Jurnal Kimia Valensi, Vol 6(2), November 2020, 208-214 Available online at Website: http://journal.uinjkt.ac.id/index.php/valensi Deconvolution of TEOS/TEVS Xerogel by Single or Dual Organic Catalyst Addition Anna Sumardi 1,2 , Muthia Elma 1,2* , Aptar Eka Lestari 1,2 , Zaini Lambri Assyaifi 1,2 , Adi Darmawan 3 , Isna Syauqiah 1 , Erdina Lulu Atika Rampun 1,2 , Yanti Mawaddah 1,2 , Linda Suci Wati 1,2 1 Chemical Engineering Department,Universitas Lambung Mangkurat (ULM) Jl. A. Yani KM 36, Banjarbaru, Kalimantan Selatan 70714,Indonesia 2 Materials and membranes Research Group (M2ReG), Universitas Lambung Mangkurat Jl. A.Yani KM 36, Banjarbaru, Kalimantan Selatan 70714, Indonesia 3 Chemical Engineering Department, Universitas Diponegoro, Semarang 50275, Indonesia *Corresponding author: melma@ulm.ac.id Received: October 2020; Revision: October 2020; Accepted: February 2021; Available online: February 2021 Abstract Currently, xerogel has been applied as a filtration material, especially in membrane desalination. However, the xerogel matrix structure for desalination have to be designed properly in order to allow rejection of salt and obtain good hydro-stability, thus, silica precursor in the form of TEOS (tetraethyl orthosilicate)/TEVS (triethoxy vinyl silane) and organic acid catalyst are suitable material for fabrication. The aim of this study is therefore to fabricate and perform deconvolution of TEOS/TEVS xerogel by adding single or dual catalyst, using FTIR (Fourier-transform Infrared Spectroscopy) and Fityk software. The xerogel was fabricated by dried silica sol and calcined using RTP technique (rapid thermal processing) at 450 °C. Prior to this fabrication, the silica sol was synthesized by sol gel method, using a mixture of silica precursor TEOS/TEVS, ethanol solvent, and varied addition of single catalyst (citric acid) as well as dual catalyst (citric acid + ammonia) for 2 hours, at 50 °C. Subsequently, the xerogel was characterized by FTIR and the deconvolution was obtained through Gaussian approach, with Fityk software. All TEOS/TEVS xerogel samples indicated existence of silanol (Si-OH), siloxane (Si-O-Si) and silica-carbon (Si-C) functional groups. The xerogel deconvolution of TEOS/TEVS using single catalyst exhibit a peak area ratio of Si-OH/Si-O-Si, and this is similar to the dual catalyst counterpart of 0.24 (unit area) and 1.86 (unit area), for Si-C area ratio. This shows the addition of single catalyst was enough to produce deconvolution in TEOS/TEVS xerogel, dominated by siloxane functional group and carbon bonds with the ability to enhance membrane material hydro-stability’s fabrication. Keyword: Single catalyst, dual catalyst, TEOS/TEVS, xerogel, and membrane desalination. DOI: https://doi.org/10.15408/jkv.v6i2.17597 1. INTRODUCTION Xerogel is a hydrogel with water content removable through a conventional process involving pressure or temperature increase (Ayu et al., 2013; Czarnobaj, 2008). This hydrogel has been widely used as a catalyst, adsorbent, filtration and for other purposes. Generally, silica based xerogels are preferred for membrane filtration applications, due to the numerous advantages as a desalination membrane, including good strength, resistance to high temperatures, as well as high selectivity especially for separating salt and water molecules. Silica xerogel material are obtained from various precursors, including 1,2-bis (triethoxysilyl) ethane (BTESE) (Gao et al., 2017), tetramethylammonium hydroxide (TMAH) (Sakai et al., 2018), TEOS (tetraethyl orthosilicate) (Lestari R. A. et al., 2020; Wiyono, 2015) and TEVS (triethoxy vinyl silane) (Elma et al., 2015a). However, the silica material in desalination membrane is limited by low hydro-stability due to the presence of hydrophilic silanol (Si-OH) groups (Elma et al., 2020c; Elma et al., 2020e; Maimunawaro et al., 2020; Rahma et al., 2020a). The silanol group is reduced by inserting metal or carbon materials into the silica matrices (Pratiwi et al., 2019). Previous studies