English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Tools annual

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

The dynamics of photogenerated holes in undoped BiVO\ud4\udphotoanodes for water splitting were studied\udusing  transient  absorption  spectroscopy,  correlated  with  photoelectrochemical  and  transient\udphotocurrent data. Transient absorption signals of photogenerated holes were identi\udfi\uded using electron/\udhole scavengers and applied electrical bias in a complete photoelectrochemical cell. The yield of long-\udlived (0.1\ud–\ud1 s) photogenerated holes is observed to correlate as a function of applied electrical bias with\udthe width of the space charge layer, as determined by electrochemical impedance spectroscopy. The\udtransient absorption decay time constant of these long-lived holes is also observed to be dependent\udupon the applied bias, assigned to kinetic competition between water oxidation and recombination of\udthese surface accumulated holes with bulk electrons across the space charge layer. The time constant\udfor this slow recombination measured with transient absorption spectroscopy is shown to match the\udtime constant of back electron transfer from the external circuit determined from chopped light\udtransient photocurrent measurements, thus providing strong evidence for these assignments. The yield\udof water oxidation determined from these measurements, including consideration of both the yield of\udlong-lived holes, and the fraction of these holes which are lost due to back electron/hole recombination,\udis observed to be in good agreement with the photocurrent density measured for BiVO\ud4\udphotoanodes as\uda function of bias under continuous irradiation. Overall these results indicate two distinct recombination\udprocesses which limit photocurrent generation in BiVO\ud4\udphotoanodes:\udfi\udrstly rapid (\ud#\udmicroseconds)\udelectron/hole recombination, and secondly recombination of surface-accumulated holes with bulk\udBiVO\ud4\udelectrons. This second\ud‘\udback electron transfer\ud’\udrecombination occurs on the milliseconds\ud–\udseconds timescale, and is only avoided at strong anodic biases where the potential drop across the\udspace charge layer provides a su\udffi\udciently large energetic barrier to prevent this recombination process

Dynamics of photogenerated holes in undoped BiVO4 photoanodes for solar water oxidation

Dynamics of photogenerated holes in undoped BiVO₄ photoanodes for solar water oxidation