Photoelectrochemical Measurements of Thin Oxide Films: Multiple Internal Reflection Effects

Sukamto, J.P.H.; McMillan, Christopher S.; Kozlowski, Mark R.

doi:10.1149/1.2069336

Cited by 30 publications

(15 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As the r 0 values of the mixed oxide nanotubes are all smaller than 10 nm (retrieval length of TiO 2 50), holes are expected to escape recombination resulting in an enhanced photoconversion efficiency. 50,51 This is in agreement with van de Lagemaat and co-workers who observed a substantial enhancement of the quantum yield in porous SiC made by anodic etching in HF solutions. 51 Another factor could be that the NiO and MoO 3 help slow down charge recombination and/or facilitate the hole diffusion to the interface, which should improve the conversion efficiency.…”

Section: Optical and Photoelectrochemical Propertiessupporting

confidence: 90%

Ternary Ti–Mo–Ni mixed oxide nanotube arrays as photoanode materials for efficient solar hydrogen production

Allam

Deyab

Ghany

2013

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

To date, most studies on the fabrication and development of photoelectrodes for solar-fuel generation have been based on simple binary systems with limited success. However, ternary systems have not been explored extensively although they can offer more possibilities for band gap and band alignment tuning that allow the development of more efficient photoelectrochemical systems. Herein, we report on the growth of a novel ternary oxide photoanode material composed of self-ordered, vertically oriented nanotube arrays of titanium-molybdenum-nickel mixed oxide films via the anodization of a Ti-Mo-Ni alloy in an electrolyte solution of formamide containing NH4F at room temperature, followed by annealing in an air atmosphere. The nanostructure topology was found to depend on both the anodization time and the applied voltage. Our results demonstrate the ability to grow mixed oxide nanotube array films that are several microns thick. The Ti-Mo-Ni mixed oxide nanotube array films were utilized in solar-spectrum water photoelectrolysis, demonstrating a photocurrent density of 2.1 mA cm(-2) and a ∼10 fold increase in the photoconversion efficiency under AM 1.5 illumination (100 mW cm(-2), 1 M KOH) compared to pure TiO2 nanotubes fabricated under the same conditions. This enhancement in the photoconversion efficiency can be related to the synergistic effects of Ni and Mo alloying and the unique structural properties of the fabricated nanotube arrays.

show abstract

Section: Optical and Photoelectrochemical Propertiessupporting

confidence: 90%

Ternary Ti–Mo–Ni mixed oxide nanotube arrays as photoanode materials for efficient solar hydrogen production

Allam

Deyab

Ghany

2013

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

show abstract

“…In that paper a nonmonotonous dependence of the photocurrent intensity on the film thickness is also displayed. Such a phenomenon is caused by multiple internal reflections of the absorbed light at the metal/oxide/electrolyte interface, as formerly reported for anodic films on Nb [37,381 and Ti [39]. However, in the case of anodic Ti02 films, the change of crystallographic structure with increasing the film thickness (which implies a change of both the optical constants of the film and of the potential distribution inside the semiconducting oxide layer) hinders the possibility of simulating theoretically the experimental behaviour in a large thickness interval [39], at variance with the case of Nb205 anodic oxides [37, 381.…”

Section: Ef Ecsupporting

confidence: 59%

Influence of the crystallization process on the photoelectrochemical behaviour of anodic TiO₂ films

Piazza

Calá

Sunseri

et al. 1997

Ber Bunsenges Phys Chem

View full text Add to dashboard Cite

On the basis of kinetic and photoelectrochemical studies we show that the formation of amorphous or strongly disordered TiO, f i i s on electropolished titanium rods can occur upon anodization in 0.5 M H,SO, solution in a range of thickness which depends on the anodization rate. This finding is confirmed both by the changes in the shape of the photocurrent vs. potential curves with the energy of the incident photons, and by the impedance behaviour of the junction.Our data indicate that TiO, films having different degree of disorder are formed depending on the anodization rate and oxide thickness. Crystalline films are formed at very low growth rates since very low thicknesses. Amorphous or strongly disordered films can be grown at high oxidation rates ( 2 100 mV/s) before the onset of a crystallization process. At higher thicknesses a gradual crystallization process takes place, as revealed both by the decrease of the anodizing current during the tensiodynamic growth and by the changes in the shape of the photocurrent vs. potential curves. The onset of the crystallization process of the film occurs at higher thicknesses with increasing the growth rate.

show abstract

“…It was also reported that minority carriers generated within a distance from the surface equal to the sum of the depletion layer width and the diffusion length (retrieval length) escape recombination and reach the electrolyte 44 . Note that the relevant dimensional features of our TiON nanotube arrays (half the wall thickness) are all smaller than 10 nm, which is the range reported for crystalline TiO 2 retrieval length 45 . Therefore, bulk recombination is expected to be reduced and the photoconversion efficiency to be enhanced 46–48 .…”

Section: Resultsmentioning

confidence: 67%

Silver Nanoparticles-Decorated Titanium Oxynitride Nanotube Arrays for Enhanced Solar Fuel Generation

Soliman

Zedan

Khalifa

et al. 2017

Sci Rep

View full text Add to dashboard Cite

We demonstrate, for the first time, the synthesis of highly ordered titanium oxynitride nanotube arrays sensitized with Ag nanoparticles (Ag/TiON) as an attractive class of materials for visible-light-driven water splitting. The nanostructure topology of TiO2, TiON and Ag/TiON was investigated using FESEM and TEM. The X-ray photoelectron spectroscopy (XPS) and the energy dispersive X-ray spectroscopy (EDS) analyses confirm the formation of the oxynitride structure. Upon their use to split water photoelectrochemically under AM 1.5 G illumination (100 mW/cm2, 0.1 M KOH), the titanium oxynitride nanotube array films showed significant increase in the photocurrent (6 mA/cm2) compared to the TiO2 nanotubes counterpart (0.15 mA/cm2). Moreover, decorating the TiON nanotubes with Ag nanoparticles (13 ± 2 nm in size) resulted in exceptionally high photocurrent reaching 14 mA/cm2 at 1.0 VSCE. This enhancement in the photocurrent is related to the synergistic effects of Ag decoration, nitrogen doping, and the unique structural properties of the fabricated nanotube arrays.

show abstract

Photoelectrochemical Measurements of Thin Oxide Films: Multiple Internal Reflection Effects

Cited by 30 publications

References 33 publications

Ternary Ti–Mo–Ni mixed oxide nanotube arrays as photoanode materials for efficient solar hydrogen production

Ternary Ti–Mo–Ni mixed oxide nanotube arrays as photoanode materials for efficient solar hydrogen production

Influence of the crystallization process on the photoelectrochemical behaviour of anodic TiO₂ films

Silver Nanoparticles-Decorated Titanium Oxynitride Nanotube Arrays for Enhanced Solar Fuel Generation

Contact Info

Product

Resources

About

Photoelectrochemical Measurements of Thin Oxide Films: Multiple Internal Reflection Effects

Cited by 30 publications

References 33 publications

Ternary Ti–Mo–Ni mixed oxide nanotube arrays as photoanode materials for efficient solar hydrogen production

Ternary Ti–Mo–Ni mixed oxide nanotube arrays as photoanode materials for efficient solar hydrogen production

Influence of the crystallization process on the photoelectrochemical behaviour of anodic TiO2 films

Silver Nanoparticles-Decorated Titanium Oxynitride Nanotube Arrays for Enhanced Solar Fuel Generation

Contact Info

Product

Resources

About

Influence of the crystallization process on the photoelectrochemical behaviour of anodic TiO₂ films