Graphitic carbon nitride (g-C₃N₄) coated titanium oxide nanotube arrays with enhanced photo-electrochemical performance

Abstract

Herein, we report the successful formation of graphitic carbon nitride coated titanium oxide nanotube array thin films (g-C3N4/TiO2) via the facile thermal treatment of anodized Ti sheets over melamine. The proportion of C3N4 and TiO2 in the composite can be adjusted by changing the initial addition mass of melamine. The as-prepared samples are characterized by several techniques in order to understand the morphological, structural, compositional and optical properties. UV-vis absorption studies exhibit a remarkable red shift for the g-C3N4/TiO2 thin films as compared to the pristine TiO2 nanotubes. Importantly, the prepared composites exhibit an enhanced photocurrent and photo-potential under both UV-vis and visible light irradiation. Moreover, the observed maximum photo-conversion efficiency of the prepared composites is 1.59 times higher than that of the pristine TiO2 nanotubes. The optical and electrochemical impedance spectra analysis reveals that the better photo-electrochemical performance of the g-C3N4/TiO2 nanotubes is mainly due to the wider light absorption and reduced impedance compared to the bare TiO2 nanotube electrode. The presented work demonstrates a facile and simple method to fabricate g-C3N4/TiO2 nanotubes and clearly revealed that the introduction of g-C3N4 is a new and innovative approach to improve the photocurrent and photo-potential efficiencies of TiO2.

Enhanced Visible Light Photocatalytic Reduction of Cr(VI) over a Novel Square Nanotube Poly(Triazine Imide)/TiO2 Heterojunction

“…The holes stored in the VB of PTI could oxidize water to form O 2 , further promoting the photocatalytic performances of PTI/TiO 2 heterojunction. This is in good agreement with the literature [34][35][36][37].…”

Synthesis of α-Bi2Mo3O12/TiO2 Nanotube Arrays for Photoelectrochemical COD Detection Application

“…For further investigation, electrochemical impedance spectroscopy (EIS) is an effective method for studying the charge transfer process in the photoelectrochemical process. , Figure b exhibits EIS plots of different electrodes in the frequency range from 10 –1 to 10 5 at a potential of 0.1 V. The Nyquist plot of the α-Bi 2 Mo 3 O 12 /TiO 2 NTAs electrode has a semicircle similar to that of TiO 2 NTAs in the dark, indicating that α-Bi 2 Mo 3 O 12 modification cannot enhance the electrical conductivity of TiO 2 nanotubes. However, the semicircle of α-Bi 2 Mo 3 O 12 /TiO 2 NTAs under illumination is much small than that of TiO 2 NTAs, implying the fast transfer of photogenerated charge carriers under illumination.…”

“…38,39 The PL spectra of TiO 2 and α-Bi For further investigation, electrochemical impedance spectroscopy (EIS) is an effective method for studying the charge transfer process in the photoelectrochemical process. 40,41 Figure 9b The efficient charge separation and fast charge transfer increase the lifetime of the charge carriers and enhance the photoelectrochemical efficiency, which are the basis for the photoelectrochemical determination. 42 However, they still cannot explain the low background photocurrents in buffer solution and high current response with the addition of organics.…”

Visible Light-Driven Photocatalytic Performance of N-Doped ZnO/g-C3N4 Nanocomposites

“…Graphitic carbon nitride (g-C 3 N 4 ) is a relatively novel, versatile, and promising metal-free polymeric semiconductor photocatalyst [ 12 – 14 ], due to its special semiconducting properties and low cost. It has been widely investigated for its great potential in degrading environmental pollutants [ 12 ], catalyzing water splitting for H 2 evolution [ 13 ], and reducing carbon dioxide [ 14 ] under irradiation. However, the easy recombination of its photogenerated charges restricts its photocatalytic performance and greatly limits its wide practical application [ 15 ].…”