Hydrothermally synthesized graphene-titanium (IV) oxide nanocomposite for sensing applications

• Main Authors: Albelda, Jasmine Angelie V., Uzunoglu, Aytekin, Santos, Gil Nonato C., Stanciu, Lia A.
• Format: text
• Published: Animo Repository 2016
• Subjects: Titanium dioxide; Nanocomposites (Materials); Physics
• Online Access: https://animorepository.dlsu.edu.ph/faculty_research/12072
• Institution: De La Salle University

We report on a facile hydrothermal preparation of graphene-titanium (IV) oxide (Gr-TiO2) nanocomposite. The effect of various synthesis conditions such as autoclaving time and mass-volume loading of graphene and titanium isopropoxide (TTIP) nanoparticle precursor were investigated. The nanocomposites were characterized by TEM, XRD, FTIR, TGA, and BET. Furthermore, the nanocomposites were assessed for their electron transfer rates using the redox couples [Fe(CN)6]−3/−4 and [Ru(NH3)6]+3/+2 respectively. Then, the electrochemical behavior of hypoxanthine at the Gr-TiO2 modified glassy carbon electrode was investigated. Results showed that TiO2 nanoparticles were uniformly dispersed on the surface of graphene. The nanocomposite synthesized at 130 0C for 12 hours using 1:5 mass/volume ratio of graphene and TTIP yields the highest BET surface area if 136.4 m2/g and fastest apparent heterogeneous electron transfer rate, k value of 0.0090 cm s-1 for [Fe(CN)6]−3/−4 and k value of 0.0360 cm s-1 [Ru(NH3)6]+3/+2. The Gr/TiO2 nanocomposite offered a favorable microenvironment for direct electrochemistry of xanthine oxidase (XOD) and exhibited excellent electro catalytic activity towards hypoxanthine. It is a promising material to be used as biosensing platform in the construction of electrochemical sensors.