Ta3N5 纳米管阵列用于可见光水光电解。

Ta3N5 nanotube arrays for visible light water photoelectrolysis.

机构信息

Materials Research Institute, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.

出版信息

Nano Lett. 2010 Mar 10;10(3):948-52. doi: 10.1021/nl903886e.

PMID:20146505

Abstract

Tantalum nitride (Ta3N5) has a band gap of approximately 2.07 eV, suitable for collecting more than 45% of the incident solar spectrum energy. We describe a simple method for scale fabrication of highly oriented Ta3N5 nanotube array films, by anodization of tantalum foil to achieve vertically oriented tantalum oxide nanotube arrays followed by a 700 degrees C ammonia anneal for sample crystallization and nitridation. The thin walled amorphous nanotube array structure enables transformation from tantalum oxide to Ta3N5 to occur at relatively low temperatures, while high-temperature annealing related structural aggregation that commonly occurs in particle films is avoided. In 1 M KOH solution, under AM 1.5 illumination with 0.5 V dc bias typical sample (nanotube length approximately 240 nm, wall thickness approximately 7 nm) visible light incident photon conversion efficiencies (IPCE) as high as 5.3% were obtained. The enhanced visible light activity in combination with the ordered one-dimensional nanoarchitecture makes Ta3N5 nanotube arrays films a promising candidate for visible light water photoelectrolysis.

摘要

氮化钽（Ta3N5）的能带隙约为 2.07eV，适合收集超过 45%的入射太阳光谱能量。我们描述了一种简单的方法来大规模制备高度取向的 Ta3N5 纳米管阵列薄膜，通过对钽箔进行阳极氧化以获得垂直取向的氧化钽纳米管阵列，然后在 700°C的氨气中退火以实现样品结晶和氮化。薄的无定形纳米管阵列结构使氧化钽向 Ta3N5 的转化能够在相对较低的温度下发生，同时避免了通常在颗粒膜中发生的高温退火相关结构聚集。在 1M KOH 溶液中，在 AM 1.5 光照下施加 0.5Vdc 偏压，典型样品（纳米管长度约为 240nm，壁厚约为 7nm）的可见光入射光子转换效率（IPCE）高达 5.3%。有序的一维纳米结构使 Ta3N5 纳米管阵列薄膜具有增强的可见光活性，成为可见光水光电解的有前途的候选材料。