3 years ago

Design and Fabrication of a Precious Metal-Free Tandem Core–Shell p+n Si/W-Doped BiVO4 Photoanode for Unassisted Water Splitting

Design and Fabrication of a Precious Metal-Free Tandem Core–Shell p+n Si/W-Doped BiVO4 Photoanode for Unassisted Water Splitting
Joshua M. McEnaney, Thomas F. Jaramillo, Pongkarn Chakthranont, Thomas R. Hellstern
Tandem photoelectrochemical water splitting cells utilizing crystalline Si and metal oxide photoabsorbers are promising for low-cost solar hydrogen production. This study presents a device design and a scalable fabrication scheme for a tandem heterostructure photoanode: p+n black silicon (Si)/SnO2 interface/W-doped bismuth vanadate (BiVO4)/cobalt phosphate (CoPi) catalyst. The black-Si not only provides a substantial photovoltage of 550 mV, but it also serves as a conductive scaffold to decrease charge transport pathlengths within the W-doped BiVO4 shell. When coupled with cobalt phosphide (CoP) nanoparticles as hydrogen evolution catalysts, the device demonstrates spontaneous water splitting without employing any precious metals, achieving an average solar-to-hydrogen efficiency of 0.45% over the course of an hour at pH 7. This fabrication scheme offers the modularity to optimize individual cell components, e.g., Si nanowire dimensions and metal oxide film thickness, involving steps that are compatible with fabricating monolithic devices. This design is general in nature and can be readily adapted to novel, higher performance semiconducting materials beyond BiVO4 as they become available, which will accelerate the process of device realization. A tandem heterojunction photoanode structure: p+n black-Si core/SnO2 interface/W-doped bismuth vanadate (BiVO4) shell/cobalt phosphate (CoPi) catalyst coupled with a cobalt phosphide (CoP) counter electrode demonstrates unassisted water splitting without the use of precious metal catalysts. The fabrication scheme offers wafer-scaled production and is applicable to other wide band gap semiconductors to enable the development of silicon (Si)-based tandem heterostrucure photoelectrodes.

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

DOI: 10.1002/aenm.201701515

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.