Malaysian Journal of Analytical Sciences Vol 23 No 1 (2019): 90 - 99

DOI: 10.17576/mjas-2019-2301-11






(Salutan nanopartikel TiO2 ke atas Substrat Kaca Melalui Teknik Mudah untuk Penyingkiran Bahan Pencemar Udara dalaman Melalui Proses Fotokatalisis)


Kah Hon Leong1*, Jia Quan Lee2, A. Ashok Kumar3, Lan Ching Sim1, Saravanan Pichiah4


1Department of Environmental Engineering, Faculty of Engineering and Green Technology,

Universiti Tunku Abdul Rahman, Jalan Universiti, Bandar Barat, 31900 Kampar, Perak, Malaysia

2Environmental Engineering Laboratory, Department of Civil Engineering, Faculty of Engineering,

University of Malaya, 50603 Kuala Lumpur, Malaysia

3Department of Chemical Engineering, School of Engineering and Technology,

Periyar Maniammai University, Thanjavur - 613 403, India

4Department of Environmental Science and Engineering,

Indian Institute of Technology (ISM) Dhanbad- 826004, Jharkhand, India


*Corresponding author:



Received: 13 April 2017; Accepted: 17 April 2018




Self-cleaning technology employing titania (TiO2) photocatalysts has major applications in the removal of indoor air pollutants. Pollutant removal efficiency significantly depends on the properties of the photocatalyst thin film, which is deposited on substrates. The present work developed a facile immobilisation technique that is based on simple sol–gel process. In this technique, TiO2 nanoparticles are spray-coated onto a porous glass substrate. The uniformity of the TiO2 coating on the glass surface was studied using a dynamic flowsense charge-coupled device camera. The influence of different TiO2 nanoparticle concentrations in the ethanol phase was identified through rheological analysis, which showed that nanoparticle concentration is a crucial factor that affects the uniformity of the coating layer. The ability of the obtained material to catalyse formaldehyde photodegradation in presence of artificial UV light was investigated. Results demonstrated that >15.0 g/L TiO2 is required to activate formaldehyde photodegradation and that uniform surface coatings with sufficient surface thickness can be obtained by spraying TiO2 nanoparticles on glass substrates at concentrations of more than 15.0 g/L. This study demonstrated that uniformly coated photocatalysts for the efficient self-cleaning of indoor air pollutants can be fabricated through a facile technique.


Keywords:  self-cleaning, TiO2, sol-gel, formaldehyde, photocatalysis



Teknologi pembersihan menggunakan TiO2 sebagai fotokatalis yang memainkan peranan penting terutamanya dalam menyingkirkan bahan pencemar udara dalaman. Pembersihan bahan pencemar ini sangat bergantung kepada ketebalan filem salutan terbentuk pada substrat. Dalam kajian ini teknik mudah dapat dicapai melalui proses sol-gel dan diikuti dengan salutan semburan TiO2 berliang nanopartikel ke atas substrat kaca. Keseragaman pembentukan titania bersalut pada permukaan kaca dikaji menggunakan kamera “gabungan cas dinamik flowsense. Pengaruh kepekatan nanopartikle TiO2 yang berbeza-beza dalam fasa etanol membawa kepada analisis reologi. Kajian reologi menunjukkan keberkesanan kepekatan nanopartikel bagi mendapatkan lapisan salutan yang seragam. Keberkesanan salutan dinilai dengan penyingkiran formaldehid dalam kehadiran cahaya UV tiruan. Keputusan penyingkiran menunjukkan bahawa kepekatan TiO2 yang tinggi dengan melebihi 15.0 g/L menunjukkan penyingkiran formaldehid pada tahap yang ketara disebabkan oleh keseragaman salutan pada permukaan kaca serta ketebalan permukaan yang mencukupi. Kajian ini menunjukkan prestasi yang baik dalam mengesahkan salutan fotokatalis yang seragam untuk meningkat keberkesanan penyingkiran bahan pencemar udara dalaman.


Kata kunci:  penyingkiran, TiO2, sol-gel, formaldehid, fotokatalisis



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