Study on the photoelectrical performance of anodized titanium sheets.

Xiangping Chen,Lishi Wang,Xin Li,Dedong Chen

doi:10.1098/rsos.201778

Abstract

Anodization is a widely used method to obtain multicoloured oxidized titanium sheets. However, most researchers paid great attention to the colour-related properties instead of photoelectrical properties of titanium oxide film obtained by anodization. In this work, to study their photoelectrical properties, a series of multicoloured oxidized titanium sheets were prepared by anodization method, and UV–vis absorption and photocurrents were tested. The relationship between anodization voltages/anodization durations and photocurrents of titanium sheets was studied. Results show that titanium sheets have excellent photoelectrical performance. With the increase of anodization voltage, the number of UV–vis absorption peaks increased under visible light which means increasing absorption. When anodization duration increased, absorption band edge also increased in the visible light region, which means the band gap needed to produce charge transfer transition decreased. Under simulated sunlight and applied voltage of +0.4 V, photocurrent increased with the increase of either anodization voltage or anodization duration, and can be expressed by linear equations. In addition, anodization currents were recorded during anodization. Morphology, crystal structure and photoelectrical properties of anodized titanium sheets were characterized. The anodized titanium sheets can not only be used as decorative material in jewellery and architecture fields etc. but also are supposed to be used as photoelectrical catalyst in further work.

Highlights

Titanium has high corrosion resistance and chemical stability, and is frequently used in implanting field [1,2] and aeronautics [3,4]
Anodization duration was kept at 10 min, and anodization voltages were 20, 25, 40, 60, 80, 90, 100, 120 and 140 V, respectively, and photocurrents of those anodized titanium sheets were tested and converted into photocurrent density in figure 6a(a–i)
Anodization voltage was kept at 100 V, and anodization durations were 10, 30, 60, 180 and 300 min, respectively, and photocurrents of those anodized titanium sheets were tested and converted into photocurrent density in figure 7a(a–e)

Summary

Introduction

Titanium has high corrosion resistance and chemical stability, and is frequently used in implanting field [1,2] and aeronautics [3,4]. 2 Since Japanese scientists Fujishima and Honda first used semiconductor TiO2 to decompose water into hydrogen and oxygen in 1972 [15], the photocatalytic material technology using semiconductor as photocatalyst has become one of hot research directions in the field of clean energy. Great effort has been devoted by researchers around the world to the photoelectric catalysis of semiconductor TiO2 under simulated sunlight, which is widely used in photocatalyst, sensors, biomedicine and other fields [16,17,18,19,20,21,22,23,24,25,26]. The main challenge is still the low photoelectrical conversion efficiency and stability of photocatalytic materials [27,28,29]

Methods

Results

Conclusion