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arXiv · 1512.07466

A Silicon-Singlet Fission Parallel Tandem Solar Cell Exceeding 100 % External Quantum Efficiency

Luis M. Pazos·Ju Min Lee·Anton Kirch·Maxim Tabachnyk·Richard H. Friend·Bruno Ehrler
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Abstract

Silicon solar cells dominate the solar cell market with record lab efficiencies reaching almost 26%. However, after 60 years of research, this efficiency saturated close to the theoretical limit for silicon, and radically new approaches are needed to further improve the efficiency. Here we present parallel-connected tandem solar cells based on down-conversion via singlet fission. This design allows raising the theoretical power conversion efficiency limit to 45% with far superior stability under changing sunlight conditions in comparison to traditional series tandems. We experimentally demonstrate a silicon/pentacene parallel tandem solar cell that exceeds 100% external quantum efficiency at the main absorption peak of pentacene, showing efficient photocurrent addition and proving this design as a realistic prospect for real-world applications.

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Luis M. Pazos, Ju Min Lee, Anton Kirch, Maxim Tabachnyk, Richard H. Friend, Bruno Ehrler. 2015-12-23. A Silicon-Singlet Fission Parallel Tandem Solar Cell Exceeding 100 % External Quantum Efficiency. https://doi.org/10.1021/acsenergylett.6b00678

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