The main objectives of this study is to investigate the properties of photoactive Nano TiO2 thin film-geopolymer based on laterite soils deposit Gowa regency as self-cleaning material. The soil was clean, grounded, sieves 200 mesh and dehydroxylated at 750 for 2 hours. Nano TiO2 was prepared through ball milling process for 10 hours. The geopolymers was synthesized through alkali activation method by adjusting the molar oxide ratios of SiO2/(Al2O3+Fe2O3), Na2O/SiO2 and H2O/Na2O in accordance with the chemical compositions of the soils. Nano TiO2 was added into geopolymers paste at different concentration namely 0.5% and 1.0% (relative to the mass of laterite soils) by using spray method. The self-cleaning properties of the sample were observed by immersing the sample into clays solution then irradiated under UV lamp for 24 hours. The X-Ray Diffraction (XRD) was performed to examine the structure and phase of the sample. The surface morphology of geopolymers was studied by using scanning electron microscopy (SEM). The measurements results showed that photoactive Nano TiO2-geopolymers composite can be applied as self-cleaning materials.

This study utilized fly-ash and TiO2/rGO as raw materials to produce membrane for absorbing harmful heavy metals and liquid organic waste. Graphene oxide (GO) was synthesized by using modified Hummer’s method and then transformed into reduced Graphene Oxide (rGO) by means of hydrothermal reduction at 160°C for 4 hours. The objective of this research was to identified the structure and morphology as well as the ability of the produced membrane to absorb heavy metals. The x-ray diffraction (XRD) examination showed the high purity of GO and rGO nanoparticles. Scanning electron microscopy (SEM) images for each TiO2 concentration showed that membrane added with 1% TiO2 result in homogenous distribution of TiO2 and rGO on the surface of geopolymer. Atomic Absorption Spectroscopy (ASS) showing significant differences of Fe heavy metal of the contaminant concentration before and after filtration. Fe concentration in the first concentration was 1.226 ppm and become 0.239 ppm after filtration process was performed. The results of this study indicate that the membrane based on geopolymer/TiO2-rGO contain 1% of TiO2 and rGO relative to the mass of the starting fly-ash can be used as a membrane of heavy metal absorption.

RGO and P-RGO samples based on coconut shell waste have been synthesized by exfoliation method. These samples were characterized using XRD, FTIR, and UV-Visible spectroscopy to obtain their crystal structure, functional group and optical properties. XRD results of the RGO and P-RGO samples show two peaks that are similar to those of RGO and P-RGO synthesized from pure (commercial) graphite. FTIR characterization of the RGO sample shows the hydroxyl (-OH), aromatic (-CC), epoxy (C-O) and alkoxy (C-O) functional groups at 3449.39, 1627.63, 1216.58 and 1045.88 cm -1 , respectively. Meanwhile, the P-RGO sample shows the hydroxyl (-OH), aromatic (C  C) and epoxy (CO) functional groups formed at 3450.51, 1628.02 and 1229.14 cm -1 , respectively. In addition, UV-Visible results for RGO and P-RGO show sufficient optical performance. The band gap energy values of the samples obtained using the Tauc plot method are 3.50 eV and 4.41 eV, indicating the semiconductor properties.