Tujuan utama penyelidikan ini adalah untuk mengkaji prestasi pengesanan sensor gas tin dioksida (SnO2) berliang- meso yang dibina melalui kaedah salutan jatuhan terhadap wap etanol. Penyelidikan ini dimulakan dengan sintesis serbuk SnO2 berliang meso yang dijalankan melalui proses hidrolisis tin (IV) klorida dengan surfaktan kationik, bromida cetyltrimethylammonium (CTAB) dan ammonia, diikuti dengan proses pengkalsinan. Serbuk SnO2 berliang-meso telah dicirikan dengan mengunakan Mikroskop Elekton Mengimbas (SEM), Pembelau X-ray (XRD) dan Penganalisa Luas Permuakaan BET. Serbuk SnO2 berliang-meso yang mempunyai luas permukaan yang tinggi iaitu 164.99 m2/g telah diperolehi. Seterusnya, serbuk SnO2 berliang-meso yang disentesis dan serbuk SnO2 komersial telah disalutkan di atas substrat alumina menggunakan kaedah salutan jatuhan dan telah digunakan untuk mengkaji tindakbalas terhadap kepekatan wap etanol yang berbeza (100 – 1000 ppm) dalam suhu yang berbeza (150 – 400 °C). Hasil kajian mendapati bahawa suhu operasi yang optimum bagi sensor gas SnO2 berliang-meso adalah lebih rendah berbanding dengan sensor gas komersial SnO2, iaitu pada 300 °C. Selain itu, didapati bahawa kepekaan sensor gas yang dibangunkan berkadar terus dengan kepekatan wap etanol. Tambahan pula, prestasi sensor gas SnO2 berliang-meso telah dibandingkan dengan sensor gas SnO2 komersial. Keputusan eksperimen menunjukkan bahawa sensor gas SnO2 berliang-meso mempunyai kepekaan yang lebih tinggi dalam pengesanan wap etanol. Penemuan ini telah dianalisa dengan menghubungkaitkan dengan ciri-ciri SnO2.
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The primary purpose of this project is to study the ethanol vapour sensing performance of tin dioxide (SnO2) gas sensor fabricated through drop-coating method. Mesoporous SnO2 powders were synthesized via a simple SnCl4 hydrolysis process using cationic surfactant, cetyltrimethylammonium bromide (CTAB and ammonia, combined with a subsequent calcinations process. The synthesized mesoporous SnO2 powders were characterized by Scanning Electron Microscope (SEM), XRD Diffractometer (XRD) and BET surface area analyser. Mesoporous SnO2 powders high surface area of 164.99 m2/g were obtained. Then, the synthesized mesoporous SnO2 and commercial SnO2 powders were coated on alumina substrates through drop-coating method. The fabricated gas sensors were used to test their responses to different concentrations of ethanol gas (100 – 1000 ppm) at different operating temperatures (150 – 400 °C). The results show that the optimum operating temperature for the mesoporous SnO2 gas sensor was lower than commercial SnO2 gas sensor that was at 300 °C. Besides that, it was found that the sensitivity of the sensor varied proportionally with the concentration of ethanol gas. Furthermore, the performance of the mesoporous SnO2 sensor was compared with the commercial SnO2 sensor. The results showed that the mesoporous SnO2 sensor has higher sensitivity in detecting ethanol vapour. The findings were analyzed and discussed by correlating the experimental results with the characterization analysis which were closely related to the properties of the sensing materials.
Ethanol sensing performance of mesoporous sno2-based thick film gas sensors / Kam Li Ming