Ultrafast carrier dynamics in BiVO4: Interplay between free carriers, trapped carriers and low-frequency lattice vibrations

Benjamin J. Dringoli, Keith T. Butler, Lite Zhou, Binod Giri, Pratap M. Rao, A. Walsh, Lyubov V. Titova

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

BiVO4 is a promising material for solar energy conversion applications. However, it suffers from low mobility due to strong carrier-phonon coupling, which favors formation of polarons. To elucidate carrier transport mechanisms in BiVO4, we apply time-resolved THz spectroscopy to probe dynamics of photexcited carriers and their coupling to lattice vibrational modes at early times (1-20 ps) after photoexcitation. We find that at high excitation fluences, trap states are saturated and a short-lived population of highly mobile residual carriers exists. At the same time, saturation of hole trap states manifests itself in changes in the low-frequency (1.92 THz) seesaw phonon mode between the Bi and VO4 units.

Original languageEnglish
Title of host publication41st International Conference on Infrared, Millimeter and Terahertz Waves, IRMMW-THz 2016
PublisherIEEE Computer Society
Volume2016-November
ISBN (Electronic)9781467384858
DOIs
Publication statusPublished - 2016 Nov 28
Event41st International Conference on Infrared, Millimeter and Terahertz Waves, IRMMW-THz 2016 - Copenhagen, Denmark
Duration: 2016 Sep 252016 Sep 30

Other

Other41st International Conference on Infrared, Millimeter and Terahertz Waves, IRMMW-THz 2016
CountryDenmark
CityCopenhagen
Period16/9/2516/9/30

    Fingerprint

All Science Journal Classification (ASJC) codes

  • Energy Engineering and Power Technology
  • Electrical and Electronic Engineering

Cite this

Dringoli, B. J., Butler, K. T., Zhou, L., Giri, B., Rao, P. M., Walsh, A., & Titova, L. V. (2016). Ultrafast carrier dynamics in BiVO4: Interplay between free carriers, trapped carriers and low-frequency lattice vibrations. In 41st International Conference on Infrared, Millimeter and Terahertz Waves, IRMMW-THz 2016 (Vol. 2016-November). [7758784] IEEE Computer Society. https://doi.org/10.1109/IRMMW-THz.2016.7758784