5 years ago

Enhanced Solar Water Splitting by Swift Charge Separation in Au/FeOOH Sandwiched Single-Crystalline Fe2O3 Nanoflake Photoelectrodes

Enhanced Solar Water Splitting by Swift Charge Separation in Au/FeOOH Sandwiched Single-Crystalline Fe2O3 Nanoflake Photoelectrodes
Yingpu Bi, Lei Wang, Yajun Zhang, Nhat Truong Nguyen, Patrik Schmuki
In this work, single crystalline α-Fe2O3 nanoflakes (NFs) are formed in a highly dense array by Au seeding of a Fe substrate by a thermal oxidation technique. The NFs are conformally decorated with a thin FeOOH cocatalyst layer. Photoelectrochemical (PEC) measurements show that this photoanode, incorporating α-Fe2O3/FeOOH NFs rooted on the Au/Fe structure, exhibits significantly enhanced PEC water oxidation performance compared to the plain α-Fe2O3 nanostructure on the Fe substrate. The α-Fe2O3/FeOOH NFs on Au/Fe photoanode yields a photocurrent density of 3.1 mA cm−2 at 1.5 VRHE, and a remarkably low onset potential of 0.5–0.6 VRHE in 1 m KOH under AM 1.5G (100 mW cm−2) simulated sunlight illumination. The enhancement in PEC performance can be attributed to a synergistic effect of the FeOOH top decoration and the Au underlayer, whereby FeOOH facilitates hole transfer at the interface of electrode/electrolyte and the Au layer provides a sink for the electron transport to the back contact. This results in a drastically improved charge-separation efficiency in the single crystalline α-Fe2O3 NF photoanode. Flake news: FeOOH and Au layers on single-crystalline α-Fe2O3 nanoflake photoanodes display a synergistic effect in water splitting. Au seeding provides nucleation centers to grow high-density hematite nanoflake arrays on Fe substrate. Additional FeOOH decoration facilitates hole transfer at the electrode/electrolyte interface, while the remaining Au underlayer provides a sink for electron transport to the back contact, leading to drastically improved charge-separation efficiency.

Publisher URL: http://onlinelibrary.wiley.com/resolve/doi

DOI: 10.1002/cssc.201700522

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.