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Photoconductivity of PbS/perovskite quantum dots in gold nanogaps.

ABSTRACT: We demonstrate that the photoconductance of colloidal PbS/MAPbI₃ quantum dots in nanoscale gold electrode gaps shows a consistent power law dependence of the photocurrent on the light intensity with an exponent slightly below 0.7. The gap sizes are between 25 and 800 nm and by scanning photocurrent microscopy we evidence the strong localization and high reproducibility of photocurrent generation. We probe different flat-faced and pointed electrodes for excitation light in the red and near infrared spectral range and laser irradiances from 10^-2 to 10² W cm^-2. Our material combination provides practically identical photocurrent response for a wide range of gap sizes and geometries, highlighting its generic potential for nanoscale light coupling and detection.

SUBMITTER: Grimaldi D

PROVIDER: S-EPMC9400517 | biostudies-literature | 2022 Aug

REPOSITORIES: biostudies-literature

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Photoconductivity of PbS/perovskite quantum dots in gold nanogaps.

Grimaldi Dario D Kelderer Emil E Dirin Dmitry N DN Kovalenko Maksym V MV Hohenau Andreas A Ditlbacher Harald H Krenn Joachim R JR

Nanoscale advances 20220718 17

We demonstrate that the photoconductance of colloidal PbS/MAPbI<sub>3</sub> quantum dots in nanoscale gold electrode gaps shows a consistent power law dependence of the photocurrent on the light intensity with an exponent slightly below 0.7. The gap sizes are between 25 and 800 nm and by scanning photocurrent microscopy we evidence the strong localization and high reproducibility of photocurrent generation. We probe different flat-faced and pointed electrodes for excitation light in the red and ...[more]

PMID: 36134347

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