Nageh Allam - Vertically Oriented Ti–Pd Mixed Oxynitride Nanotube Arrays for Enhanced Photoelectrochemical Water Splitting

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      Publication Details (including relevant citation   information):

      ACS Nano, 2011,   5 (6), pp 5056–5066

      DOI: 10.1021/nn201136t

      Abstract:

      In recent years, considerable efforts have been made to design   and discover photoactive nanostructured materials that can be   used as anodes in water photoelectrolysis cells. Herein, we   report on the growth of a novel photoanode material composed of   self-ordered, vertically oriented nanotube arrays of   titanium–palladium mixed oxynitride films via  anodization of Ti–Pd alloy in an electrolyte solution of   formamide containing NH4F at room temperature,   followed by annealing in an ammonia 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 oxynitride nanotube array films that are several   micrometers thick. The Ti–Pd oxynitride nanotube array films were   utilized in solar-spectrum water photoelectrolysis, demonstrating   a photocurrent density of 1.9 mA/cm2 and a 5-fold   increase in the photoconversion efficiency under AM 1.5   illumination (100 mW/cm2, 1.0 M KOH) compared to pure   TiO2 nanotubes fabricated and tested under the same   conditions. The obtained efficiency is among the highest reported   values for a TiO2 nanotube-based photoelectrochemical   cell. This enhancement in the photoconversion efficiency is   related to the synergistic effects of Pd alloying, nitrogen   doping, and the unique structural properties of the fabricated   nanotube arrays.

      Address (URL): http://pubs.acs.org/doi/abs/10.1021/nn201136t?prevSearch=%255BAllField%253A%2B%2 55BAllField%253A%2BNageh%2BAllam%255D%255D&searchHistoryKey=