited on the PS and embedding PS (Ge/PS and ZnO/Ge/PS) to form Pd on PS hydrogen sensors using RF magnetron sputtering. SEM and EDX suggested the presence of substantial Ge and ZnO inside the uniform circular pores for Ge/PS and ZnO/Ge/PS samples, respectively. Raman spectra showed that good crystalline Ge and ZnO nanostructures embedded inside the pores were obtained. For hydrogen sensing, Pd on ZnO/Ge/PS Schottky diode exhibited a dramatic change of current after exposure to H2 as compared to PS and Ge/PS devices. It is observed that the sensitivity increased exponentially with the hydrogen flow rate for all the sensors. The ZnO/Ge/PS showed more sensitivity towards H2 than that of PS and Ge/PS especially at high flow rate of H2 with higher current gain (69.11) and shorter response (180 s) and recovery times (30 s). Penerbit Universiti Kebangsaan Malaysia 2022 Article PeerReviewed application/pdf en http://journalarticle.ukm.my/21209/1/SDB%2017.pdf Alhan Farhanah Abd Rahim, and Nurul Syuhadah Mohd Razali, and Rosfariza Radzali, and Ainokhilah Mahmood, and Irni Hamiza Hamzah, and Mohamed Fauzi Packeer Mohamed, (2022) Enhanced catalytic palladium embedded inside porous silicon for improved hydrogen gas sensing. Sains Malaysiana, 51 (12). pp. 4087-4098. ISSN 0126-6039 http://www.ukm.my/jsm/index.html
spellingShingle Alhan Farhanah Abd Rahim,
Nurul Syuhadah Mohd Razali,
Rosfariza Radzali,
Ainokhilah Mahmood,
Irni Hamiza Hamzah,
Mohamed Fauzi Packeer Mohamed,
Enhanced catalytic palladium embedded inside porous silicon for improved hydrogen gas sensing
title Enhanced catalytic palladium embedded inside porous silicon for improved hydrogen gas sensing
title_full Enhanced catalytic palladium embedded inside porous silicon for improved hydrogen gas sensing
title_fullStr Enhanced catalytic palladium embedded inside porous silicon for improved hydrogen gas sensing
title_full_unstemmed Enhanced catalytic palladium embedded inside porous silicon for improved hydrogen gas sensing
title_short Enhanced catalytic palladium embedded inside porous silicon for improved hydrogen gas sensing
title_sort enhanced catalytic palladium embedded inside porous silicon for improved hydrogen gas sensing
url http://journalarticle.ukm.my/21209/
http://journalarticle.ukm.my/21209/
http://journalarticle.ukm.my/21209/1/SDB%2017.pdf