Synthesis of TiO2 nanosheets/graphene quantum dots and its application for detection of hydrogen peroxide by photoluminescence spectroscopy

Abstract

TiO2 nanosheets/graphene quantum dots (TiO2 NSs/GQDs) have been successfully developed using a simple and rapid process at 60 °C for 30 min. The GQDs were obtained using a natural source of rice starch and ascorbic acid, a reducing agent, under a rapid and simple microwave-assisted synthetic method for 10 min; and TiO2 NSs were synthesized by hydrothermal method. The synthesized TiO2 NSs/GQDs were characterized by Ultraviolet-visible spectroscopy (UV-vis), Fourier-transform infrared spectroscopy (FTIR), X – ray Diffractometry (XRD), Transmission Electron Microscopy (TEM), and Energy Dispersive X-Ray Analysis (EDX). The novel TiO2 NSs/GQDs were successfully synthesized, possessed an average particle size of ∼10–15 nm (TiO2 NSs) and ∼8–10 nm (GQDs), and were homogenously distributed in the dispersion. Regarding the catalytic application, the TiO2 NSs/GQDs demonstrated high catalytic and photocatalytic activity for the detection of hydrogen peroxide (H2O2) by photoluminescence spectroscopy at an excitation wavelength of 360 nm, with a low H2O2 limit of detection (LOD) of 10−14 M and a wide detection range from 10−14 M to 10−2 M.