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Improving the Photocurrent in Quantum-Dot-Sensitized Solar Cells by Employing Alloy Pb_xCd_1-xS Quantum Dots as Photosensitizers.

ABSTRACT: Ternary alloy Pb_xCd_1-xS quantum dots (QDs) were explored as photosensitizers for quantum-dot-sensitized solar cells (QDSCs). Alloy Pb_xCd_1-xS QDs (Pb_0.54Cd_0.46S, Pb_0.31Cd_0.69S, and Pb_0.24Cd_0.76S) were found to substantially improve the photocurrent of the solar cells compared to the single CdS or PbS QDs. Moreover, it was found that the photocurrent increases and the photovoltage decreases when the ratio of Pb in Pb_xCd_1-xS is increased. Without surface protecting layer deposition, the highest short-circuit current density reaches 20 mA/cm² under simulated AM 1.5 illumination (100 mW/cm²). After an additional CdS coating layer was deposited onto the Pb_xCd_1-xS electrode, the photovoltaic performance further improved, with a photocurrent of 22.6 mA/cm² and an efficiency of 3.2%.

SUBMITTER: Yuan C

PROVIDER: S-EPMC5302620 | biostudies-literature | 2016 May

REPOSITORIES: biostudies-literature

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Improving the Photocurrent in Quantum-Dot-Sensitized Solar Cells by Employing Alloy PbxCd1-xS Quantum Dots as Photosensitizers.

Yuan Chunze C Li Lin L Huang Jing J Ning Zhijun Z Sun Licheng L Ågren Hans H

Nanomaterials (Basel, Switzerland) 20160525 6

Ternary alloy PbxCd1-xS quantum dots (QDs) were explored as photosensitizers for quantum-dot-sensitized solar cells (QDSCs). Alloy PbxCd1-xS QDs (Pb0.54Cd0.46S, Pb0.31Cd0.69S, and Pb0.24Cd0.76S) were found to substantially improve the photocurrent of the solar cells compared to the single CdS or PbS QDs. Moreover, it was found that the photocurrent increases a ...[more]

PMID: 28335226

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