Vol.8 (2018) No. 5 ISSN: 2088-5334 Visible Light Absorption and Photo-Sensitizing Characteristics of Natural Dye Extracted from Mangosteen Pericarps Using Different Solvents Nofrijon Sofyan #♣ , Aga Ridhova # , Kalisha R.O. Pramono # , Akhmad H. Yuwono #♣ , Arief Udhiarto * # Department of Metallurgical and Materials Engineering, Faculty of Engineering, Universitas Indonesia, Depok 16424 Indonesia E-mail: nofrijon.sofyan@ui.ac.id, aga.ridhova@ui.ac.id, khalisha.rizqi@ui.ac.id, ahyuwono@eng.ui.ac.id ♣ Tropical Renewable Energy Centre, Faculty of Engineering, Universitas Indonesia, Depok 16424 Indonesia * Department of Electrical Engineering, Faculty of Engineering, Universitas Indonesia, Depok 16424 Indonesia E-mail: aried.udhiarto@ui.ac.id Abstract—Dye is an important factor in determining the efficiency of a dye-sensitized solar cell (DSSC) device. One of the dyes derived from natural resource is anthocyanin. At the same time, one of the natural resources containing anthocyanin is a tropical plant called mangosteen. In this work, the characteristics of anthocyanin extracted from mangosteen pericarps using different solvents have been examined. The anthocyanin was extracted from mangosteen pericarps using various different solvents, i.e. dry ethanol, ethanol containing 1% HCl, and ethanol containing 1% acetic acid. Absorption characteristic of dye extracted from different solvents was determined using ultraviolet-visible spectroscopy (UV-Vis). Fourier transform infrared (FTIR) was used to examine the functional groups of the extracted dye. Visible light absorption and photo-sensitizing characteristics of the extracted natural dye were then investigated through their applications in a DSSC device. The results from infrared characterization showed that all of the extracted dyes indicated the same tendency with the characteristic of anthocyanin. At the same time, the UV-Vis examination revealed that the dye extracted using solvent HCl 1% acidified ethanol was found to have a visible light absorption at a wavelength of 533 nm. This result indicated that HCl 1% acidified ethanol was the best solvent to extract anthocyanin from mangosteen pericarps. The activity of the DSSC device sensitized using the extracted dye through a photocurrent-voltage examination showed a power conversion efficiency of 0.23% and 0.18% for the device using the commercial dye and the mangosteen extracted dye, respectively. This result is quite convincing and promising for the next DSSC device development using natural dye extracted from mangosteen pericarps. Keywords— anthocyanin; dye-sensitized solar cell; mangosteen; natural dyes; power conversion efficiency. I. INTRODUCTION Dye sensitized solar cells (DSSCs) are photo- electrochemical devices that mimics the effects of photosynthesis using a simple electrochemical principle, i.e. by capturing photon energy at the molecular level and directly convert it into electrical energy [1]. DSSCs have taken much attention especially because of their low cost in manufacturing process, ease of fabrication, flexibility, and at the same time maintains its relatively high-power conversion efficiency [2]. In general, a DSSC device consists of an electrode made of thin layer of porous semiconductor coated transparent conducting glass and a dye that serves as light sensitizer, an electrolyte layer, and a counter electrode made of graphite or platinum coated conducting glass [3], [4]. In a DSSC device, dye-sensitizer serves as a solar absorber and transforms it into electrical energy. Because of that, it is considered as an important portion of a DSSC device. Moreover, since the dye and its functional groups will help promoting electron injection into the semiconductor band, it surely will increase the efficiency of a DSSC device. Thus, the absorption spectrum of a dye would be an important factor in selecting a dye in order to increase a DSSC conversion efficiency [2], [3]. These dye molecules are what make DSSCs unique among other types of solar cells. There have been many studies and researches to explore the dye molecules from alternative green sources such as from extracted plant parts, e.g. roots, bark, leaves, flowers, fruits, vegetables, and flowers called natural dye-sensitized 2059