Graphene oxide and Ag engulfed TiO₂ nanotube arrays for enhanced electron mobility and visible-light-driven photocatalytic performance

Abstract

were investigated using the composite of Ag nanoparticles (Ag NPs) and graphene oxide (GO) deposited over TiO 2 nanotube arrays (TNTs). The resulting TNTs in the composite showed 100% anatase phase with no occurrence of the rutile phase. An implicit microscopic and spectroscopic technique (FESEM, HRTEM, FTIR and Raman analysis) confirmed the presence of Ag NPs and GO in the composite photocatalyst. It also exhibited an evident shift of the absorption edge in the visible range. The successful depositions of Ag contributed to improved photocatalytic activity in the visible spectrum owing to the existence of localized surface plasmon resonance (LSPR), and further the deposition of GO minimized the recombination of electron-hole pairs. The photocatalytic degradation of both MB and 2-CP followed pseudo-second order kinetics. In the primary run, both MB and 2-CP exhibited almost similar degradation efficiency of 68.3 and 66.8%, respectively. The reusability studies showed a deprived performance for MB degradation than that of 2-CP, due to chemisorption of MB. The prepared composite exhibited significantly larger enhancement in the photocatalytic oxidation of pollutants with greater electrons mobility to reactive sites of GO and Ag. 03 7967 5318; Tel: +60 03 7967 7678 † Electronic supplementary information (ESI) available: FTIR spectra of GO-Ag-TNTs before and aer the adsorption of MB, photocatalytic degradation kinetic parameters and kinetic plots of rst order and second order. SeeFig. 7 (a) Photoluminescence spectra of TNTs, Ag-TNTs and GO-Ag-TNTs. Core level XPS spectra of (b) Ti 2p (c) Ag 3d and (d) C 1s of GO-Ag-TNTs.This journal is

Fabrication and Photocatalytic Properties of TiO2/Reduced Graphene Oxide/Ag Nanocomposites with UV/Vis Response

“…High emission intensity corresponds to a faster recombination rate, and low emission intensity implies that more photogenerated electrons can be transferred. [53] As shown in Figure 7 (b), the emission intensity of TiO 2 displays a clear decrease after modification by rGO and the Ag nanoparticles, which suggests that both rGO and Ag can effectivity improve the transformation rate of the electrons to suppress recombination of electron-hole pairs. [38] Figure 7.…”

Photocatalytic Degradation and Hydrogen Production of TiO2/Carbon Fiber Composite Using Bast as a Carbon Fiber Source

“…In the hydrogen ambience with 100 sccm, the fiber was heated to 300°C at a rate of 10°C/min and then maintained for 1.5 h. The biomass 2 International Journal of Photoenergy carbon fiber was obtained after cooling down. Different amounts of TiO 2 nanoparticles (P25) were dispersed into 50 mL deionized water with strong ultrasonic to attain homogenous dispersion (5,10,15, and 20 g/L, resp.). After immersing the biomass carbon fiber into TiO 2 dispersion for several minutes, the composites were annealed at 450°C under H 2 ambience.…”

“…The application of TiO 2 nanomaterials is greatly limited due to the poor visible light response and high charge recombination rate, originating from the wide band gap (3.2 eV for anatase and 3.0 eV for rutile) and the relatively high electrical resistance. TiO 2 is combined with carbon species such as carbon nanotubes, graphene, carbon fiber, and graphite-like carbon to form TiO 2 /carbon composites [8][9][10][11][12] due to the good adsorbability and strong charge transport ability [13,14].…”

Silver nanoparticles decorated anatase TiO 2 nanotubes for removal of pentachlorophenol from water

“…Noble metals, such as gold (Au) and silver (Ag), can absorb visible light due to the existence of localized surface plasmon resonance (LSPR) [30]. Moreover, these metals can act as electron traps in the metal-TiO 2 nanostructures and function as electron donors to promote electron transfer from metal to TiO 2 , thus minimizing the recombination of photo-generated electron-hole pairs in the surface of TiO 2 [30,31].…”

“…Moreover, these metals can act as electron traps in the metal-TiO 2 nanostructures and function as electron donors to promote electron transfer from metal to TiO 2 , thus minimizing the recombination of photo-generated electron-hole pairs in the surface of TiO 2 [30,31]. Wang et al synthesized mesoporous Au/TiO 2 microspheres [32], Au nanoparticles act as sensitizers which effectively promoted the separation of visible-light photo-generated electron-hole pairs because of their strong LSPR.…”