A Selenium‐Substituted Low‐Bandgap Polymer with Versatile Photovoltaic Applications

A reduction of the bandgap and an enhancement of the charge transport properties of a LBG polymer (PBDTT-DPP) can be achieved simultaneously by changing the sulfur atoms on the DPP unit to selenium atoms. The newly designed polymer, PBDTT-SeDPP (Eg = 1.38 eV), shows excellent photovoltaic performance in single junction devices with power conversion efficiencies (PCEs) over 7% and photo-response up to 900 nm. A tandem polymer solar cell and a visibly transparent solar cell based on PBDTT-SeDPP show 9.5% and 4.5% PCEs, which are superior to those based on PBDTT-DPP. As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed and may be re-organized for online delivery, but are not copy-edited or typeset. Technical support issues arising from supporting information (other than missing files) should be addressed to the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.