{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,12]],"date-time":"2026-05-12T02:19:41Z","timestamp":1778552381468,"version":"3.51.4"},"reference-count":32,"publisher":"AIP Publishing","issue":"15","funder":[{"name":"Excellence Cluster Nanosystems Initiative Munich"},{"name":"TUM.solar in the frame of the Bavarian Collaborative Research Project"}],"content-domain":{"domain":["pubs.aip.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2015,10,21]]},"abstract":"<jats:p>In this work, we use GaN with different deposited Pt nanostructures as a controllable model system to investigate the kinetics of photo-generated charge carriers in hybrid photocatalysts. We combine conductance and contact potential difference measurements to investigate the influence of Pt on the processes involved in the capture and decay of photo-generated charge carriers at and close to the GaN surface. We found that in the presence of Pt nanostructures the photo-excitation processes are similar to those found in Pt free GaN. However, in GaN with Pt nanostructures, photo-generated holes are preferentially trapped in surface states of the GaN covered with Pt and\/or in electronic states of the Pt and lead to an accumulation of positive charge there, whereas negative charge is accumulated in localized states in a shallow defect band of the GaN covered with Pt. This preferential accumulation of photo-generated electrons close to the surface is responsible for a dramatic acceleration of the turn-off charge transfer kinetics and a stronger dependence of the surface photovoltage on light intensity when compared to a Pt free GaN surface. Our study shows that in hybrid photocatalysts, the metal nanostructures induce a spatially inhomogeneous surface band bending of the semiconductor that promotes a lateral drift of photogenerated charges towards the catalytic nanostructures.<\/jats:p>","DOI":"10.1063\/1.4933175","type":"journal-article","created":{"date-parts":[[2015,10,22]],"date-time":"2015-10-22T07:58:06Z","timestamp":1445500686000},"update-policy":"https:\/\/doi.org\/10.1063\/aip-crossmark-policy-page","source":"Crossref","is-referenced-by-count":7,"title":["Kinetics of optically excited charge carriers at the GaN surface: Influence of catalytic Pt nanostructures"],"prefix":"10.1063","volume":"118","author":[{"given":"Andrea","family":"Winnerl","sequence":"first","affiliation":[{"name":"Technische Universit\u00e4t M\u00fcnchen Walter Schottky Institut and Physik Department, , Am Coulombwall 4, 85748 Garching, Germany"}]},{"given":"Rui N.","family":"Pereira","sequence":"additional","affiliation":[{"name":"Technische Universit\u00e4t M\u00fcnchen Walter Schottky Institut and Physik Department, , Am Coulombwall 4, 85748 Garching, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0068-3505","authenticated-orcid":false,"given":"Martin","family":"Stutzmann","sequence":"additional","affiliation":[{"name":"Technische Universit\u00e4t M\u00fcnchen Walter Schottky Institut and Physik Department, , Am Coulombwall 4, 85748 Garching, Germany"}]}],"member":"317","published-online":{"date-parts":[[2015,10,21]]},"reference":[{"key":"2023062400421351300_c1","doi-asserted-by":"publisher","first-page":"51","DOI":"10.1126\/science.267.5194.51","article-title":"High-luminosity blue and blue-green gallium nitride leds","volume":"267","year":"1995","journal-title":"Science"},{"key":"2023062400421351300_c2","doi-asserted-by":"publisher","first-page":"2131","DOI":"10.1016\/S0038-1101(98)00208-1","article-title":"GaN based transistors for high power applications","volume":"42","year":"1998","journal-title":"Solid State Electron."},{"key":"2023062400421351300_c3","doi-asserted-by":"publisher","first-page":"2154","DOI":"10.1063\/1.119366","article-title":"High speed, low noise ultraviolet photodetectors based on GaN p-i-n and AlGaN(p)-GaN(i)-GaN(n) structures","volume":"71","year":"1997","journal-title":"Appl. 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