Molybdenum impregnated g-C3N4 nanotubes as potentially active photocatalyst for renewable energy applications

Abstract

Molybdenum (Mo) impregnated g-C3N4 (Mo-CN) nanotubes are fabricated via a thermal/hydrothermal process to augment photoelectrochemical properties during solar-driven water-splitting (SDWS) reactions. Graphitic-C3N4 is an attractive material for photocatalysis because of its suitable band energy, high thermal and chemical stability. The FE-SEM and HR-TEM comprehend the nanotube-like morphology of Mo-CN. The spectroscopic characterization revealed bandgap energy of 2.63 eV with high visible-light activity. The x-ray diffraction of pristine g-C3N4 and Mo-CN nanotubes discloses the formation of triazine-based nanocrystalline g-C3N4, which remains stable during hydrothermal impregnation of Mo. Furthermore, Mo-CN nanotubes possess high sp2-hybridized nitrogen content, and metallic/oxidized Mo nanoparticles (in a ratio of 1:2) are impregnated into g-C3N4. The XPS analysis confirms C, N, and Mo for known atomic and oxidation states in Mo-CN. Furthermore, high photocurrent efficiency (~ 5.5 mA/cm2) is observed from 5%-Mo-CN nanotubes. That displays efficient SDWS by 5%-Mo-CN nanotubes than other counterparts. Impedance spectroscopy illustrated the lowest charge transfer resistance (Rct) of 5%-Mo-CN nanotubes, which further confirms the fast electron transfer kinetics and efficient charge separation resulting in high photocurrent generation. Hence, 5%Mo-CN composite nanotubes can serve as a potential photocatalytic material for viable solar-driven water splitting.

Highly Effective Electrochemical Water Oxidation by Millerite-Phased Nickel Sulfide Nanoflakes Fabricated on Ni Foam by Aerosol-Assisted Chemical Vapor Deposition

“…Because of their low overpotential, good stability, and effective overall water splitting, noble metal-based catalysts have long been recognized as competent electrochemical water-splitting materials. − However, on large-scale production commercially, their feasibility turns out to be low because of high cost and scarce availability. Thus, it remains a great challenge to develop an inexpensive, highly stable, efficient, and robust catalyst for electrochemical water splitting. , Transition-metal catalysts are known as earth-abundant and eco-friendly materials for their electrocatalytic activity.…”

Light Promotes the Immobilization of U(VI) by Ferrihydrite

“…From Figure 1 C, ferrihydrite exhibited an obvious absorbance for visible light. The corresponding bandgap (Eg) of ferrihydrite was estimated to be 1.70 eV using the Tauc plots transferred from Kubelka–Munk function (inset in Figure 1 C) [ 37 ]. The VB-XPS was collected to evaluate the valance band potential (E VB ) of ferrihydrite.…”

A Comprehensive Review on Graphitic Carbon Nitride for Carbon Dioxide Photoreduction

“…), changes the bandgap energy of the material and broadens its absorption capacity towards visible light region in the solar spectrum. [444][445][446][447][448][449] Figure 20 depicts the effect of several dopants on g-C 3 N 4 and the resulting reduction in bandgap energy compared to that of pure g-C 3 N 4 . Different experiments have been carried out to investigate the points of dopants (substitutional or interstitial) in the g-C 3 N 4 structural framework determined from the distance between host and guest lattices (inter-plane vs in-plane) and on the ionic radii of the dopants.…”