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Photovoltage Reversal in Organic Optoelectronic Devices with Insulator-Semiconductor Interfaces.

ABSTRACT: Photoinduced space-charges in organic optoelectronic devices, which are usually caused by poor mobility and charge injection imbalance, always limit the device performance. Here we demonstrate that photoinduced space-charge layers, accumulated at organic semiconductor-insulator interfaces, can also play a role for photocurrent generation. Photocurrent transients from organic devices, with insulator-semiconductor interfaces, were systematically studied by using the double-layer model with an equivalent circuit. Results indicated that the electric fields in photoinduced space-charge layers can be utilized for charge generation and can even induce a photovoltage reversal. Such an operational process of light harvesting would be promising for photoelectric conversion in organic devices.

SUBMITTER: Hu L

PROVIDER: S-EPMC6163970 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Photovoltage Reversal in Organic Optoelectronic Devices with Insulator-Semiconductor Interfaces.

Hu Laigui L Jin Wei W Feng Rui R Zaheer Muhammad M Nie Qingmiao Q Chen Guoping G Qiu Zhi-Jun ZJ Cong Chunxiao C Liu Ran R

Materials (Basel, Switzerland) 20180825 9

Photoinduced space-charges in organic optoelectronic devices, which are usually caused by poor mobility and charge injection imbalance, always limit the device performance. Here we demonstrate that photoinduced space-charge layers, accumulated at organic semiconductor-insulator interfaces, can also play a role for photocurrent generation. Photocurrent transients from organic devices, with insulator-semiconductor interfaces, were systematically studied by using the double-layer model with an equi ...[more]

PMID: 30149604

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