Jump to main content
Jump to site search

Issue 25, 2017
Previous Article Next Article

Temperature-controlled evolution of microstructures that promote charge separation in a TaON photoanode for enhanced solar energy conversion

Author affiliations

Abstract

The microstructure of a semiconductor is strongly associated with the semiconductor liquid junction (SCLJ) electric field, which drives charge separation and transfer. Here, we have explored the water-saturated ammonia nitriding of a Ta2O5 precursor, a thermodynamically favorable reaction, to synthesize and tune the microstructure of a TaON material in a wide temperature range of 850–1050 °C. We found that, with increasing temperature, the microstructure evolved from porous particles with profiles of the parent precursor, to dispersed sintering particles with large sizes and smooth surfaces, due to grain growth. Furthermore, bulk charge separation and transfer was shown to be dependent on the temperature-controlled microstructure evolution. As a result, when coupled with a loading of Co(OH)x as a cocatalyst, the TaON particles grew at 1000 °C with high crystallinity, smooth surfaces and less grain boundaries, yielding a highest water splitting photocurrent of 2.3 mA cm−2 at 1.23 VRHE in 1 M NaOH under AM 1.5G simulated sunlight (100 mW cm−2). Therefore, we believe that owing to the temperature-sensitive microstructure evolution, water-saturated ammonia nitriding may be a potential avenue for synthesizing high-quality oxynitride photocatalysts for effectively separating and transporting charges.

Graphical abstract: Temperature-controlled evolution of microstructures that promote charge separation in a TaON photoanode for enhanced solar energy conversion

Back to tab navigation

Supplementary files

Publication details

The article was received on 28 Mar 2017, accepted on 22 May 2017 and first published on 23 May 2017


Article type: Paper
DOI: 10.1039/C7TA02704D
Citation: J. Mater. Chem. A, 2017,5, 12848-12855
  •   Request permissions

    Temperature-controlled evolution of microstructures that promote charge separation in a TaON photoanode for enhanced solar energy conversion

    L. Pei, Z. Xu, S. Yan and Z. Zou, J. Mater. Chem. A, 2017, 5, 12848
    DOI: 10.1039/C7TA02704D

Search articles by author

Spotlight

Advertisements