Plasmon Induced Nano Au Particle Decorated over S,N-Modified TiO₂ for Exceptional Photocatalytic Hydrogen Evolution under Visible Light

Abstract

Nano Au deposited mesoporous S,N-TiO2 (SNT) nanocomposites have been fabricated through deposition precipitation technique by employing urea as the hydrolyzing agent. To investigate the structural, optical, and electronic properties, the photocatalysts are characterized through X-ray diffraction (XRD), UV-vis diffuse reflectance spectra, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and photoelectrochemical measurements. Here in addition to the co-catalyst nature of nano Au particles, surface plasmon resonance (SPR) effect in visible region enhances the light harvestation ability as well as transfer electrons to the conduction band of SNT. Furthermore, easy channelization of photogenerated charge carriers through sulfate facilitated redox couple makes the system more potential towards H2 evolution. TEM study exhibits well interconnective morphology in the matrix which helps easy channelization of electrons in the SNT nanocomposites. The photocatalytic activities have been evaluated for hydrogen generation under the irradiation of visible light and an enhanced activity has been observed for the Au promoted SNT due to the presence of nano Au particles, that is, 3.5 nm. The hydrogen generation activity of 3Au-SNT is nearly 9 times higher than that of neat SNT, and the energy conversion efficiency was found to be 17.6 %.

Cr(VI) remediation from aqueous environment through modified-TiO2-mediated photocatalytic reduction

“…(ii) The recombination of excited charge carriers in bare TiO 2 takes place at such a high rate that more than 90% of the recombination processes occur in 10 ns [79], leaving behind a small fraction of the excited carriers to be transferred to the surface of TiO 2 . This low electron transfer rate on the interface and fast recombination of photoinduced charge carriers causes its poor photocatalytic and photoelectrochemical efficiency [80–83]. (iii) The tendency of nanostructured TiO 2 to agglomerate results in difficulties during the separation process [84].…”

Water splitting catalyzed by titanium dioxide decorated with plasmonic nanoparticles

“…The Al 2 O 3 layer between Au@TiO 2 and Cu 2 O increases the interfacial charge separation and the sensitivity of the device. Other methods such as nitrogen doping [59] have been used to lower the band gap of TiO 2 by creating localized state lower in energy and thus promote charge carrier separation [60].…”

A facile in situ approach to fabricate N,S-TiO2/g-C3N4 nanocomposite with excellent activity for visible light induced water splitting for hydrogen evolution

“…1,2 Unfortunately, two of its major drawbacks hinder its potential applications: one is its large band gap energy (i.e. [10][11][12][13][14][15][16] Recently, promising results have been achieved through the coupling of wide band gap semiconductors with narrow gap ones. Therefore, researchers are striving towards the development of titania based visible light active photocatalysts.…”