用于太阳能高效光电化学转换的层状氮氧化钽纳米棒阵列毯：实验与密度泛函理论见解

Layered tantalum oxynitride nanorod array carpets for efficient photoelectrochemical conversion of solar energy: experimental and DFT insights.

作者信息

Allam Nageh K, Shaheen Basamat S, Hafez Ahmed M

机构信息

Energy Materials Laboratory (EML), Physics Department, School of Sciences and Engineering, The American University in Cairo , New Cairo 11835, Egypt.

出版信息

ACS Appl Mater Interfaces. 2014 Apr 9;6(7):4609-15. doi: 10.1021/am500286n. Epub 2014 Mar 28.

DOI:10.1021/am500286n

PMID:24666372

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.

摘要

通过在氨气氛中进行氮化处理，将阳极制备的氧化钽（Ta2O5）纳米棒阵列地毯转化为相应的氮氧化钽（TaON）。测得的TaON光学带隙能量约为2.3 eV，这也通过密度泛函理论计算得到了证实。当用于光电化学分解水（AM 1.5G光照、1 M KOH和0.6 V施加直流偏压）时，多层纳米棒薄膜显示出高达7.5%的可见光入射光子转换效率（IPCE）。从有序的一维形态以及TaON和Ta2O5中的电子有效质量方面讨论了增强的光化学活性。