3 years ago

Role of Cl Ion Desorption in Photocurrent Enhancement of the Annealed Rutile Single-Crystalline TiO2 Nanorod Arrays

Role of Cl Ion Desorption in Photocurrent Enhancement of the Annealed Rutile Single-Crystalline TiO2 Nanorod Arrays
Rui-Qin Zhang, Juncao Bian, Chao Huang
TiO2 nanorods arrays (NRAs) have been considered as very promising photoanode materials in photoelectrochemical (PEC) cells. However, the performance of TiO2 NRAs still requires substantial improvement in order to reach the goal of practical applications. Annealing treatment of TiO2 NRAs can help to improve the PEC performance, but the mechanism is still not yet fully understood. In this work, we systematically investigated the optical and electronic properties, as well as the PEC performance of the thermally treated rutile single-crystalline TiO2 NRAs. Surprisingly, we recorded a maximum photocurrent density of 1.38 mA/cm2 at 1.3 V versus reversible hydrogen electrode for TiO2 NRAs annealed in O2, which is about 28 times higher than that of the pristine TiO2 NRAs. We further revealed that the surface adsorbed Cl ions largely suppress the photoresponse of the TiO2 NRAs as they serve as recombination centers and block the adsorption of water molecules to the surface of TiO2 NRAs. The enhancement in photocurrent after annealing in O2 is due to the desorption of the Cl ions, filling of the surface Vo, expansion of the depletion layer, and increase of the grain size. Our results shed light on the effect of annealing on the PEC performance of TiO2 NRAs and offer guidance for annealing of other semiconductor materials.

Publisher URL: http://dx.doi.org/10.1021/acs.jpcc.7b04071

DOI: 10.1021/acs.jpcc.7b04071

You might also like
Discover & Discuss Important Research

Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.