title: Layered tantalum oxynitride nanorod array carpets for efficient photoelectrochemical conversion of solar energy: experimental and DFT insights.
abstract: Anodically fabricated tantalum oxide (Ta2O5) nanorod array carpets are converted into the corresponding tantalum oxynitride (TaON) through nitridation in an ammonia atmosphere. The measured optical bandgap energy of TaON is ∼2.3 eV, which is also confirmed via the density functional theory calculations. When used to photoelectrochemically split water (AM 1.5G illumination, 1 M KOH, and 0.6 V applied DC bias), the multilayer nanorod films show visible-light incident photon conversion efficiencies (IPCE) as high as 7.5%. The enhanced photochemical activity is discussed in terms of the ordered one-dimensional morphology as well as the electron effective mass in TaON and Ta2O5.
authors.affiliation: Energy Materials Laboratory (EML), Physics Department, School of Sciences and Engineering, The American University in Cairo , New Cairo 11835, Egypt.
authors.forename: Nageh K
authors.initials: NK
authors.lastname: Allam
authors.forename: Basamat S
authors.initials: BS
authors.lastname: Shaheen
authors.forename: Ahmed M
authors.initials: AM
authors.lastname: Hafez