SINTESIS NANOPARTIKEL Fe3O4/SiO2/TiO2 TERSENSITISASI POLIANILINA SEBAGAI FOTOKATALIS UNTUK FOTOREDUKSI ION Au(III) DALAM LARUTAN [AuCl4]-; SYNTHESIS OF POLYANILINE SENSITISIZED Fe3O4/SiO2/TiO2 NANOPARTICLE AS A PHOTOCATALYST FOR PHOTOREDUCTION OF Au(III) ION IN [AuCl4]- SOLUTION

Budi, Iis Setyo, Eko Sri Kunarti

2016 | Skripsi | FMIPA

Synthesis of polyaniline sensitized Fe3O4/SiO2/TiO2 nanoparticle and its application as catalyst for photoreduction of Au(III) ion from [AuCl4]- solution have been investigated. The synthesis started with the preparation of magnetite (Fe3O4) through coprecipitation and sonication system, followed by coating SiO2 on the magnetite via hydrolysis reaction, coating TiO2 using sol-gel process and polimerization of aniline using ammonium peroxydisulfate as polimerization initiator. The products were characterized using X-ray diffractometer, infrared spectrophotometer, scanning electron microscope-energy dispersive X-ray, transmission electron microscope, vibrating sample magnetometer, and diffuse reflectance spectrophotometer. Photoreactivity test of the polyaniline sensitized Fe3O4/SiO2/TiO2 magnetic photocatalyst was conducted by mixing the photocatalyst and [AuCl4]- solution in a batch system at pH 5 for 180 minutes without and with irradiation of ultraviolet and visible lights. Results indicate that polyaniline sensitized Fe3O4/SiO2/TiO2 nanoparticle has a good magnetic characteristic with lower magnetic capability than Fe3O4/SiO2/TiO2 and Fe3O4. The polyaniline sensitized Fe3O4/SiO2/TiO2 nanoparticle photocatalyst was responsive toward UV and visible lights with the absorption peaks of diffuse reflectance UV-visible spectra on 397 nm and 670 nm. The photocatalyst has the ability to photoreduce Au(III) ion better than that of Fe3O4/SiO2/TiO2 and TiO2, with the photoreduction yield was 89% and 92% under UV and visible light, respectively.

Kata Kunci : TiO2, Au(III) ion, Fe3O4, sensitisized polyaniline.